Les lasers à fibre suscitent un grand intérêt dans tous les domaines, pour des applications allant du médical aux télécommunications, car ils permettent d'obtenir une bonne cohérence spatiale et temporelle et sont compacts et robustes. La limite se situe dans le domaine des lasers à fortes puissances. La combinaison de plusieurs sources lasers est alors une solution prometteuse pour surpasser les limites individuelles de ces sources, en particulier les techniques de combinaisons cohérentes de faisceaux. Dans cette famille de combinaison, la technique de contrôle actif de la phase par marquage en fréquence est particulièrement intéressante, mais deux limitations majeures ont été identifiées : le cas du régime impulsionnel ainsi que le nombre limité de voies pouvant être mise en phase. Dans cette thèse des solutions sont proposées pour lever ces limitations. Dans un premier temps, nous avons réalisé la première démonstration expérimentale d'une combinaison cohérente impulsionnelle utilisant cette technique. Ensuite, en adaptant des techniques de codage orthogonal issues du domaine des télécommunications, nous avons augmenté le nombre de voies pouvant être combinées. Un outil de simulation du système a été développé pour étudier l'utilisation des techniques de codage et pour étudier la propagation des faisceaux à travers la turbulence atmosphérique. Pour évaluer les performances des systèmes à grand nombre d'émetteur, nous avons mis en place une méthodologie, basée sur l'utilisation de plans d'expériences et de métamodèles, permettant d'identifier les fibres ou les interactions entre fibres les plus influentes, en fonction des paramètres initiaux de la combinaison. / A great interest exists for fibre lasers in all domains, from medical to telecommunication applications, as they enable to achieve a good spatial and spectral coherence and they are compact and robust. The limit comes from high-power applications. The combination of several laser sources is therefore a solution to overcome the limitations of individual emitter, especially coherent combining techniques. In this combination form, the active phase control by frequency tagging technique looks the most promising one, but two main limitations were identified : the pulse regime and the limited number of channels, which can be phase-locked. In this thesis, solutions are proposed to overcome these limitations. At first, we realised the first experimental demonstration of a pulse coherent combination using this technique. Then by adapting orthogonal coding tehniques from the telecommunication domain, we increased the number of channels which can be combined. A simulation tool was developped to study the coding techniques as well as the propagation of the beams through a turbulent atmosphere. To evaluate the performances of systems with a large number of emitters, we developped a methodology based on the use of numerical designs of experiments and metaodels, enabling us to identify the most influent fibres or interactions between fibres, as a function of the initial parameters of the combination.

This study attempts to ‘re-member' the post-slave South African female body through personal performance practice. It addresses re-membering both as an embodied activity of Recalling erased memory and as a recuperation of the dis-membered post-slave female body. Through reflecting on two examples of personal performance practice, What the Water Gave Me (2000) and Spice Root (2005), I use my own post-slave body as the locus of Intersection between the private and the political, the biological and the historical. The transmission of cultural memory through performance is traced through Joseph Roach's (1996) ‘surrogation' and Diana Taylor's (2003) ‘Repertoire'. Specifically, I employ a syncretic spirituality and objects of cultural memory to re-member a diasporic narrative continuity and recuperate embodied feminine agency. Gabeba Baderoon's (2014) perspective on the Indian Ocean as site of colonial slavery and cultural memory across diaspora and Raissa De Smet Trumbull's (2010) monograph on ‘Oceanic liquidity' inspire a figuration of the Ocean as an embodied, affective, anti-colonial presence. These modalities also inflect the style of writing in my inquiry, thus privileging the material/maternal, cyclical, leaky and excessive qualities of water a counter-hegemonic practice.

THE EFFECTS OF ENVIRONMENTAL TEMPERATURE ON LOCOMOTOR PERFORMANCE AND GROWTH PATTERNS IN SPOTTED SALAMANDER, AMBYSTOMA MACULATUM SEPTEMBER 2010 SUELLEN ALMEIDA, B.A., UNIVERSITY OF MASSACHUSETTS AMEHRST M.A., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Duncan J. Irschick Variation in temperature has a profound effect on many aspects of an animal’s physiology, behavior, and performance capacities. Although animals are capable of coping with a range of temperature, they are adapted to specific boundaries of temperature. In an era of global climate change, it is fundamental to comprehend how organisms will react in relation to temperature-related stress and how warmer environmental temperature will affect whole organism performance, as these traits are often crucial to survival. In this study, I examined the effects of temperature on time to hatching period, body length, and larval growth rate. Specifically, I address the following two questions. First, does an increase in temperature affect the duration of time to hatching period? Second, do temperature and the duration of the time to hatching period affect body length at the time of hatching, subsequent growth rate? Furthermore, I investigate the effects of temperature on larval locomotor performance by examining whether or not temperature can result in any impairment of locomotor performance variables (velocity and acceleration). Specifically, I wish to address the following question, does an increase in environmental temperature affect both larval maximum and average velocity and acceleration? In order to answer such questions I raised one egg cluster of Spotted Salamander, Ambystoma maculatum, in two different temperatures (15°C and 21°C). I maintained both the eggs and the resulting larvae in these different temperature regimes until the larvae had reached two weeks of age. I then examined the effects of temperature on body length, growth rate, and locomotor performance. I found that temperature does not have a direct significant effect on body length in A. maculatum. However, I found that temperature has a significant effect on the length of time to hatching period and that the length of time to hatching period is directly correlated to body length. I also found that temperature does not have a significant effect on larval velocity but does have a significant effect on larval acceleration. I argue here that an increase in the mean environmental temperature could result in a decrease in locomotor performance and consequent higher predation susceptibility.

This study utilized Relational Dialectics Theory 2.0 to examine how adult adoptees constructed the meaning of the term parent following contact with a birth parent. Semi-structured interviews were conducted with 30 adult adoptees who had made contact with a birth parent. Two primary discourses emerged. The discourse of parent as a specific person (DPSP) emerged when participants felt that parent referred exclusively to their adoptive parents; the definition did not change when participants made contact with their birth parent. The discourse of parent as a label (DPL) emerged when participants defined parent as a flexible role that could be filled by multiple people; their definition of parent changed only after making contact with their birth parent, and they included their birth parent in their definition of parent. These discourses demonstrated interplay through negating, countering, and entertaining. The results of this study add to the literature on adoptive family communication and Relational Dialectics Theory.

Includes bibliographical references (leaves 66-69). / This paper explores the convergence and cusp of colliding realities in private and public identities in performative contexts. It draws heavily on a Socio-Anthropological system of the self and fictive personas within these constructs - as well as the perscnlpersonalpersonality trichotomy inherent in self~presentation and preservation. It is written in subservience and supplication to the practical component of the University of Cape Town's MA in Theatre and Performance (Theatre Making) which is also documented and archived with supplementary photographs as part of the research. The paper addresses notions of collective identity (such as gender, sexuality, race, ethnicity, socio-economic and socio-political group clusters) with a peripheral focus on the South African, middle-class, Caucasian identity and a particular focus on a female, hetero-normative orientation (as it forms the premise of many concerns presented in the practice of the inquiry: the artist as still iife, the subject as object). It suggests a methodology towards aligning the research and its actualisation in performance through a series of installation-based works presented on and around Hiddingh Campus, Cape Town between May 2008 and September 2009. At the time of publication, the culminating project of the degree was in its pre-production phase.

High performance demands made to employees by supervisors can be perceived as motivating or abusive depending on the "eye of the beholder" (Bies et al., 2016). One of the ways in which supervisors make high performance demands is by putting pressure on their employees to successfully complete their job tasks. However, the extant literature is inconsistent in terms of the outcomes of experiencing general performance pressure. Some studies show that it leads to functional outcomes (e.g., Eisenberger & Aselage, 2009), while others show that it leads to dysfunctional ones (e.g., Mitchell et al., 2018). Recent work integrates these findings, explaining that performance pressure is a dynamic phenomenon, fluctuating within-person on a daily level, leading to both positive outcomes as well as negative ones (Mitchell et al., 2019). Drawing on the Job Demands and Resources Model (Demerouti et al., 2001), supplemented by Basic Psychological Needs Theory (Deci & Ryan, 2000), I conduct an empirical study with an experience sampling methodology to assess the daily, within-person process of interpreting performance pressure from the supervisor and the impact of the process on individual wellbeing and workplace deviance behavior. I also investigate how recovery pressure from the supervisor interacts with daily performance pressure to play a moderating role. I discuss theoretical contributions and practical implications.

One's immediate supervisor is an important source of appreciation and recognition. Although employees expect and desire high levels of appreciation from supervisors, they report feeling less appreciated at work than in any other domain of life (cf. Kaplan, 2012; Luthans, 2000). At the same time, supervisors report that they express appreciation to subordinates very frequently (Kaplan, 2012; Luthans, 2000). Given this disconnect, the purpose of my dissertation is to examine the relationship between supervisors' expressed appreciation and subordinates' felt appreciation. To do so, I present three papers that explore appreciation as a relational phenomenon. In Chapter 1, I review the appreciation literature and propose the construct of appreciation (dis)agreement. In Chapter 2, I investigate antecedents and outcomes of (dis)agreement in the supervisor-subordinate relationship. Results from a time-lagged survey study of 157 supervisor-subordinate dyads indicate substantial disagreement between supervisors and subordinates regarding appreciation. Moreover, LMS analyses suggest that agreement on high appreciation, relative to low appreciation, is positively related to relational outcomes such as relationship satisfaction, positive relational tone, and relational maintenance behaviors. Finally, in Chapter 3, drawing on communicative responsibility theory I suggest a supervisor and a subordinate awareness intervention to address the disconnect between supervisors' expressions of appreciation and subordinates' feelings of appreciation. Results of this intervention study, in a sample of 161 supervisor-subordinate dyads, reveal support for the interventions' effects. Implications and future directions are discussed.

Queers of colour are in real and constant danger as they are not seen to belong neatly to either Western queer culture (due to their blackness) or African culture (due to their queerness). This discursive violence legitimizes actual violence on black queer bodies. This research project uses performance as a tool to address black queer erasure and aims to debunk the tired claim that queerness is un-African. In my final thesis production and its accompanying explication, I engage with memory and practices of queer self-fashioning as a means of contesting oppressive, hegemonic, and heteronormative ideologies of gendered racial belonging. Memory thus serves as both a critical concept and an aesthetic impulse in my practice of queer space making. I use performances of intimate childhood memories of shame and othering to articulate how black queer subjects emerge in distinct relation and/or contra-position to the white Euro-American identity construct that dominates understanding of queer citizenship and politics. In so doing, I work towards naming and enacting a “quare” (Johnson, 2001, p. 8) politics that attends to the specificity of black queer lifeworlds. Producing a counterhegemonic queer space that is attentive to the potentially generative tensions between “queerness” and black African indigenous ontologies enables the envisioning and affirming of black African queer subjectivity in all its complexity. I use Johnson's critical reframing of ‘queer' as ‘quare' as the basis for my engagement with queerof-colour critiques of hetero- and homonormativity. Quare in this research study is deployed as part of various contemporary endeavours to locate racialised and class knowledge in identity. It is also used to articulate genderqueer and sexually non-conforming subjectivities such that ways of knowing are viewed both as “discursively mediated and as historically situated and materially conditioned” (Johnson, 2001, p. 13). The practice of self-reflexivity through performance is posited as a method for self-image fashioning in this study. Further, I show in my performance work that Johnson's (2001) construal of self-image-making and performativity have potential for restoring subjectivity and agency through the performance of self.

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