追蹤股係資產重組方式的一種，近年來在美國的證券市場增加許多的發行案例，追蹤股是針對多角化企業特定部門發行不同權利義務的普通股，表彰該特定企業的營運績效，提供給投資人更明確的投資評價，進而提升企業整體的價值。追蹤股的起源係於1984年General Motors在取得Ross Perot’s Electronic Data System後發行首創的追蹤股，雖然陸續有發行之個案，但追蹤股的發行熱潮主要集中於1998年至2000年，包括AT&T、Sprint Corp、Quantum Corp.及Disney等企業，且部分發行企業發行一種以上的追蹤股，因追蹤股可依發行企業的需求制定不同的投票權、轉換權、股利分配政策等，提供給投資者相當多的選擇，顯示追蹤股對企業的籌資或購併提供了新的工具。 由於追蹤股的發行案例較其他資產重組的方式(資產分拆及權益分割)相對較少，因此國外探討此專題的文獻亦不多見，國內目前亦無相關研究。故本研究的主要內容包括資產重組方式的分析及可能的考量因素，並說明追蹤股的起源、特性及優缺點，進而探討追蹤股發行時的宣告效果，觀察其累計異常報酬的顯著性，且驗證累計異常報酬與發行企業市值及市價淨值比的關係。 為提供國內研究者更清楚的了解追蹤股發行全貌，本研究將1998年在美國證券市場發行的Sprint Corp的個案，針對發行的目的、發行架構、該普通股的權利義務及可能的風險等項目加以分析研究。最後以模擬國內上市公司—中華電信發行追蹤股的可行性，提供國內主管機關作為未來研究新金融商品的建議及參考。

<p>The work in this thesis deals with the ecology and evolution of adaptive individual variation. Ecologists have long used niche theory to describe the ecology of a species as a whole, treating conspecific individuals as ecological equivalent. During recent years, research about individual variation in diet and morphology has gained interest in adaptive radiations and ecological speciation. Such variation among individual niche use may have important conservation implications as well as ecological and evolutionary implications. However, up to date we know very little about the extension of this phenomenon in natural populations and the mechanisms behind it.</p><p>The results in this thesis show that the extension of individual diet specialization is widely spread throughout the animal kingdom. The variation in diet is mainly correlated to morphological variation but not always. Furthermore, this variation in diet and morphology among individuals could be both genetically determined and environmentally induced and it mainly comes from trade-offs in foraging efficiency between different prey types. </p><p>The results from a number of studies of perch also show that individual perch differ in morphology and diet depending on habitat, where littoral perch has a deeper body compared to pelagic perch. This difference in morphology corresponds to functional expectations and is related to foraging efficiency trade-offs between foraging in the littoral and pelagic zone of a lake. The variation in morphology in perch is mainly due to phenotypic plasticity but there are also small genetic differences between the littoral and pelagic perch. Two separate studies show that both predation and competition may be important mechanism for the variation in morphology and diet in perch.</p><p>In conclusion, the results in this thesis show that individual variation in diet and habitat choice is a common phenomenon with lots of ecological and evolutionary implications. However, there are many mechanisms involved in this phenomenon on which we are just about to start learning more about, and only further research in this area will give us the full insight.</p>

Age is often a neglected factor in ecological studies. However, age-related changes in reproduction and survival of organisms may strongly influence population dynamics. The Gotlandic population of collared flycatchers is a perfect system for studying age-related changes in the wild, as the exact age and reproductive history of most individuals is known. Collared flycatchers (Ficedula albicollis) on Gotland show the typical pattern of age-related changes in survival and reproductive success; both factors show an increase early in life and a decrease late in life. This thesis presents a broad study not only of age-related patterns of reproduction and immunity, but also proposes the mechanisms driving these patterns. My results show that in addition to survival probability and reproductive performance, reproductive costs and life-history trade-offs also change with progressing age. There is a significant increase in reproductive performance at the population level during first years of life which result from selection against low quality phenotypes. On the individual level this pattern is best explained by an optimization of reproductive effort. However, high quality individuals have higher reproductive success as early as their first breeding event and are long-lived. Thus, they seem to adopt a different strategy than lower quality, short-lived individuals. Differences in individual quality seem to be shaped by the developmental conditions experienced as nestlings. Fledglings with longer tarsi, but lower body mass become long-lived, high quality adults. Young individuals breeding for first time pay higher costs of reproduction. They also express a limited ability to reduce these costs by breeding in high quality territories when compared to middle-aged individuals. Young individuals seem to invest more into self-maintenance, whereas old individuals reduce the level of self-maintenance (measured as immune response) and redistribute their investment towards reproduction. Thus, old individuals are limited in their ability to reduce reproductive costs under favorable conditions, especially as they also senesce, which pattern is also shaped by individual quality. Variation in individual quality appears to have an strong effect on age-related survival probability, reproductive performance, reproductive costs, and even life-history decisions. Therefore, taking this factor into account in studies of life-history patterns is necessary to obtain reliable results.

This project predominantly investigated the implications of spatial heterogeneity in the ecological processes of competition and infection. Empirical analysis of spatial heterogeneity was carried out using the lepidopteran species Plodia interpunctella. Using differently viscous food media, it was possible to alter the movement rate of larvae. Soft Foods allow the movement rate of larvae to be high, so that individuals can disperse through the environment and avoid physical encounters with conspecifics. Harder foods lower the movement rate of larvae, restricting the ability of individuals to disperse away from birth sites and avoid conspecifics encounters. Increasing food viscosity and lowering movement rate therefore has the effect of making uniform distributed larval populations more aggregated and patchy. Different spatial structures changed the nature of intraspecific competition, with patchy populations characterised by individuals experiencing lower growth rates and greater mortality because of the reduced food and space available within densely packed aggregations. At the population scale, the increased competition for food individuals experience in aggregations emerges as longer generational cycles and reduced population densities. Aggregating individuals also altered the outcome of interspecific competition between Plodia and Ephestia cautella. In food media that allowed high movement rates, Plodia had a greater survival rate than Ephestia because the larger movement rate of Plodia allowed it to more effectively avoid intraspecific competition. Also the faster growth rate, and so larger size, of Plodia allowed it to dominate interspecific encounters by either predating or interfering with the feeding of Ephestia. In food that restricts movement, the resulting aggregations cause Plodia to experience more intraspecific encounters relative to interspecific, reducing its competitive advantage and levelling the survival of the two species. Spatial structure also affected the dynamics of a Plodia-granulosis virus interaction and the evolution of virus infectivity. Larval aggregation forced transmission to become limited to within host patches, making the overall prevalence of the virus low. However potentially high rates of cannibalism and multiple infections within overcrowded host aggregations caused virus-induced mortality to be high, as indicated by the low host population density when virus is presented. Also aggregated host populations cause the evolution of lower virus infectivity, where less infective virus strains maintain more susceptible hosts within the aggregation and so possess a greater transmission rate. The pattern of variation in resistance of Plodia interpunctella towards its granulosis virus was found using two forms of graphical analysis. There was a bimodal pattern of variation, with most individuals exhibiting either low or high levels of resistance. This pattern was related to a resistance mechanism that is decreasingly costly to host fitness.

Introduction: En réponse aux exigences du gouvernement fédéral en ce qui concerne les temps d'attente pour les chirurgies électives d’hanche et du genou, les Organismes Canadiens de santé ont adopté des stratégies de gestion pour les listes d'attente. Cependant, il n'existe pas actuellement aucune information disponible concernant les effets imprévus, positive ou négative, de ces stratégies. Méthodologie: Un modèle qui a été construit est tombé en panne la gestion de la chirurgie d’hanche et du genou en différentes étapes, afin d'identifier les effets imprévus possibles pour chaque étape; le modèle a été validé auprès d'un panel d'experts. Cette étude a choisi quatre études de cas en fonction de leur durabilité: un cas qui a été durable, un cas qui a été modérément durable, et deux cas peu probable d'être durable. Dans cette étude qualitative, nous avons mené 31 entretiens semi-structurés entre Novembre 2010 et Juin 2011 avec les gestionnaires, les infirmières, les thérapeutes et les chirurgiens impliqués dans la gestion des stratégies du temps d’attente pour les chirurgies électives d’hanche et du genou. Les quatre cas ont été sélectionnés à partir de trois provinces / régions. Nous avons analysé les conséquences non intentionnelles aux niveaux systémique et organisationnelle en utilisant les stratégies dans chaque contexte. Enregistrements des entrevues ont été transcrits mot à mot et soumis à l'analyse du cadre. Résultats: Les effets négatifs sont la précarité des stratégies en raison du non-récurrente financement, l'anxiété chez les patients qui ne sont pas prêts pour la chirurgie, une redistribution du temps de chirurgie vers l’orthopédie au détriment des autres interventions chirurgicales, tensions entre les chirurgiens et entre les orthopédistes et anesthésistes, et la pression sur le personnel dans le bloc opératoire et postopératoire. Conclusion: La stratégie d’implémentation aux niveaux national et local devrait prendre en compte les conséquences potentielles, positives et négatives. Il y a des conséquences inattendues à chaque niveau de l'organisation des soins de santé. Individuellement et collectivement, ces conséquences peuvent positivement et négativement affecter les résultats. Par conséquent, la planification de la santé doit analyser et prendre en compte les conséquences inattendues en termes de bonnes résultats inattendues, compromis et les conséquences négatives afin d'améliorer les résultats. / Introduction: In response to federal government requirements regarding wait times for elective hip and knee surgeries, Canadian healthcare organizations have adopted wait list management strategies. However, there is currently no information available regarding the unanticipated effects, positive or negative, of these strategies. Methodology: A model was constructed that broke down the management of elective hip and knee surgery into different steps, in order to identify the unanticipated potential effects for each step; the model was validated with a panel of experts. This study chose four case studies based on their sustainability: one case that was sustainable, one case that was moderately sustainable, and two cases considered unlikely to be sustainable. In this qualitative study, we conducted 31 semi-structured interviews between November 2010 and June 2011 with managers, nurses, therapists and surgeons involved in wait time management strategies for hip and knee surgeries. The four cases were selected from three provinces/areas. We analyzed potential unintended consequences at the systemic and organizational levels of using these strategies in each setting. Interview recordings were transcribed verbatim and subjected to framework analysis. Results: Negative effects were the strategies’ precariousness due to non-recurrent funding, anxiety in patients not ready for surgery, a redistribution of surgical time toward orthopaedics at the expense of other surgeries, tensions between surgeons and between orthopaedic surgeons and anaesthesiologists, and significant pressure on personnel in the operating suite and in post-operative care. Conclusions: Strategy implementation at the national and local levels should take into consideration any potential consequences, positive and negative. There are unintended consequences at each level of healthcare organization. Individually and jointly, these consequences can positively and negatively affect outcomes. Therefore, health planning should analyze and take into account unintended consequences in terms of serendipities, trade-offs and negative consequences in order to improve results.

公司分割制度在歐美各國已行之有年，對於企業而言分割已是進行企業重組再造的普遍管理工具，惟我國完成分割法制不過三年左右光景，因此對於我國公司分割事件與股東價值關聯性之相關研究仍付之闕如。 因此，本研究以國內上市公司為樣本，以民國91年2月企業併購法公告施行後至94年1月底為研究期間，探討上市公司分割行為、公司分割宣告對股價異常報酬率的影響及影響股價異常報酬率的關聯性。 本研究主要發現如下： 1.本研究針對公司分割進行實際案例探討，發現公司之分割活動使其財務報表之資產結構改變，資產內容重新分配，顯示分割行為對公司資產負債表會產生立即性的影響。我國上市公司從事分割行為後較分割前之每股淨值平均增加0.76元，其增加的比率約6.63%；從分割公司之淨值負債比來看，我國從事分割之上市公司因分割行為使公司之平均淨值負債比增加59.23%，其增加的比率為52.23%。 2.在公司分割宣告日，被分割公司股價具有正向的異常報酬及累積異常報酬。 3.公司分割移轉之每股土地增值稅準備金額對股價標準化異常報酬率有顯著之正向影響。 4.「業務型分割」型態相對於「不動產型分割」而言，市場給予較高的異常報酬率。

The effectiveness of land sharing and land sparing (LS/LS) approaches to conservation in the face of rising agricultural demands has been widely debated. While numerous studies have investigated the LS/LS framework from an ecological lens (yield-biodiversity relationship) the relevance of the framework to real life depends on broader considerations. Some of the key caveats include: i) limited knowledge regarding the feasibility of interventions given diverse stakeholders’ interests, ii) the social acceptability (uptake) of these contrasting strategies to direct land users, and iii) limited knowledge regarding their impacts on individuals’ livelihoods and food security. Without considering these social science dimensions proponents of the framework risk an incomplete picture that is not grounded in local realities and can paradoxically force into opposition the very conservation and development interests they seek to reconcile. Using a Companion Modelling approach, which comprises the development of a role-playing game (RPG) and an agent-based model (ABM), this thesis addressed these caveats. The research was based in the Nilgiris of Western Ghats India, a tropical agricultural system at the forest frontier. The main findings show that through engaging local stakeholders in a participatory process, plausible land use strategies that align with their objectives could be identified. Stakeholders proposed three land use interventions. Two of them resemble a form of land sparing (‘monofunctional’ landscapes) on the farms: sparing land for Wildflower Meadows or Tree Plantations while increasing yield on the remaining land. The third intervention asks farmers to accept yield penalties for Intercropping more trees on their farms, a form of land sharing (‘integrated’ landscapes). In terms of decision-making regarding the adoption of these three interventions by direct land users, the study reveals several findings. Firstly there are three main types of motivations that influence farmers’ decision to adopt interventions, in order of importance: monetary benefits, pro-environmental motivations and social norms. Secondly, land use, the type of management preferred on the farm and whether land users accept trees on the farm or not are factors that influence what type of interventions is socially acceptable on individual farms. These factors have been detected in the in-depth household survey and also validated by the RPG. When assessing the adoption of the three interventions, ex ante their implementation, using an ABM, there are some important differences observed between the interventions. Wildflower Meadows is the intervention adopted by the largest number of households, whereas Intercropping is adopted across the largest area of land. Forest Plantations is significantly more unpopular than the other two interventions. The third line of investigation, about the outcomes of adoption, has important policy implications. Adding a socioeconomic dimension to the ecological one adds a level of complexity and creates a less straightforward choice between the LS/LS strategies. None of the three interventions can provide optimal outcomes for production, aspects of biodiversity conservation, livelihoods and food security. Each intervention has indicators that score better compared to the other two interventions. The findings demonstrate that the ecological focus of the LS/LS framework is insufficient to deal with real-world complexities and lends itself to overly simplistic policy prescriptions. More meaningful policies could be achieved when bridging natural and social sciences to better understand the merits and limitations of the LS/LS approaches.

L’attention scientifique s’est récemment portée sur l’identification des mécanismes proximaux sous-tendant les compromis évolutifs;tels que les compromis existant entre croissance/reproduction et longévité. La production d’espèces réactives de l’oxygène (ROS )a été suggérée comme un candidat potentiel ,de par sa liaison étroite au métabolisme énergétique (sous-­produits du fonctionnement mitochondrial) et son caractère inévitable. Si la production de ROS excède le niveau des défenses antioxydantes, une situation de stress oxydant va en résulter et a été associé au vieillissement . Puisque la mitochondrie n’est pas uniquement la centrale énergétique de la cellule mais aussi le principal producteur de ROS, cette thèse s’est attachée à clarifier les relations entre métabolisme énergétique , fonctionnement mitochondrial et stress oxydant ; avec des études concernant l’impact d’activités coûteuses en énergie (croissance, reproduction, thermogénèse) sur l’équilibre de la balance oxydative. / In recent years, scientific attention has turned towards the identification of the mechanisms underlying the trade-­‐offs occurring between growth rate/reproductive investment and longevity. Amongst these mechanisms, the production of reactive oxygen species (ROS) appears to be a key factor due both to its universal and inevitable nature. ROS are by-­‐products of energy processing by the mitochondria. If ROS production exceeds the capacity of the various antioxidant systems, oxidative stress will occur, and the accumulation of oxidative damage over time is thought to be a potential cause of ageing. Since mitochondria are not only the powerhouse of animal cells but also the main producer of ROS, this PhD thesis aimed to clarify the relationships between mitochondrial uncoupling state (i.e. efficiency to produce ATP), energy metabolism and oxidative stress. I investigated the impact of energy-­‐demanding activities such as thermogenesis, reproduction and growth on oxidative homeostasis.

Le compromis d’allocation de l’énergie entre les fonctions concurrentielles de la reproduction et de la maintenance (et à long terme la survie) est largement tributaire de la capacité de l’organisme à acquérir des ressources dans son milieu. Les mécanismes physiologiques sousjacents aux décisions d’acquisition et d’allocation de l’énergie sont actuellement peu connus. Le but de cette thèse est d’étudier le rôle de deux hormones, la corticostérone et la prolactine, dans ces prises de décisions chez un oiseau marin longévif, le manchot Adélie (Pygoscelis adeliae), et ce, pendant une phase couteuse en énergie : la période d’élevage des poussins. Pour ce faire, nous avons conduit des approches expérimentales couplant d’une part la manipulation hormonale (augmentation des niveaux de corticostérone ou diminution des niveaux de prolactine) et la mesure du comportement en mer grâce à l’utilisation d’enregistreurs miniaturisés de l’effort de plongée. Par ailleurs, le budget temps, la condition corporelle, le régime alimentaire (analyses des isotopes stables du carbone et de l’azote) ainsi que le succès de reproduction des individus ont été considérés. A l’échelle de la plongée, nous avons observé des rôles positifs et négatifs de la corticostérone et de la prolactine, respectivement, sur le comportement de recherche alimentaire. De façon contradictoire, il semble que la corticostérone ait eu un effet négatif à plus large échelle (e.g. diminution de la durée des voyages alimentaires). La complexité de l’implication de ces deux hormones dans le compromis entre survie et reproduction est finalement discutée à la lumière de ces résultats. / The trade-off in the allocation of energy between the competitive functions of reproduction and maintenance (and survival in the long term basis) is largely dependent on the capacity of organisms to acquire resources in its environment. However, physiological mechanisms underlying decisions of energy acquisition and allocation are currently poorly known. Theaim of this PhD is to examine the role of two hormones, corticosterone and prolactin, in these decision processes in a long-lived seabird, the Adélie penguin (Pygoseclis adeliae) during an energetically costly period: the chick-rearing stage. To achieve this, we conducted experimental approaches coupling hormonal manipulation (increasing corticosterone levels ordecreasing prolactin levels) and the monitoring of at-sea behaviour by using miniaturised time-depth recorders. Moreover, time budget, body condition, diet (via stable isotopes analyses) and reproductive success of individuals were considered. At the dive scale, we observed positive and negative roles of corticosterone and prolactin on the foraging behaviour, respectively. However on the contrary, it seems that corticosterone had a negative effect at a larger scale (e.g. a decrease in at-sea trip duration). The complexity of the involvement of these hormones in the trade-off between survival and reproduction is discussed in the light of these results.

The research conducted in this dissertation studies the issues regarding the improvement of phase noise performance in a BiCMOS Silicon Germanium (SiGe) cross-coupled differential-pair voltage controlled oscillator (VCO) in a narrowband application as a result of a tail-current shaping technique. With this technique, low-frequency noise components are reduced by increasing the signal amplitude without consuming additional power, and its effect on overall phase noise performance is evaluated. The research investigates effects of the tail-current as a main contributor to phase noise, and also other effects that may influence the phase noise performance like inductor geometry and placement, transistor sizing, and the gain of the oscillator. The hypothesis is verified through design in a standard 0.35 μm BiCMOS process supplied by Austriamicrosystems (AMS). Several VCOs are fabricated on-chip to serve for a comparison and verify that the employment of tail-current shaping does improve phase noise performance. The results are then compared with mathematical models and simulated results, to confirm the hypothesis. Simulation results provided a 3.3 dBc/Hz improvement from -105.3 dBc/Hz to -108.6 dBc/Hz at a 1 MHz offset frequency from the 5 GHz carrier when employing tail-current shaping. The relatively small increase in VCO phase noise performance translates in higher modulation accuracy when used in a transceiver, therefore this increase can be regarded as significant. Parametric analysis provided an additional 1.8 dBc/Hz performance enhancement in phase noise that can be investigated in future works. The power consumption of the simulated VCO is around 6 mW and 4.1 mW for the measured prototype. The circuitry occupies 2.1 mm2 of die area. Copyright / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted