Predator reintroductions are becoming increasingly more common for multiple reasons, including assisting with the conservation of a predator species, the restoration of ecosystem functions and the economic benefits of their reintroduction for ecotourism ventures. There remains however, little knowledge on prey species responses to these predator reintroductions. As such, the reintroduction of cheetah (Acinonyx jubatus) into Samara Private Game Reserve provided an opportunity to investigate prey responses to predator reintroduction across a range of spatial and temporal scales. More specifically, the aim of this study was to investigate the effect of cheetah predation risk on habitat use and behavioural responses of the resident ungulate community. Samara is divided into “predator present” and “predator absent” sections, providing the opportunity to conduct a comparative study investigating the effect of cheetah on prey responses. It was hypothesized that different ungulate species would respond differently to the presence of cheetah, depending on differences in perceived vulnerability to cheetah predation. To address this, shifts in habitat use, and behavioural responses of the ungulate community reflected at landscape and patch scale were investigated. Overall, ungulate species have not shifted habitat use since cheetah reintroduction, this was possibly related to life history strategy constraints and the need for individuals to obtain suitable forage and therefore remain in specific habitats. While no shift in habitat use was observed for the majority of ungulate species, a shift in behaviour was observed for kudu (Tragelaphus strepsiceros) at a landscape scale, where kudu dedicated more time to vigilance and less time to foraging within the predator section. In addition, individuals within smaller kudu groups were observed to be more vigilant than individuals within larger groups of kudu within the predator section. Although the other three ungulate species monitored did not increase time spent vigilant within the predator section, they still maintained relatively high levels of vigilance, potentially as a means of social monitoring. At a patch level, ungulate species responded strongly to a predator cue as a proxy for cheetah proximity, and increased time spent vigilant with a trade-off of lower foraging effort. This vigilant response was strongest for kudu. Differences in perceived predation risk were reflected within eland (Tragelaphus oryx) and kudu species demographic classes, with juvenile eland and kudu, adult female kudu and subadult female kudu spending more time vigilant within manipulated patches than respective males of each species. Kudu were also observed adopting fine-scale behavioural responses to minimize predation risk within patches. The asymmetrical prey species response to perceived predation risk from cheetah supports the hypothesis that different species respond differently to the presence of a predator. Furthermore, this study illustrated the importance of measuring prey responses to predation risk across multiple scales and highlighted the need to replicate this study for a number of different sites where predators have been reintroduced, to better understand the range of factors influencing these predator-prey interactions.

L’innovation est une variable souvent discutée en droit de la concurrence. L’innovation prédatrice l’est beaucoup moins. Peut-être est-ce dû au fait que les termes sont euphémiques : l’innovation est généralement conçue comme étant prédatrice par nature dans la mesure où son objectif est la création ou l’amélioration d’une chose existante dans le but qu’elle surpasse la chose d’un tiers. Peut-être est-ce parce qu’étudier l’innovation et ses mécanismes est un exercice souvent décrit comme étant complexe. Peut-être est-ce parce que le développement rapide des marchés liés aux nouvelles technologies s’est accompagné d’un courant doctrinal, en Europe comme aux États-Unis, qui prône la nécessité de retirer le droit de la concurrence de cette matière. Peut-être, enfin, est-ce parce que les décisions de justice n’ont que trop peu utilisé ce vocable d’innovation prédatrice, ce qui a conduit la doctrine à n’y consacrer que peu d’études, limitant d’autant plus son utilisation par les juridictions et autorités de concurrence.Reconnaître un régime à l’innovation prédatrice est pourtant l’une des nécessités de ce début de 21ème siècle en terme de droit de la concurrence. Les pratiques qui s’y rattachent surviennent régulièrement et visent à supprimer la compatibilité des technologies d’un tiers avec celles d’une entreprise dominante ou à altérer le fonctionnement de technologies concurrentes. Le droit de la concurrence doit y apporter une réponse. L’enjeu est considérable, mais il n’en demeure pas moins que le concept d’innovation prédatrice – que nous définissons comme l’altération d’un ou plusieurs éléments techniques d’un produit afin de restreindre ou éliminer la concurrence – est aujourd’hui ignoré ou mal compris du plus grand nombre.Les règles ainsi imaginées doivent être communes à plusieurs systèmes juridiques dans la mesure où les pratiques d’innovation prédatrice sont généralement mises en œuvre sur plusieurs continents à la fois. Notre étude prend le parti d’analyser les droits européen et nord-américain de la concurrence parce que leurs racines sont homologues et parce que les pays concernés justifient du PIB le plus élevé au monde.Le régime que nous exposons s’articule autour de deux étapes principales. Il s’agit pour commencer de rejeter toutes les règles per se en la matière, parce qu’elles ne répondent pas aux défis nouveaux du droit de la concurrence. Seule l’application d’une règle de raison structurée organisée autour de trois filtres permet le prononcé de décisions adaptées dans chaque cas d’espèce tout en éliminant les demandes pour lesquels aucun risque concurrentiel n’est envisagé.Un test amélioré de l’absence de justification économique doit ensuite être mis en œuvre pour toutes les pratiques qui ont un effet anti-concurrentiel au moins possible sur le plan théorique – celles qui ont passé les filtres – et qui méritent donc d’être analysées. Ce test, qui permet de ne condamner que les seules pratiques anti-concurrentielles, autorise par conséquent l’élimination des erreurs de type I et II. Il participe également d’une simplification d’un droit de la concurrence devenu parfois illisible. Une nouvelle étude – sur la base du test proposé – des plus grandes affaires européennes et nord-américaines en matière d’innovation prédatrice permet d’illustrer son efficacité.Il nous est enfin apparu nécessaire de traiter de la question de la sanction – ou remèdes – des pratiques d’innovation prédatrice. Il ressort de notre étude que le respect du choix stratégique de l’entreprise en matière d’interopérabilité doit être reconnu comme un principe immuable. Également, les modes alternatifs de sanction ne doivent pas être systématisés et le développement de la « soft law » doit prendre une direction nouvelle qui soit davantage centrée sur l’accompagnement des entreprises très innovantes. / Innovation is often discussed in antitrust law. Predatory innovation is less considered. Perhaps it is because predatory innovation is considered euphemistic: innovation is generally seen as being predatory by nature insofar as its objective is the creation or improvement of an existing product in order to surpass the product -another. Perhaps it is because studying innovation and its mechanisms is often described as a complex exercise. Perhaps it is because the rapid development of high-tech markets, in Europe and in the United States, was accompanied by a doctrinal movement, which preached the need to remove antitrust laws. Perhaps, finally, since court and competition authorities have only minimally termed predatory innovation, this has led the doctrine to devote minimal studies, thus resulting in the limiting of its use by courts and competition authorities.Recognizing the existence of predatory innovation is one of the great necessities of the early 21st century regarding antitrust law. Predatory innovation practices occur regularly and aim at removing the compatibility of third party technologies with those of a dominant firm or at impairing the functioning of competing technologies. As of today, antitrust law provides no answer to these strategies. The stakes are high; the concept of predatory innovation – which we define as the alteration of one or more technical elements of a product to limit or eliminate competition – is currently ignored and/or misunderstood greatly.This thesis focuses on European and North American antitrust laws because their roots are homologous and these countries represent the highest GDP in the world. With predatory innovation practices frequently implemented on several continents at once, overarching rules need to be extended to several legal systems.The regime we exhibit is organized around two main stages:The first implies to reject every related per se rule because they do not meet the new challenges met by antitrust law. Only the diligent implementation of a structured rule of evaluation organized around three filters will ensure appropriate decisions and the elimination of requests for which no antitrust issues are envisaged.Once evaluated by the three filters, an improved test of no economic sense must then be applied to all practices which have theoretical anti-competitive effects and determined fit to be further analyzed. This test, which specifically condemns anti-competitive practices, is a simplification of currently unreadable antitrust law and when applied will lead to the elimination of type I and type II errors. A new study – based on the proposed test – of the most notorious European and North American predatory innovation cases illustrates its effectiveness.The second addresses sanctions – or remedies – to predatory innovation practices. It appears that respecting the strategic choice of companies in terms of interoperability should be recognized as an immutable principle. Also, negotiated procedures shall not be systematized and the development of "soft law" must take a new direction aiming at supporting highly innovative companies.

European immigrants once regarded wolves as the "devil in disguise" (Lopez, 1978, p.40). With our growing awareness of other cultural perspectives and flourishing body of scientific knowledge with regard to wolves' behavior, our perceptions of wolves have become more complicated and nuanced. Our collective awareness of the environment in which we live also gathers complexity. I examine these issues in this study. Wolves are returning to Oregon. The arrival of wolf B-45 in 1999 heralded the beginning of the return of wild wolves to Oregon. More wolves are expected to cross the border as young sub-adults disperse from the growing population in Idaho. This study explores our perceptions of wolves using empirical, qualitative methodology. Running in parallel with this main goal, I also seek to understand how these perceptions relate on a larger scale to the ways we understand nature. In exploring these questions qualitatively, I seek to answer the following questions: (a) What ways can story play a role in defining people’s perceptions, in particular, of wolves? (b) What lessons can be learned to inform future ecological educators' work to communicate on this or other similarly complex topics? (c) What is the collective story that we can tell each other on the eve of wolves' presence in the Oregon landscape becoming an acknowledged reality once again? (d) Finally, how can what is learned inform future ecological educational programs regarding wolves in the state? This study explores the above questions. In considering people's perceptions, I attempt to examine whether the desires to exterminate wolves are really gone. Perhaps, as we learn more about the complex ways that wolves interact in the landscape and the various ways that humans react to the idea of wolves, we may recognize the greater complexities in the ways we inter-relate with them.

Niche separation may be the key to promoting the long-term coexistence of introduced and native species. Physical alterations to the environment (habitat manipulation) or re-introducing native species to former habitats can exploit the maladapted traits of introduced species to create a refuge for native species. No two species have identical niches because evolutionary constraints differ between species with different evolutionary histories. Our objectives were to determine if cold temperatures could promote coexistence between native least chub and introduced western mosquitofish. We used individual scale and population scale experiments to test four hypotheses: 1) colder temperatures would reduce the aggressive behavior and predatory effects of western mosquitofish on least chub, 2) colder temperatures would reduce the effect of western mosquitofish on the habitat use, activity, and feeding of least chub, 3) western mosquitofish would not be able to overwinter without warm refuges, and 4) western mosquitofish reproduction would be delayed or absent at colder temperatures, whereas colder temperatures would not inhibit least chub recruitment. At the individual scale cold temperatures reduced the aggression and predation of western mosquitofish on least chub. However at the population scale there was little recruitment in the cold treatment and juvenile least chub did not survive the winter in the cold treatment. Adult least chub successfully overwintered at freezing temperatures whereas western mosquitofish had no recruitment in the cold treatment during the summer and no western mosquitofish survived the winter. There is adequate niche separation among the adults to promote coexistence but the juveniles of both species require warm habitat in the spring and summer to survive freezing winter temperatures. Habitat manipulation may reduce the availability of warm winter refuges for western mosquitofish while leaving warm habitats during the spring for least chub spawning and recruitment. Transplanting least chub to former cold habitats could eliminate western mosquitofish because of niche separation between the species along a temperature gradient. We suggest that the niche separation hypothesis has general application for the restoration of a variety of threatened native species.

The presence of toxic order ow and predatory HFT strategies in a multi-market setting are scarcely researched in the academic world. This thesis studies the toxicity levels of a set of markets by examining unconsolidated quote data and firm specific trade data. A method for deducing the markets toxicity levels is presented along with proxies for toxic order ow, namely: changes in spread and quoted volume, following a trade in a given market. We find both signs of toxicity and different toxicity levels between the markets. However, the results are lacking in statistical significance but they show that this field is of great interest for further research. Also, the methods proposed for deducing the toxicity levels are rudimentary but could serve well as a premise for further development. / Närvaron av toxic order flow och predatoriska HFT-strategier i en flermarknadsmiljö är föga studerat i den akademiska världen. Denna avhandling studerar detta på en uppsättning marknader genom att undersöka okonsoliderad quote data och firma specifika trades, och på så vis ta fram marknadernas toxicity-nivåer. En metod för att fastställa marknadernas toxicity-nivåer presenteras tillsammans med proxys för toxic order flow, mer specifikt: förändringar i spread och quotad volym, efter en handel på en given marknad. Vi finner både tecken på toxicity och olika toxicityniv åer mellan marknaderna. Resultaten saknar dock statistisk signifikans men de visar ändå på att detta område är av stort intresse för ytterligare forskning. De metoder som föreslås för att fastställa toxicity-nivåerna är rudimentära, men kan tjäna som en utgångspunkt för vidare utveckling.

No description available.

No description available.

Over the last years, varieties of technologies for biofilm analysis were developed and established. They work on different principles and deliver information about biofilms on different information levels. In this work, chip-calorimetry was applied as an analytical tool that measures heat produced from biofilms. Any change of metabolism in biofilms is reflected by a changed heat flow. The heat, which is the integral of the heat flow vs. time, is quantitatively related to the growth stoichiometry of the biofilm, as described by the Hess’ Law. The heat flow is related to the growth kinetics with the reaction heat as proportionality factor. The results from the calorimetric measurement thus, deliver general information about growth stoichiometry and kinetics. The other interpretation of calorimetric results bases on the assumed proportionality between heat flow and oxygen consumption rate (- 460 kJ/mol ). This ratio is called oxycaloric equivalent. Because in case of aerobic growth the majority of oxygen is consumed in catabolic processes during the electron transport phosphorylation, calorimetry is assumed to provide information about the catabolic side of the metabolism. The newly developed chip-calorimeter applied in this work is much more suitable for biofilm studies compared to conventional microcalorimeters due to the flow-through design of the calorimetric chamber. The measurement of undisturbed growing biofilms and the comparison with conventional biofilm analysis tools (i.e. plate counts, confocal laser scanning microscopy (CLSM), and the determination of intermediates’ concentrations (e.g. ATP)) demonstrate the proper functionality of the calorimetric method and the related cultivation procedure by delivering measurement results in the range of literature values. However, when the biofilms were challenged with antimicrobial agents i.e. antibiotics, bacteriophage, and predatory bacteria, the calorimetric results surprisingly deviated from the reference analyses. By combining the results of the calorimetric and reference analyses, additional information about the antimicrobial effects on biofilms can be acquired. Combination of heat measurement and plate counts, which is one of the most conventional approaches, demonstrated that antimicrobials (especially the bactericidal acting kanamycin) could cause the loss of culturability while the cells were still metabolically active. The measurement of ATP content resulted in values out of the typical range, which indicated that antimicrobial treatments disturbed the cellular ATP regulation and the ATP concentration was no longer linearly correlated to the cell number. ATP measurements are therefore not suitable for antimicrobial susceptibility testing. The comparison of heat profiles with the biovolume determined by quantification of microscopic images shows an elevated cell specific heat production rate after the introduction of some antimicrobials (antibiotics and bacteriophage). In case of antibiotics, this can be explained as a consequence of the bacterial defense mechanisms. Most of the described defense mechanisms against antibiotics need biological energy and therefore drive the electron transport phosphorylation (ETP). In case of biofilm treatments with bacteriophage, the trigger of increasing ETP might be the synthesis of phage proteins, hull material, and genetic information molecules. In aerobic conditions, oxygen is used as terminal electron acceptor. Elevated ETP leads therefore to an increase in oxygen consumption, which correlates to the heat production using oxycaloric equivalent as a factor. These correlations explain the increase of cell specific heat productions as biofilms were challenged by antibiotics and bacteriophage. However, also a decrease of specific heat production was observed (in case of predatory bacteria). Here, the predatory bacteria activity caused various damages in host cells, including the interruption of ETP. With these experiments, chip-calorimetry was demonstrated as a promising complementary tool in biofilm research, which provides deeper insights about metabolic activity and alterations. It benefits from the noninvasive handling and the online, real-time measurement that allow the method to be applied for monitoring purposes. Furthermore, its miniaturized dimension allows easy integration in more complex analytic systems and also reduces experiment costs with minimal media/chemical consumption. This thesis also demonstrates the potential development of chip-calorimetry to be more suitable for routine analyses. The use of superparamagnetic beads as matrix to grow biofilms allows regulated transfer of biofilm samples into and from the measurement chamber. This was an initial step towards automation and higher-throughput analysis. One further outcome of the thesis is based on the highly interesting fact about the elevated heat production rate of the host cells induced by the phage infection observed in the chip- calorimetric experiments. The volume specific detection limit of the chip-calorimeter is lower compared to a commercial microcalorimeter. Thus, the infection effect of phages was additionally measured in microcalorimeter to get better quantitative information about the thermal effect of the infection. The results showed that the immediate heat increase after the addition of phage into the solution of the host cells appeared to be quantitatively related to the infection factor, MOI (Multiplicity of Infection). Unfortunately, microcalorimetric measurements in closed ampoules are often subjected to the oxygen limitation. Thus, this problem of microcalorimetric measurement has been addressed. The combination of experimental results and mathematical modeling showed that the rate of metabolism in the static ampoules is defined by the diffusion rate of oxygen into media. This factor has to be considered while designing biological experiments in closed calorimetric measuring chambers and interpreting the calorimetric results for their biological meaning. Some possible solutions to overcome the oxygen bioavailability problem are e.g. to design the experiments with low biomass, or by using media with elevated density to float the biomass at the interface to air and thus to reduce the diffusion path.

Les prix bas suscitent de nombreux débats en droit économique. Bien que l'opportunité de leur régulation ne semble guère sujette à caution, la liberté de pratiquer une concurrence par les prix est indissociable de la liberté de commerce. Les prix bas apparaissent donc licites par principe. L'interdiction de la revente à perte fait alors figure d'exception en obligeant le législateur à déterminer un prix minimal. Lier cette prohibition au principe de non discrimination a longtemps présenté l'indéniable avantage de contourner une si flagrante difficulté. Cela a toutefois régulièrement mis le législateur au défi de concilier l'effectivité de la sanction avec la possibilité d'une réelle négociation des conditions de vente du fournisseur. La négociabilité retrouvée le place plus que jamais au défi de concilier cette effectivité avec la liberté contractuelle : puisque tout est déductible, tout doit être aisément justifiable et contrôlable. / Low prices have caused much controversy. Although the need of regulation is actually not an issue in economic analysis of law, the freedom to practise competition based on prices is linked to the freedom of trade. Consequently, low prices appear to be lawful as a rule. Prohibiting to resell at a loss is quite exceptional since it requires from the law-maker to fix a minimum price. Linking the prohibition to the principle of non-discrimination has allowed to get round such a problem for a long time. Nevertheless, it regularly challenged the law-maker to associate the effectiveness of the penalty with the possibility for the retailers to really negociate the suppliers' sales conditions. Removing the principle of non-discrimination challenges the law-maker to link the effectiveness of the penalty with the freedom of contracts, since everything is deductible, everything must be easily justified and controlled.

Abuse of the Dominant Position by Prohibited Pricing Activities Abstract This thesis analyzes selected pricing practices of dominant undertakings namely predatory pricing, margin squeeze and excessive pricing. These practices may, under certain circumstances, constitute an abuse of the dominant position. The aim of the thesis is to focus on problematic aspects of each of these practices, on explanation of various legal and economic tests used to prove that certain pricing policy constitutes an abuse of dominant position and on the description of conditions that have to be met in order to consider such practice contrary to the competition law of the Czech Republic and the European Union. The thesis is composed of four chapters. In Chapter One a brief introduction to the competition law itself and to the analyzed matter is given. Chapter Two describes basic terminology used when dealing with cases of abuse of a dominant position such as basic legal concept of the abuse itself, definition of an undertaking and a competitor according to the EU law and the Czech law respectively, delimitation of a relevant market and finally definition of a dominant position. Chapter Three is oriented on the selected pricing practices of dominant undertakings. This Chapter is subdivided into three parts each of which is dealing...