Clonally variant gene expression (CVGE) is a common survival strategy used by many pathogens, including the malaria parasite Plasmodium falciparum. Among the genes that show CVGE are several members of the clag and eba families. The active or repressed state of clag3.1, clag3.2 and eba‐140 is transmitted epigenetically and is controlled by the euchromatic or heterochromatic state of bistable chromatin domains, characterised by H3K9ac and H3K9me respectively. Both of these modifications are maintained throughout the asexual cycle to transmit epigenetic memory. We have characterised CVGE on a genome‐wide level and found that it is widespread. Using clag3.2 in proof‐of‐principle experiments, we demonstrate that CVGE for genes other than var can be reproduced in an episomal system and provide preliminary evidence that CVGE is regulated by the spontaneous formation of facultative heterochromatin. The mutually exclusive expression of clag3.1 and clag3.2 is also addressed, including the characterisation of a neighbouring noncoding RNA. / La variació clonal en l'expressió gènica (CVGE) és una estratègia de supervivència comú utilitzada per molts patògens, incloent el paràsit de la malària Plasmodium falciparum. Entre els gens que mostren CVGE hi ha diversos membres de les famílies clag i eba. L'estat actiu o inactiu de clag3.1, clag3.2 i eba‐140 es transmet epigenèticament i és controlat per l'estat eucromatínic o heterocromatínic de dominis de cromatina biestables, caracteritzats respectivament per H3K9ac i H3K9me. Ambdues modificacions es mantenen durant tot el cicle asexual per transmetre la informació epigenètica. També hem caracteritzat la CVGE a nivell de tot el genoma, i hem vist que afecta un gran nombre de gens. Experiments preliminars amb clag3.2 ens demostren que la CVGE de gens diferents que var es pot reproduir en un sistema episomal I proporcionen evidència preliminar de què la CVGE està regulada per la formació espontània d’heterocromatina facultativa. També s’ha estudiat l'expressió mútuament exclusiva de clag3.1 i clag3.2, incloent la caracterització d’un ARN no‐codificant veí.

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Magister Legum - LLM / There is a growing interplay of competing realities facing the international community in the general areas of innovation, technological advancement and overall economic development. The highly industrialised wealthy nations, largely located on the Northern hemisphere are on the one hand undoubtedly at the forefront in global research, technology and infrastructure development. The developing and least developed countries on the other hand are mostly situated on the Southern hemisphere. They are not as wealthy or technologically advanced as their Northern counterparts, but are naturally endowed with unique variations of plant, animal and micro-organism species occurring in natural ecosystems, as well as the traditional knowledge on how to use these unique species. This knowledge has been adjudged to be responsible for the sustainable maintenance of the earth biodiversity. Increasing exploitation of biodiversity spurred on by the competing realities identified above, has left the earth in a present state of alarm with respect to the uncontrolled loss of biodiversity. The traditional knowledge of local peoples has significantly offered leads to research institutes from the North in developing major advancements in drugs, cosmetics and agriculture. Little or no compensation has however been seen to go back to the indigenous communities and countries that provide resources, and indicate various possibilities through their traditional knowledge to the use of such resources. Efforts by some biodiversity rich countries to ddress this trend through legislation developed in accordance with the principles of the Convention on Biological Diversity have been frustrated due to the inability to enforce their domestic laws outside their borders. Theft of genetic resources and its associated traditional knowledge from such countries has therefore remained a major challenge. Against this backdrop, and on the insistence of biodiversity-rich developing countries, an international regime on access and benefit sharing was negotiated and its final text adopted in 2010. This international regime is as contained in the Nagoya Protocol. This research sets out to examine whether the Nagoya Protocol offers a final solution to the protection of traditional knowledge associated with biodiversity in biodiverse countries. It further examines the importance of domestic legislation in achieving the objectives of the Protocol. The research has been tailored to African biodiverse countries, and seeks these answers within the context of Africa. / South Africa

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This dissertation contains a comprehensive analysis of both non-coupled and mutually coupled switched reluctance motors with concentrated windings for an electric bicycle traction application. Multiple pole configurations are analyzed and compared for each motor type. Includes magnetic design, thermal analysis, and structural analysis. A prototype is designed, manufactured, and validated. / This thesis discusses the design of both a conventional non-coupled switched reluctance motor (CSRM) and a mutually-coupled SRM (MCSRM) for an exterior rotor e-bike application. Several novel pole configurations were analyzed for each machine type, and the performance of the final CSRM and MCSRM designs were compared for this application. A commercially available e-bike permanent magnet synchronous motor (PMSM) was purchased, reverse engineered, and validated to define the geometry constraints and performance targets for the designs. Since switched reluctance motors do not use rare-earth permanent magnets, they are often seen as a potential low-cost alternative to permanent magnet machines. The goal of this research is to explain the relative advantages of CSRMs and MCSRMs when compared to PMSM machines for a direct-drive e-bike application. The final CSRM and MCSRM designs are analyzed in detail; electromagnetic, controls, thermal, and structural considerations are all studied. A prototype of the final CSRM design was manufactured and validated experimentally, using a dynamometer setup. The finalized CSRM design is shown to be competitive with the PMSM machine when considering torque output, and is superior in terms of peak efficiency, and high speed torque performance. However, the CSRM noise output and torque ripple were not compared to the PMSM, and a less-common asymmetric-bridge converter is required for the CSRM, which may hinder the ability for the machine to be implemented into existing e-bike packages. The high speed torque performance of the MCSRM is shown to be inferior to both the CSRM and PMSM, as is the torque quality and efficiency. The MCSRM is shown to be highly resistant to saturation which gives it the potential for high torque output at low speed (if thermal limits are not breached), though low saturation levels also contribute to low machine power factor. The MCSRM may be better suited to lower speed, high torque applications, for this reason. / Thesis / Doctor of Philosophy (PhD) / This thesis studies the design process and analysis of two different motor types, for an electric bicycle application. They are designed to replace a commercially available permanent magnet synchronous motor (PMSM). This type of motor is typically expensive due to the rare-earth magnet material it requires. The two motors discussed in this thesis are switched reluctance motors (SRMs), which do not require magnet material, and thus have the potential to save cost (in addition to other benefits). One of the SRMs has magnetic fields that are independently controlled (CSRM), and one has fields that are controlled together to produce torque (MCSRM). The magnetics, control, thermal, and structural aspects of the CSRM and MCSRM are studied in detail. Novel geometry considerations (i.e. novel pole configurations) which impact the magnetics of each machine are compared to find the best-performing configuration for each machine type.

This article addresses the issue referred to the remedies of the insurance contract for the non-payment of the premium. t hrough an analysis of the previous and current legislation, the author examines the consequences of the non-payment of the insurance premium in the contractual relationship. By recognizing the protective nature of the legislation in favor of the insured as the weak party, three specific contractual remedies are identified: The suspension of coverage, the termination of the contract and the the extinction of the contractual relationship by inaction of the parties. / El presente artículo aborda la temática referida a los remedios del contrato de seguro ante el incumplimiento del pago de la prima. r ealizando un análisis de los remedios que planteaba la anterior legislación así como la vigente, el autor examina las consecuencias que tiene el incumplimiento del pago de la prima en la relación contractual. Reconociendo el carácter tuitivo de la legislación en favor del asegurado como parte débil, se identifica tres remedios contractuales específicos: la suspensión de la cobertura, la resolución del contrato y la extinción del contrato por inacción de las partes.

Pour d non puissance d’un nombre premier, le nombre maximal de bases deux à deux décorrélées d’un espace de Hilbert de dimension d n’est pas encore connu. Dans ce mémoire, nous commençons par donner une construction de bases décorrélées en lien avec une famille de représentations irréductibles de l'algèbre de Lie su(2) et faisant appel aux sommes de Gauss.Puis nous étudions de façon systématique la possibilité de construire de telle bases au moyen des opérateurs de Pauli. 1) L’étude de la droite projective sur Zdm montre que, pour obtenir des ensembles maximaux de bases décorrélées à l’aide d'opérateurs de Pauli, il est nécessaire de considérer des produits tensoriels de ces opérateurs. 2) Les sous-modules lagrangiens de Zd2n, dont nous donnons une classification complète, rendent compte des ensembles maximalement commutant d'opérateurs de Pauli. Cette classification permet de savoir lesquels de ces ensembles sont susceptibles de donner des bases décorrélées : ils correspondent aux demi-modules lagrangiens, qui s'interprètent encore comme les points isotropes de la droite projective (P(Mat(n, Zd)²),ω). Nous explicitons alors un isomorphisme entre les bases décorrélées ainsi obtenues et les demi-modules lagrangiens distants, ce qui précise aussi la correspondance entre sommes de Gauss et bases décorrélées. 3) Des corollaires sur le groupe de Clifford et l’espace des phases discret sont alors développés.Enfin, nous présentons quelques outils inspirés de l’étude précédente. Nous traitons ainsi du rapport anharmonique sur la sphère de Bloch, de géométrie projective en dimension supérieure, des opérateurs de Pauli continus et nous comparons l'entropie de von Neumann à une mesure de l'intrication par calcul d'un déterminant. / For d not a power of a prime, the maximal number of mutually unbiased bases (MUBs) in a d-dimensional Hilbert space is still unknown. In this thesis, we begin by an original building of MUBs by means of Gauss sums, in relation with a family of irreducible representations of the Lie algebra su(2).Then, we sytematically study the possibility of building such bases by means of Pauli operators. 1) The study of the projective line on Zdm shows that, in order to obtain maximal sets of MUBs, tensorial products of these operators are in order. 2) Lagrangian submodules of Zd2n, of which we give a complete classification, account for maximally commuting sets of Pauli operators. This classification enables to know which of these sets are likely to yield unbiased bases. They correspond to Lagrangian half-modules that can be interpreted as the isotropic points of the projective line (P(Mat(n, Zd)²),ω). Hence, we establish an isomorphism between the unbiased bases thus obtained and distant Lagrangian half-modules, which precises by the way the correspondance between Gauss sums and MUBs. 3) Corollaries on the Clifford group and the finite phase space are then developed.Finally, we present some tools inspired by the previous study. We deal with the cross-ratio on the Bloch sphere and projective geometry in higher dimension, Pauli operators with continuous exponents and we compare von Neumann entropy with a determinantal measure of entanglement

本研究使用美國、德國、英國股票指數期貨之日內交易資料，從報酬率中分離出連續波動度與跳躍項，再以MLE法估計Hawkes相互激勵過程之參數，衡量跨市場跳躍傳染現象。擴展文獻中僅兩市場的分析至三市場模型，更能從整體的角度解釋市場間的關係及跳躍傳染途徑。實證結果顯示，美國能直接影響其他市場，而其他市場反過來不易干涉美國，呈現非對稱影響效果。歐洲兩國能互相傳染，英國對德國的影響較大，也更有能力影響美國，稱英國為歐洲的影響輸出國，德國為歐洲的影響輸入國。

Title: Using Carrots to Bring Peace? Negotiation and Third Party Involvement Author: Martina Klimesova 284 p. (+references and appendices) March 2011 How to make peace? This dissertation answers what impact third party incentives have on peace negotiation, more specifically on negotiation strategies in internal armed conflicts based on self-determination grievances. This study further assesses when the ripest time for the employment of incentives is, and in what way external incentives have an impact on possible negotiation asymmetries. Incentives in the following negotiation processes were analyzed: GoSL-LTTE in Sri Lanka (Eelam, 2002-03; 2006), GoI-GAM in Indonesia (Aceh, 2000-03; 2005), and the GRP-MILF in the Philippines (Mindanao, 2001-08). The findings indicate that those third party incentives which are linked to the core conflict issues are most likely to have some impact on the negotiation, but that committed pro-process leadership by the conflicting parties is also a necessity. The research also indicated that third parties have only limited options in employing incentives that can have an impact on the core conflict issues; and that, in any case, they are rarely willing to pursue such options. Committed strong leadership, presence of ripeness (far more frequently stipulated by an MHS than MEO),...

This dissertation is concerned with the potential multistability of protein concentrations in the cell that can arise in biochemical networks. That is, situations where one, or a family of, proteins may sit at one of two or more different steady state concentrations in otherwise identical cells, and in spite of them being in the same environment. Models of multisite protein phosphorylation have shown that this mechanism is able to exhibit unlimited multistability. Nevertheless, these models have not considered enzyme docking, the binding of the enzymes to one or more substrate docking sites, which are separate from the motif that is chemically modified. Enzyme docking is, however, increasingly being recognised as a method to achieve specificity in protein phosphorylation and dephosphorylation cycles. Most models in the literature for these systems are deterministic i.e. based on Ordinary Differential Equations, despite the fact that these are accurate only in the limit of large molecule numbers. For small molecule numbers, a discrete probabilistic, stochastic, approach is more suitable. However, when compared to the tools available in the deterministic framework, the tools available for stochastic analysis offer inadequate visualisation and intuition. We firstly try to bridge that gap, by developing three tools: a) a discrete `nullclines' construct applicable to stochastic systems - an analogue to the ODE nullcines, b) a stochastic tool based on a Weakly Chained Diagonally Dominant M-matrix formulation of the Chemical Master Equation and c) an algorithm that is able to construct non-reversible Markov chains with desired stationary probability distributions. We subsequently prove that, for multisite protein phosphorylation and similar models, in the deterministic domain, enzyme docking and the consequent substrate enzyme-sequestration must inevitably limit the extent of multistability, ultimately to one steady state. In contrast, bimodality can be obtained in the stochastic domain even in situations where bistability is not possible for large molecule numbers. We finally extend our results to cases where we have an autophosphorylating kinase, as for example is the case with $Ca^{2+}$/calmodulin-dependent protein kinase II (CaMKII), a key enzyme in synaptic plasticity.