The elections in South Africa are contested by multiple political parties appealing to a diverse population that comes from a variety of socioeconomic backgrounds. As a result, a rich source of discourse is created to inform voters about election-related content. Two common sources of information to help voters with their decision are news articles and tweets, this study aims to understand the discourse in these two sources using natural language processing. Topic modelling techniques, Latent Dirichlet Allocation and Non- negative Matrix Factorization, are applied to digest the breadth of information collected about the elections into topics. The topics produced are subjected to further analysis that uncovers similarities between topics, links topics to dates and events and provides a summary of the discourse that existed prior to the South African general elections. The primary focus is on the 2019 elections, however election-related articles from 2014 and 2019 were also compared to understand how the discourse has changed. / Mini Dissertation (MIT (Big Data Science))--University of Pretoria, 2019. / Computer Science / MIT (Big Data Science) / Unrestricted

Structural health monitoring (SHM) systems have been technologically advancing over the past few years. Improvements in fabrication and microelectronics allow the development of highly sophisticated sensor arrays, capable of detecting and transmitting an unprecedented amount of data. As the complexity of the hardware increases, research has been performed in developing the means to best utilize and effectively process the data. Algorithms from other computational fields are being introduced for the first time into SHM systems. Among them, the artificial neural network (ANN) and artificial immune systems (AIS) show great potential. In this thesis, features are extracted out of the acceleration data with the use of discrete wavelet transforms (DWT)s first. The DWT coefficients are used to calculate energy ratios, which are then classified using a neural network and an AIS algorithm known as negative selection (NS). The effectiveness of both methods are validated using simulated acceleration data of a four story structure exhibiting various damage states via computer simulation.

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The thesis is focused on remitting lead-acid segments of partial charge mode which simulates the conditions in HEV. The experimental cells were submitted to different pressures on the electrode system. The main aim of the thesis was to minimize the irreversible sulphating of the negative electrodes, which are in the PSoC regime limiting in the overall life of lead-acid accumulators. All cells were submitted to measurement of the negative electrode potentials, resistance of active materials, contact resistance of the grid – the active material and measurements of pressure changes during three PSoC cycles.

The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries and shows possible ways of sorting from different points of view. Thesis describes construction of lead-acid batteries, parameters of lead-acid batteries, electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. In the next part of the thesis is described the production of a set of experimental electrodes for electrochemical workplace resources. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.

Parmi les sous-types moléculaires de cancers du sein, le cancer du sein triple-négatif (TNBC) est caractérisé par un très mauvais pronostic et ne bénéficie actuellement d’aucune thérapie ciblée efficace. Dans ce projet, nous avons analysé le profil de certaines altérations oncogéniques dans les tumeurs TNBC et évalué le potentiel thérapeutique de leur ciblage à l’aide des modèles de xénogreffes (PDX).Nous avons d'abord démontré que le récepteur à activité tyrosine kinase RET est surexprimé dans une sous-population de tumeurs du sein TN et HER2+. Le ciblage de RET par son inhibiteur Vandetanib a été testé in vivo dans trois modèles de PDX TNBC et un modèle de PDX HER2+ caractérisés par des niveaux différents d’expression de RET et d’EGFR (les cibles principales du Vandetanib). Le Vandetanib a induit une régression tumorale dans les trois modèles de PDX surexprimant RET ou EGFR. L’effet du Vandetanib a été associé à une inhibition de la voie MAPK, une inhibition de l'angiogenèse et une induction de la nécrose.Nous avons également étudié les altérations de la voie PI3K/AKT/mTOR dans une large série de PDX de cancers du sein incluant des PDX TNBC. La voie PI3K/AKT/mTOR a été trouvée activée dans le cancer du sein triple-négatif. L’altération principalement retrouvée dans cette voie est la perte des deux suppresseurs de la voie, PTEN et/ou INPP4B. Sept des quinze modèles de PDX triple-négatifs testés ont montré une réponse à l’Everolimus. L'analyse des tumeurs traitées a montré que la phosphorylation post-traitement d’AKT est significativement plus fréquente dans les modèles répondeurs par rapport aux non-répondeurs. En conclusion, mon travail de thèse a permis de montrer que le Vandetanib et l'Everolimus pourraient être efficaces pour traiter le cancer du sein triple-négatif. Des études complémentaires sont nécessaires pour valider les biomarqueurs prédictifs de réponse à ces deux thérapies ciblées. / Among breast cancer subtypes, Triple-negative breast cancer (TNBC) has a very poor prognosis. There are currently no known targeted therapies for this subgroup of patients. In this project, we analyzed the profile of certain oncogenic alterations in the TN tumors and evaluated in vivo the therapeutic potential of targeting these alterations in TNBC.We first demonstrated that the tyrosine kinase receptor RET is overexpressed in a subset of TN and HER2+ tumors. Targeting RET by his inhibitor Vandetanib was tested in vivo in three PDX models of TNBC and one model of HER2+ BC with different expression levels of RET and EGFR. Vandetanib induced tumor regression in the three PDX models with high expression of RET or EGFR. Vandetanib effect was associated with inhibition of MAPK pathway, inhibition of angiogenesis and induction of necrosis. PI3K pathway alterations were investigated in an important number of BC PDX including TNBC PDX. PI3K pathway was shown to be activated in TNBC PDX possibly by the loss of the two pathway suppressors, PTEN and/or INPP4B. Treatment by Everolimus induced response in seven among the fifteen TNBC PDX tested. Analysis of treated tumors showed that post-treatment phosphorylation of AKT was more pronounced in responder PDX. The combination of Everolimus with chemotherapy was tested in one PDX and resulted in increased efficacy.In conclusion, in this work we showed that Vandetanib and Everolimus could be effective in treating TNBC. Further investigations are still needed to validate response related biomarkers.

abstract: When consumers find that something critically out of the ordinary has occurred, they direct attention to evaluate such a critical incident more closely. The results of this evaluation may put consumers on a switching path or it might lead them to engage in unfavorable behaviors from the perspective of the organization, such as engaging in negative word-or-mouth online. The negative consequences of some product (goods or services) failures go beyond simple product attribute defects, leading customers to terminate the relationship with the organization. This dissertation, which is composed of three essays, investigates how consumers engage in negative word-of-mouth on social media channels in response to their various product failures and explores an important relationship event of betrayal, which can be triggered by certain product failures. It investigates how betrayal is perceived by customers and influences a range of their behaviors across business-to-consumer and business-to-business contexts. / Dissertation/Thesis / Doctoral Dissertation Business Administration 2019

Depuis les origines de la psychanalyse, le problème de l’hallucinatoire est étroitement lié au problème du fonctionnement de l’inconscient. Dans la métapsychologie « première topique », le modèle de la réalisation hallucinatoire de désir explique autant le fonctionnement du nourrisson (hallucination primitive), que celui du rêve et de la névrose de transfert. Dans Construction dans l’analyse, Freud propose toutefois une hypothèse alternative : l’hallucinatoire peut véhiculer la re- présentation, dans la cure, de noyaux irreprésentables de vérité historique. En s’appuyant sur les réflexions de plusieurs auteurs post-freudiens (Winnicott, Green, Roussillon...), l’auteur développe l’héritage freudien en essayant de l’inscrire dans un modèle capable d’intégrer l’intrapsychique et l’intersubjectif. Il avance et discute l’hypothèse de l’existence d’un fond hallucinatoire du psychisme, régi par la compulsion de répétition, qui re-active les toutes premières expériences relationnelles du sujet. Lorsque la rencontre originaire avec l’objet échoue, les traces de ces situations traumatiques s’enkystent dans le psychisme et font retour, de manière hallucinatoire, dans le transfert, à la recherche d’un autre-semblable capable de leur donner une première forme affective. C’est uniquement grâce à un dur travail d’élaboration contre- transférentielle – illustré ici à travers plusieurs cas d’enfants et d’adolescents psychotiques – que l’analyste arrive parfois à accueillir et à transformer ce transfert du négatif, en accompagnant ainsi ses patients sur le chemin ardu qui mène à la symbolisation (primaire) et à la constitution d’une aire transitionnelle où le je(u) peut enfin advenir. / From the birth of psychoanalysis the conceptualization of the hallucinatory is intimately intertwined with that of the unconscious functioning. In the first topic, the model of the hallucinatory realization of desire explains the baby’s mental functioning, i.e., primal hallucination, the functioning of dreams and neurotic patients in the transference. However, Freud suggests an alternative conceptualization in Constructions in Analysis. Through the hallucinatory, unsymbolized nuclei of historical truth may be re-presented in the treatment. Drawing on Winnicott’s, Green's and Roussillon’s contributions, the Author develops the Freudian heritage and suggests a model in which the intrapsychic and intersubjective dimensions are integrated. The Author puts forward and discusses the existence of a hallucinatory background of the psychism, ruled by the repetition compulsion, that re-activates the psychic inscriptions of early relational experiences. When the primal encounter with the object has failed, traces of these traumatic experiences remain inscribed in the psychism and can be hallucinatory re- activated in the transference in the desperate attempt to find a first representation. Drawing on the case material of psychotic children and adolescents, the Author analyses the complex working through of the countertransference in order to contain this transference of the negative to accompany patients in their arduous way towards (primary) symbolization and the construction of a transitional space of playing.

Security assurance in a computer system can be viewed as distinguishing between self and non-self. Artificial Immune Systems (AIS) are a class of machine learning (ML) techniques inspired by the behavior of innate biological immune systems, which have evolved to accurately classify self-behavior from non-self-behavior. This work aims to leverage AIS-based ML techniques for identifying certain behavioral traits in high level hardware descriptions, including unsafe or undesirable behaviors, whether such behavior exists due to human error during development or due to intentional, malicious circuit modifications, known as hardware Trojans, without the need fora golden reference model. We explore the use of Negative Selection and Clonal Selection Algorithms, which have historically been applied to malware detection on software binaries, to detect potentially unsafe or malicious behavior in hardware. We present a software tool which analyzes Trojan-inserted benchmarks, extracts their control and data-flow graphs (CDFGs), and uses this to train an AIS behavior model, against which new hardware descriptions may be tested.

1 ABSTRACT The presented dissertation deals with prognostic factors influencing a favorable postoperative outcome in patients undergoing surgical treatment of epilepsy and the possibilities of improving the methods used in the localization of epileptogenic lesions. This work is based on the results of four published studies. The first study evaluated the factors influencing the long-term outcomes of epilepsy surgery in MRI-negative (nonlesional) extratemporal lobe epilepsy (nETLE). The aim of the study was to evaluate the benefit of non-invasive diagnostic tests and their relationship with a favorable surgical outcome in a group nETLE patients. Univariate analysis showed that localized interictal epileptiform discharges (IEDs) on the scalp EEG were associated with a favorable surgical outcome. Diagnostic difficulty in this group of patients is highlighted by the fact that, although 9 of 24 patients undergoing surgery had a favorable outcome, and only nine of 85 patients with nETLE achieved such a favorable outcome. The second work evaluated the benefit of SPECT (Single Photon Emission Tomography) statistical processing over traditional subtraction methods in patients with MRI-negative temporal lobe epilepsy (nTLE) and MRI-negative extratemporal epilepsy (nETLE). 49 consecutive patients who underwent...