Дисертації з теми "Identification of action"

Background: Action Identification Theory holds that every action has different 'levels' of meaning. High levels confer greater meaning and are preferentially sought but when the action is interrupted lower level identities with reduced meaning are elicited. The primary aim of this research was to develop a measure of action identification to investigate the hypothesis that interference to activity caused by chronic pain 'down regulates' levels of action identification thus effectively draining meaning from life. An additional aim was to investigate other factors which influence action identification in chronic pain. Methods: A measure of action identification for pain (AIP) was developed. The AIP was psychometrically evaluated in samples of students. It was administered to 47 chronic pain patients using a forced choice card-sort method. The chronic pain sample also completed the Meaningful Life Measure and measures of pain intensity, pain interference, depression, withdrawal from activity, acceptance and optimism. Results: The AIP demonstrated satisfactory internal consistency and test-retest reliability over 2 to 3 weeks. Data on the inter-correlations between variables are reported. Pain interference negatively correlated with meaning in life and action identification level positively correlated with meaning in life. Multiple regression analyses found that depression and negative mood, acceptance and optimism significantly contributed to variance in meaning in life. Interference and action identification did not. Possible explanations for the results are discussed. Conclusions: The AIP is a promising measure of action identification. Further work is necessary to overcome methodological limitations of the current research to reliably understand the process of action identification in chronic pain. Interventions aimed at increasing acceptance of pain and training optimism may help increase perceived meaning in life in chronic pain.

Human gait identification has become an active area of research due to increased security requirements. Human gait identification is a potential new tool for identifying individuals beyond traditional methods. The emergence of motion capture techniques provided a chance of high accuracy in identification because completely recorded gait information can be recorded compared with security cameras. The aim of this research was to build a practical method of gait identification and investigate the individual characteristics of gait. For this purpose, a gait identification approach was proposed, identification results were compared by different methods, and several studies about the individual characteristics of gait were performed. This research included the following: (1) a novel, effective set of gait features were proposed; (2) gait signatures were extracted by three different methods: statistical method, principal component analysis, and Fourier expansion method; (3) gait identification results were compared by these different methods; (4) two indicators were proposed to evaluate gait features for identification; (5) novel and clear definitions of gait phases and gait cycle were proposed; (6) gait features were investigated by gait phases; (7) principal component analysis and the fixing root method were used to elucidate which features were used to represent gait and why; (8) gait similarity was investigated; (9) gait attractiveness was investigated. This research proposed an efficient framework for identifying individuals from gait via a novel feature set based on 3D motion capture data. A novel evaluating method of gait signatures for identification was proposed. Three different gait signature extraction methods were applied and compared. The average identification rate was over 93%, with the best result close to 100%. This research also proposed a novel dividing method of gait phases, and the different appearances of gait features in eight gait phases were investigated. This research identified the similarities and asymmetric appearances between left body movement and right body movement in gait based on the proposed gait phase dividing method. This research also initiated an analysing method for gait features extraction by the fixing root method. A prediction model of gait attractiveness was built with reasonable accuracy by principal component analysis and linear regression of natural logarithm of parameters. A systematic relationship was observed between the motions of individual markers and the attractiveness ratings. The lower legs and feet were extracted as features of attractiveness by the fixing root method. As an extension of gait research, human seated motion was also investigated.

My research work has been focused on the design, synthesis, and evaluation of new antitumor agents with particular attention to their potential multi-target activity. Tumor is a multifactorial disease characterised by inflammation and hypoxic environment and both these conditions lead to an altered extracellular pH that favour cancer invasion of adjacent tissues. Tumor cells modify their energy metabolic activity to have advantages for the tumorigenesis. A promising approach to obtain anticancer agents could be represented by the identification of new small molecules capable to inhibit more than one enzyme involved in in tumoral growth. Between these enzymes, Cyclooxygenase, Carbonic Anhydrase and Kinase are attractive from the poli-pharmacological point of view. Indeed, both the design of isozyme selective COX and CA inhibitors, and the design of dual Abl/c-Src Kinase inhibitors are promising approaches to the identification of new anti-cancer agents. Different libraries of coumarin and their psoralen analogues EMAC10155, EMAC10156, EMAC10157, EMAC10158, EMAC10159, EMAC10160, EMAC10161 and EMAC10162 have been designed and synthesised with the purpose to further explore the influences of structural modifications on the coumarin and the psoralen core on the activity and selectivity towards CA I, II, IX and XII. None of the new compounds exhibited activity towards the off-targets hCA I and II isozymes. Conversely, both coumarin and psoralen derivates were active against the tumour associated isoforms IX and XII. Different series of potential multi-target agents to investigate on the structural requisites for the selective inhibition of tumor overexpressed hCAs and COX-2 enzymes has been synthetized: EMA10190 and EMAC10191. They present a benzene-sulphonamide group, efficient for the inhibition of COX-2 enzyme, and capable to coordinate the hCAs zinc cofactor in the catalytic site. This essential moiety binds a differently substituted central heterocyclic core either through a hydrazine or a thiazole spacer. Substitutions of the phenyl ring bonded to the hydrazine spacer or to the thiazole spacer is determinant to the selectivity toward the CA tumoral isoform, in particular toward the isoform IX. During my stay at the Lead Discovery Siena, I have designed and synthetized new pyrazolo[3,4-d]pyrimidine compounds substituted in position N-1, C-4 and C-6 to investigate on their inhibition potential towards tyrosine kinase Src and for T315I mutant cells. Significantly, all of the compounds of this library were micromolar inhibitors of Abl and c-Src.

The glycerophosphoinositols (GPIs) are ubiquitous, bioactive metabolites that are produced by the phospholipase A2 IVa activity on the membrane phosphoinositides. Glycerophosphoinositol (GroPIns) and glycerophosphoinositol 4-phosphate (GroPIns4P) are the most active and well studied of the GPIs. When added exogenously, the GPls can enter cells and have multiple effects, such as modulation of actin cytoskeleton organisation in fibroblasts and reduction of the invasive potential of metastatic cells. To gain insights into the molecular mechanisms of the effects of the GPIs, I set out to identify their protein targets. Therefore, a proteomic approach based on high- throughput differential-LC-MS/MS analysis was used with the modified GPIs: with a biotin moiety bound to their glycerol backbone. The targets identified include proteins involved in cell signalling, cytoskeleton organisation, protein folding and metabolic processes. Among these, I focussed my attention on Src-homology phosphatase-l (Shpl), a well-known regulator of Src activation, as it might be related to the reported signalling pathway leading to GroPlns4P-mediated modulation of the actin cytoskeleton, which involves Src. Based on biochemical data, I provide evidence of a direct interaction between Shp 1 and both GroPIns4P .and GroPIns. During my project, Shpl was studied in the context of GroPIns4P-induced membrane ruffle formation in NIH 3T3 fibroblasts, where inhibition of enzymatic activity of Shp 1 completely abolished GroPIns4P-mediated reorganisation of the actin cytoskeleton. In addition, I have also shown that GroPIns4P treatment results in the dephosphorylation of the inhibitory tyrosine residue of Src, as a consequence of increased binding between Shp 1 and Src. A role for Shp 1 is also demonstrated in GroPIns-mediated inhibition of tumour cell invasion. In A375MM melanoma cells, GroPIns treatment results in inhibition of extracellular matrix degradation, and this activity is suppressed when the inactive mutant form of Shp 1 is expressed, while it is essentially unaffected by expression of the native enzyme. In agreement with these results, a lack of effect of GroPIns was observed also in Shpl knock-down cells. In conclusion, my PhD project has led to the definition of Shpl as the first direct GPI target that has been identified to date, and it reveals a positive role for Shpl in the mechanisms of action of both GroPIns4 P and GroPIns.

Poverty stricken areas of the world are affected by Neglected Tropical Diseases, with an estimated 1 billion sufferers. As well as inadequate living conditions and healthcare, there has been very little pharmaceutical incentive to tackle these diseases. As a result, the diseases are still spreading. Drugs available on the market suffer from poor efficacy, high toxicity, increasing resistance and inappropriate dosing for rural treatment. The nature of many NTDs prevents the use of vaccinations. Therefore, more efficacious and safe treatments are sought after. The folate pathway has been extensively studied in a number of organisms, with its essentiality exploited in a number of drugs and drug targets. The same cannot be said for the kinetoplastids. Drug discovery programmes have focused on targeting enzymes of the folate metabolism with very little clinical success. Despite showing significant inhibition of the parasitic enzymes, potency is seen to decrease in cellular and animal models. Understanding how the folate pathway operates in these organisms could provide insight into where and how anti-folate compounds bind. This information could then be used to facilitate better drug treatments for the kinetoplastids. This thesis describes a number of approaches undertaken to better understand folate metabolism in kinetoplastids. Clinical and literature anti-folate compounds were immobilized onto resins, followed by chemical proteomics, utilizing novel techniques (iTRAQ), to allow for target identification. Using competition studies, specific and non-specific targets were identified in parasitic lysate (T. brucei and L. major) for each anti-folate compound. This method was further exploited by creating a folate resin (Folate beads). The resin had the potential to pull down 9 proteins from the “folate-ome”. In future studies, the resin can be used to enrich for the folate proteins in kinetoplastids and related organisms. Alongside the studies of the folate proteins, it was also desired to study proteins involved in the essential pterin pathway. This pathway has not been extensively studied in kintoplastids, with the exception of PTR1 (by-pass protein for DHFR). The failure to synthesise pterin derivatives for bead coupling led to a fragment screening campaign being carried out on QDPR in leishmania major. Working through a triage workflow, two moderately potent fragments were identified, showing inhibition against LmQDPR. Through structure-free optimization strategies, greater than 100 optimized fragments were synthesised in a bid to understand SAR. Although this work remains incomplete, LmQDPR has been successfully crystalized with 23 hit fragments, which are awaiting further biophysical analysis to understand binding.

Ukraine has entered a critical stage of its democratic transition in 2013/14 when the state’s authority was challenged by protests, which led to profound transformations of the political system in a span of four months. The Euromaidan revolution started as a protest against the decision of Ukraine's then government to seek closer ties to Russia rather than sign a negotiated free-trade deal with the European Union. This presented a unique opportunity for social psychological researchers to examine the factors determining both individual-level behavioural intentions to engage in collective action and their intergroup consequences. Focusing on the political events in Ukraine, this dissertation politically contextualizes, historically traces, and empirically investigates the antecedents and consequences of politicized group consciousness and proposes a theoretical framework for the systematic understanding of identity-driven collective behaviour. I develop five interdependent lines of investigation on the social psychology of collective action by answering the following questions: 1) What predicts collective action for social change via aspirational group identity? 2) Under which conditions are people more likely to express their aspirational identities through persuasive rather than confrontational (direct, potentially violent) collective action? 3) What social psychological mechanisms govern a synchronized expression of multiple aspirational identities when social protest is outlawed? 4) What drives people to engage in political solidarity action with another group presumed to be socially and/or politically oppressed (i.e. Crimean Tatars)? 5) How do people explain the legality and morality of their own collective behaviour when evaluating the political outcomes of ingroup activism? The studies presented in this dissertation are based on several large scale surveys, collected in the immediate aftermath of the political events in Ukraine (January – February, 2014; March – April, 2014; and March – April, 2017). The research contributes to an increasing body of research examining how intergroup disputes over realistic and symbolic resources may pertain to intractable conflicts between social groups and discusses the mechanisms behind their resolution. I argue that the Ukrainian case substantiates the claim that socially constructed and instrumentally politicized aspirational group identities play a crucial role in both conflict spiral and conflict prevention.

Objective: The concept of recovery has become an integral part of modern mental health care. Understanding the outcomes and underlying mechanisms of key recovery interventions, such as Wellness Recovery Action Planning (WRAP), is essential in order to expand the theoretical understanding of recovery and inform how to target recovery in treatment. Therefore a systematic review of the literature was conducted to evaluate the mental health outcomes of WRAP for adults. The empirical study then explored three constructs in relation to WRAP and recovery. These were social problem solving, cognitive defusion and social identification. Method: The systematic review of the mental health outcomes of WRAP was conducted by searching four databases, contacting the authors of WRAP research and seeking evaluative information from organisations that deliver WRAP. Fourteen relevant studies met the inclusion criteria. Whereas, the empirical study recruited participants on a trans-diagnostic basis from across Scotland. Using a quantitative cross sectional design, 109 participant's completed 5 self-report questionnaires. These were the Knowledge, Attitudes and Beliefs about WRAP Questionnaire (WRAP beliefs), the Recovery Assessment Scale - Short (RAS-S), the Social Problem Solving Inventory - Revised - Short (SPSI-R-S), the Four Item Measure of Social Identification (FISI) and the Cognitive Fusion Questionnaire (CFQ). Correlation, regression and mediation analysis were used to explore relationships, and in particular, the predictors and mediators of recovery. Results: The systematic review provided strong evidence that WRAP has a significant positive impact on hope and also reduces the symptoms of mental illness. However, whether WRAP improves personal levels of recovery was unclear and a possible risk of disempowerment was found. Promising preliminary mental health outcomes in the areas of confidence in managing mental health, quality of life, service use, self-advocacy and knowledge attitudes and beliefs about recovery were highlighted. Only studies that did not use peer facilitators failed to find significant increases in hope compared to treatment as usual control groups. In the empirical study, the results indicated that all the constructs examined were correlated to recovery. In the regression analysis, WRAP beliefs, social problem solving and cognitive defusion also demonstrated a predictive relationship with recovery. Mediation analysis indicated that, social problem solving mediated two distinct relationships. One between WRAP beliefs and recovery, and another between cognitive defusion and recovery. The social problem solving subscales also showed how the two predictors relate to recovery through social problem solving in different ways. Social identification with the WRAP group did not significantly predict or mediate recovery. Conclusions: The systematic review indicated having peer facilitators delivering WRAP is key to helping participants foster hope and that a further randomised control trial could help clarify if improved personal recovery is an outcome of WRAP. It additionally suggested how the relationship between WRAP beliefs and recovery could be explored, as per the design of the empirical study. Findings from the empirical study implied that improving participants' social problem solving and cognitive defusion should be specifically targeted in WRAP delivery. The studies combined indicate that to achieve the best recovery results interventions, like WRAP, should target inspiring hope through peer support, improving knowledge, attitudes and beliefs about recovery and cognitive defusion from unhelpful thoughts.

To ensure the sustainability of bioethanol production, major attention has been directed to develop feedstocks which provide an alternative to food-crop biomass. Lignocellulosic (LC) biomass, which is chiefly composed of industrial plant residues, is a carbon-rich reservoir that is presently attracting much attention. However LC material is highly recalcitrant to bioprocessing and requires a mixture of physical and enzymatic pretreatment in order to liberate fermentable sugars. Thermostable enzymes are extremely desirable for use in thermophilic fermentations due to their inherent stability. Hemicellulose, a core constituent of LC, requires a cascade of hemicellulases to stimulate the depolymerisation of its xylan backbone. &alpha
-L-arabinofuranosidase (AFase) increases the rate of lignocellulose biodegradation by cleaving arabinofuranosyl residues from xylan thereby increasing the accessibility of other hemicellulases. Twenty thermophilic Actinomycete isolates were screened for AFase activity using pnp-arabinofuranoside as the substrate. Three strains (ORS #1, NDS #4 and WBDS #9) displayed significant AFase activity and were identified as Streptomyces species with 16S rRNA gene sequence analysis. Genomic DNA was isolated from these strains and a cosmid library constructed in the shuttle vector pDF666. Subsequent functional and PCR-based screening revealed no positive clones.

Metagenomics has been successfully used to discover novel enzymes from uncultured microorganisms in the environment. In this study, metagenomic DNA from a Malawian hot spring soil sample was used to construct a fosmid library. This metagenomic library comprised of more than 10000 clones with an average insert size of 30 kb, representing more than 3.0 x 108 bp of metagenomic DNA (equivalent to approximately 100 bacterial genomes). The library was screened for cellulase activity using a Congo red plate assay to detect zones of carboxymethylcellulose hydrolysis. This yielded 15 positive fosmid clones, of which five were further characterised for activity and thermostability using the 3, 5-dinitrosalicylic assay. Two of the five fosmids (XP008C2 and XP026G5) were selected for DNA pyrosequencing. The full sequence of the XP008C2 (29800bp) fosmid insert is presented in this study and genes thereon were chosen for further study.

Un projet visant à identifier des mycoherbicides pour lutter contre les adventices a été initié entre l’UMR Agroécologie de Dijon et la société DE SANGOSSE® (Agen). Trois volets ont structuré ce projet à l’issue d’une collecte de prélèvement de 475 plantes représentatives de 23 espèces d’adventices symptomatiques et asymptomatiques en Bourgogne et en Beauce. Le 1er volet reposait sur une approche de type metabarcoding (technologie Illumina), pour évaluer et comparer la diversité des communautés fongiques endophytes des plantes symptomatiques et asymptomatiques. 542 genres fongiques ont ainsi été identifiés. Des taxons associés aux plantes symptomatiques ont été identifiés. Parmi ceux-ci, certains sont des pathogènes connus, d’autres non et ils constituent des pistes à exploiter pour la recherche de candidats mycoherbicides. Le deuxième volet repose sur une approche conventionnelle de microbiologie et pathologie. Une collection de 194 champignons associés aux symptômes des adventices a été constituée. La pathogénicité de ces isolats a été testée grâce à une série de screenings de plus en plus sélectifs qui ont abouti à la sélection de cinq souches, identifiées par séquençage de l’ITS ou d’autres marqueurs taxonomiques. Une souche appartient à l’espèce Boeremia exigua var exigua, une autre à l’espèce Alternaria alternata, deux appartiennent à l’espèce A. penicillata et la dernière au genre Alternaria. Le troisième volet visait à identifier le mode d’action d’une souche par une double approche, métabolomique et microscopique. La souche de B. exigua var exigua secrète des métabolites phytotoxiques mais également infeste et semble détruire les tissus végétaux sous-épidermique de la plante hôte.Ce projet exploratoire a fourni des pistes de taxons fongiques associés à des symptômes observés sur adventices en analysant la diversité par une approche moléculaire et a fourni des souches fongiques, mycoherbicides potentiels, par une approche microbiologique dont on voit bien qu’elle reste une méthode incontournable, malgré ses limites, pour obtenir des candidats fongiques à action herbicide
A project aiming at identifying mycoherbicides to control weeds has been initiated between the UMR Agroécologie (Dijon) and the company DE SANGOSSE® (Agen, France). Three axes structured this project after a sampling collection of 475 plants representative of 23 species of symptomatic and asymptomatic weeds was carried out in Burgundy and Beauce. The first part was based on a metabarcoding approach (Illumina technology), to evaluate end compare the diversity of endophytic fungi communities of symptomatic and asymptomatic weeds. 542 fungal genera have been identified. Taxa associated with symptomatic plants have been identified. Of these, some are known pathogens, others are not, and both constitute avenues to exploit for the research of mycoherbicide candidates. The second axe is based on a conventional approach to microbiology and pathology. A collection of 194 fungi associated with weed symptoms was established. The pathogenicity of these isolates was tested through a series of increasingly selective screenings that resulted in the selection of five strains that were identified by sequencing of ITS or other taxonomic markers. One strain belongs to the species Boeremia exigua var exigua, another species Alternaria alternata, two belong to the species A. penicillata and the last to the genus Alternaria. The third axe aimed at identifying the mode of action of a strain by a dual metabolomics and microscopic approach. The strain of B. exigua var exigua produced phytotoxic secondary metabolites but also infested and apparently destroyed the sub-epidermal plant tissues of the host plant.This exploratory project provided tracks to exploit fungal taxa associated with observed weeds symptoms, by analyzing the diversity, by a molecular approach and provided fungal strains, potential mycoherbicides by a conventional microbiological approach that we can see it remains an unavoidable method, despite its limitations, to obtain fungal candidates with herbicidal action

Availability of genome sequences for numerous bacterial species comprising of different bacterial strains allows elucidation of species and strain specific adaptations that facilitate their survival in widely fluctuating micro-environments and enhance their pathogenic potential. Different bacterial species use different strategies in their pathogenesis and the pathogenic potential of a bacterial species is dependent on its genomic complement of virulence factors. A bacterial virulence factor, within the context of this study, is defined as any endogenous protein product encoded by a gene that aids in the adhesion, invasion, colonization, persistence and pathogenesis of a bacterium within a host. Anecdotal evidence suggests that bacterial virulence genes are undergoing diversifying evolution to counteract the rapid adaptability of its host&rsquo
s immune defences. Genome sequences of pathogenic bacterial species and strains provide unique opportunities to study the action of diversifying selection operating on different classes of bacterial genes.

The aim of the research reported in this thesis was to examine the way in which exposure to hostile sexism influences women‟s (competitive) collective action intentions, by investigating the mediating role of emotions and the moderating role of identification in this process. Experiments 1-2 (Chapter 2) examined the effect of hostile sexism on women‟s emotional reactions and readiness to engage in social competition. Results showed that exposure to hostile sexism had a positive indirect effect on social competition intentions through increased anger-frustration, and a negative indirect effect through decreased security-comfort. In an effort to understand why hostile sexism has divergent effects on social competition intentions, Experiment 3 (Chapter 3) tested whether the mediating role of emotion is moderated by identification with different female subtypes. Results showed that high (vs. low) identifiers with traditional women who were exposed to hostile sexism were more likely to experience lower levels of confidence-related emotions, and as a result were less motivated to engage in social competition. Although identification did not moderate the effect of hostile sexism on the experience of anger, increased anger was more likely to lead highly identified traditional women to form increased social competition intentions. Experiments 4-6 (Chapter 4) examined whether the divergent effects of hostile sexism on social competition intentions also apply to women‟s intentions to engage in collective action for parity. Results showed that hostile sexism had a positive indirect effect on collective action for parity intentions through anger, but not a negative indirect effect through confidence-related emotions. Overall, the findings of this thesis reveal important differences in the ways that hostile sexism influences women‟s intentions to compete with men, and highlight the importance of considering the specific content of gender identification, and the significance of identifying the specific goal of collective action when examining women‟s reactions to sexism.

The complexity of multi-cellular organisms demands a dynamic reciprocity between neighboring cells in any given tissue. The disruption in keratinocytes and fibroblasts cross-talk in skin has been linked to an imbalance in extracellular matrix (ECM) expression leading to the onset of fibrosis such as hypertrophic scarring. Our group has recently identified 14-3-3σ or stratifin (SFN) as a potent MMP-1 stimulatory factor in fibroblasts. In this doctoral research project, we hypothesized that SFN can modulate other ECM components and execute its transmembrane signaling through interaction with a receptor on the surface of fibroblasts. Three specific objectives were accomplished in this project. Under objective 1, ECM gene expression profile of fibroblasts treated with SFN or co-cultured with keratinocytes was characterized by an ECM-pathway specific gene array and revealed that SFN upregulates a wider range of MMPs such as MMP-3, 8, 10, and 24 other than MMP-1. As SFN was not responsible for the keratinocyte-mediated decrease in collagen expression, under objective 2 attempts were made to characterize the nature of a collagen inhibitory factor in keratinocyte-conditioned medium (KCM). Analysis of keratinocyte/fibroblast co-culture and KCM revealed a 30-50 kDa keratinocyte-derived collagen inhibitory factor with stable activity at high temperature (56 ºC) and acidic environment (pH=2, 30 min). Under objective 3, SFN’s transmembrane signaling mechanism was investigated by utilizing a combination of receptor ectodomain biotin labeling, serial affinity purification, and MS/MS to identify aminopeptidase N or CD13 (APN) as a potential SFN receptor in fibroblasts. APN/SFN binding was further confirmed by immunoprecipitation, cross-linking, and co-distribution studies. Expression of APN and SFN increased after wound closure in a rabbit ear fibrotic model as well as a longitudinal study in rats. The transient knockdown of APN blocked SFN-mediated p38 MAPK activation and MMP-1 expression. Collectively, the findings presented in this thesis provide further support for the importance of keratinocyte-releasable factors in the regulation of ECM and MMP expression in fibroblasts. We also identify APN as a novel cell surface receptor for SFN. Therefore, our findings may provide additional therapeutic tools for the regulation of MMP expression in dermal fibrosis and chronic wound healing disorders.

Type 2 diabetes (T2D) is one of the fasting growing chronic diseases, caused by insulin resistance and pancreatic β-cell dysfunction. While over thirty medications were approved to treat T2D in the United States, less than one in four patients treated with anti-diabetic drugs achieved the glycemic target. Thus, identifying more effective anti-diabetic drugs is still needed for improving glycemic control in T2D patients. Incretins are gut hormones that possess potent insulinotropic action, which have drawn considerable attention in research and developing treatment strategy for T2D. Specifically, glucagon like peptide 1 (GLP-1), the most important incretin that is secreted from enteroendocrine L-cells in response to food ingestion, plays a vital role in maintaining glycemic homeostasis via potentiating glucose stimulated insulin secretion (GSIS) and promoting pancreatic β-cell proliferation and survival. Therefore, targeting L-cells to induce GLP-1 secretion would be an alternative strategy for treating T2D. The goal of this research was to identify low-cost and safe naturally occurring agents as a primary or adjuvant treatment for T2D. Here, I found that a small molecule, elenolic acid (EA), which was generated in our lab but is also present in mature olive and extra virgin olive oil, dose-dependently stimulated GLP-1 secretion in mouse clonal L-cells and isolated mouse ileum crypts. EA induced a rapid increase in intracellular [Ca2+]i and the production of inositol trisphosphate in L-cells, indicating that EA activates phospholipase C (PLC)-mediated signaling. Consistently, inhibition of (PLC) ablated EA-stimulated increase of [Ca2+]i and GLP-1 secretion in L-cells. In addition, EA-triggered GLP-1 secretion from L-cells was blocked by YM-254890, a Gαq inhibitor. Consistent with our in vitro study, a single dose of EA acutely stimulated GLP-1 secretion in mice, accompanied with an improved oral glucose tolerance. Chronic administration of EA restored the impaired glucose and lipid homeostasis in DIO mice, which may be partially due to promoting GLP-1 secretion and reduced hepatic gluconeogenesis. In addition, EA suppressed appetite, reduced food intake and gastric emptying rate, as well as promoted weight loss in obese mice, demonstrating that it is also an anti-obesity agent. Further, EA treatment reduced lipid absorption, and promoted hepatic fatty acid oxidation, and reversed abnormal plasma lipid profiles in DIO mice. Consistently, EA exerted potent anti-diabetic action in db/db mice, and its blood glucose-lowering effect is comparable with that of liraglutide in blood glycemic control but is better than that of metformin in this overt diabetic model. Collectively, I have identified for the first time, as to the best of our knowledge, that EA could be a dual-action compound that exerts anti-diabetic effects via activation of the GLP-1 mediated metabolic pathway and suppression of hepatic gluconeogenesis, leading to effective control on food intake, body weight gain, and glycemia in T2D mice.
Doctor of Philosophy
Type 2 diabetes (T2D) is one of the fasting growing chronic diseases, which results from insulin resistance and pancreatic β-cell dysfunction. Even though there have been over thirty drugs approved to treat T2D in the United States, less than 25% of patients treated with anti-diabetic drugs achieved the glycemic target. Thus, more effective anti-diabetic drugs are still needed for improving glycemic control in patients with T2D. Incretins are a group of gut hormones and responsible for over 50% postprandial insulin secretion in humans, which have drawn considerable attention in research and developing a treatment strategy for T2D. Specifically, glucagon-like peptide 1 (GLP-1), the most important incretin that is secreted from enteroendocrine L-cells in response to food ingestion, plays a vital role in controlling blood glucose via potentiating glucose-stimulated insulin secretion (GSIS) and promoting pancreatic β-cell proliferation and survival. Therefore, targeting L-cells to induce GLP-1 secretion would be an alternative strategy for treating T2D. The goal of this research was to identify low-cost and safe naturally occurring agents as a primary or adjuvant treatment for T2D. Here, I found that a small molecule, elenolic acid (EA), which was synthesized in our lab but is also present in mature olive and extra virgin olive oil, dose-dependently stimulated GLP-1 secretion in mouse clonal L-cells and isolated mouse ileum crypts (containing L-cells). Further experiments showed that EA induced a rapid increase in intracellular [Ca2+]i and the production of inositol trisphosphate (IP3) in L-cells, indicating that EA activates phospholipase C (PLC)-mediated signaling, as IP3 is a direct product of PLC. Consistently, inhibition of PLC ablated EA-stimulated increase of [Ca2+]i and GLP-1 secretion in L-cells. In addition, EA-triggered GLP-1 secretion from L-cells was blocked by YM-254890, a Gαq inhibitor. In line with the in vitro study, a single dose of EA acutely elevated plasma GLP-1 concentration in mice, accompanied by improved oral glucose tolerance. Chronic administration of EA restored the impaired glucose and lipid homeostasis in diet-induced obese (DIO) mice, which may be partially due to promoting GLP-1 secretion and reduced hepatic gluconeogenesis. In addition, EA suppressed appetite, reduced food intake, and gastric emptying rate, as well as promoted weight loss in the DIO mice, demonstrating that it is also an anti-obesity agent. Further, EA treatment reduced lipid absorption and promoted hepatic fatty acid oxidation, as well as reversed abnormal plasma lipid profiles in the DIO mice. Consistently, EA exerted potent anti-diabetic action in predisposed diabetic mice (db/db), and its blood glucose-lowering effect is comparable with that of liraglutide, a commercial GLP-1 receptor agonist, in blood glycemic control but is better than that of metformin, a widely used first-line anti-diabetic drug, in this overt diabetic model. Collectively, I have identified for the first time, as to the best of our knowledge, that EA could be a dual-action compound that exerts anti-diabetic effects via activation of the GLP-1 mediated metabolic pathway and suppression of hepatic gluconeogenesis, leading to effective control on food intake, body weight gain, and glycemia in T2D mice.

Les membranes de nanofiltration sont caractérisées par leurs propriétés de séparation soit de molécules organique de bas poids moléculaire et des sels, soit des sels de valence différentes. Leur capacité de fractionnement est de plus en plus utilisée dans le traitement de l'eau ou le traitement d'effluents polluants d'origine industriel mais aussi dans la concentration de molécules biologiques à haute valeur ajoutée comme les antibiotiques. L’apparition trop récente de ces membranes n'a pas permis de comprendre les mécanismes impliqués lors de la ségrégation. Nous avons réalisé l'étude des propriétés de séparation de trois membranes de seuil de coupure de 100, 200 et 400 Daltons, dans une large gamme de conditions hydrodynamiques et physico-chimiques. Les résultats nous ont montrés que les molécules sont retenues en deux temps. Les particules de grande taille ou fortement chargées sont retenues à la surface de la membrane par effet tamis ou interaction électrostatiques. Les molécules de petite taille et faiblement chargées pénètrent dans les pores de la membrane. Le transfert de ces molécules dépend alors de la force d'entrainement hydrodynamique et des forces de surface (électrostatique, friction, viscosité, hydratation). Les forces de surface ne sont pas négligeables car la taille des pores est très faible ce qui implique que les molécules sont toujours proche de la paroi. Les résultats expérimentaux ont servi de base à l'élaboration d'un modèle qui prend en compte toute ces hypothèses. Le bilan de force s'exerçant sur les molécules de solvant et de soluté aboutit à une équation différentielle complexe résolue par la méthode de collocation orthogonale. La procédure rédigée en Fortran 77 est implantée sur station Sun. Les résultats obtenus montrent que le modèle décrit correctement les hypothèses émises et les résultats expérimentaux obtenus avec des solutions simples ou binaires

The communication barriers between deaf and hearing society mean that interaction between these communities is kept to a minimum. The South African Sign Language research group, Integration of Signed and Verbal Communication: South African Sign Language Recognition and Animation (SASL), at the University of the Western Cape aims to create technologies to bridge the communication gap. In this thesis we address the subject of whole hand gesture recognition. We demonstrate a method to identify South African Sign Language classifiers using an eigenvector ap- proach. The classifiers researched within this thesis are based on those outlined by the Thibologa Sign Language Institute for SASL. Gesture recognition is achieved in real- time. Utilising a pre-processing method for image registration we are able to increase the recognition rates for the eigenvector approach.

The aim of the present study was to evaluate the power of discrimination and genetic (diversity) parameters in the Y chromosome extended haploytpe markers in populations of Tanzania for forensic and populations studies. Eleven Y chromosome extended haplotype markers were selected for this study, these includes Minimal haplotypes markers i.e. DYS19, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS389I/II and two additional markers DYS438 and DYS439. Six populations of Tanzania were investigated under this study. These populations were selected based on the language family categories
Niger Congo (Kuria and Sukuma), Nilo Saharan (Luo and Maasai) and Afro Asiatic (Iraqw and Alagwa).

This thesis consists of three main parts. The first part of the master thesis looks at the identification of thruster dynamics and low speed ship dynamics. The relevant parameters identified are time constants and time delays in the system. Simple step tests are used for the identification. Different models for identification are suggested, both for uncoupled surge, sway, and yaw dynamics. Other test results, such as agility plots, DP 4 corner tests, and pure DP tests (stationkeeping) are reported. All the results are to be compared to similar tests performed after R/V Gunnerus has a retrofit of the thruster system.The second part discusses another problem, and that is the topic of numerically estimat- ing the body frame position of the GNSS and MRU sensors. For the GNSS position an Luenberger observer design and an adaptive scheme are proposed and analyzed. The es- timation designs are tested using numerical simulations and experimental data from the Gunnerus sea trials. A similar Luenberger observer is proposed for the MRU positions, and experimental data from the sea trials are used to test the observer.The third part discusses a hybrid augmentation of integral action. The motivation is a DP system, where typically the integral action is tuned very low to avoid oscillations due to the integral action. When there is a sudden load change, such as a ice load that hits the vessel, or if a mooring wire snaps, then a hybrid update augmentation could be useful, to speed up the convergence of the integral action. The update law is a linear update law based on the error in the states (the velocity for the DP system). The augmentation can significantly improve performance, especially for very large disturbance changes.

Cardiovascular disease (CVD) is the leading cause of death in the United States. Oxidative stress plays an important role in the pathogenesis of CVD. Heart failure is the end point of many forms of CVD. The purpose of this study is to identify novel cardiac specific indicators of oxidative injury useful for early and convenient diagnosis of heart failure.To determine the most suitable method for identification of non-invasive oxidative injury indicators in general, human diploid fibroblasts (HDFs) were treated with H2O2 for collection of mRNA, cell lysates and conditioned media to perform cDNA microarray and LC-MS/MS based Multidimensional Protein Identification Technology (MudPIT) analyses. Electron Spray Ionization (ESI)-LC-MS/MS analysis of the conditioned media led to the finding of IGFBP-6 as a non-invasive biomarker of cell oxidative injuy in vitro and in vivo. The data obtained from this study indicate that proteomic analysis of conditioned media is useful to identify non-invasive biomarkers valuable for diagnosis or management of diseases.Cardiomyocyts (CMCs) and Cardiac fibroblasts (CFs) in culture were used to identify cardiac specific indicators of oxidative stress. Increased level of Cystatin C was detected in the conditioned medium of CMCs due to H2O2 treatment. In vivo models of oxidative stress were used to validate the increase of Cystatin C. Cystatin C levels increased in the plasma of mice with doxorubicin induced cardiomyopathy and coronary artery occlusion induced myocardial infarction (MI). These data indicate that Cystatin C can be a potential indicator of CMC oxidative injury in vitro and in vivo.Cystatin C is a cysteine protease inhibitor. The finding that oxidative stress induces Cystatin C led us to investigate a novel pathway regulating cardiac extracellular matrix (ECM) with CFs in culture, increased levels of ECM protein and decreased levels of Cathepsin B (CTB) protein and activity were detected upon Cystatin C treatment. With coronary artery occlusion induced MI mouse model, increased levels of Cystatin C and ECM protein and decreased levels of CTB protein and activity were detected in the infarcted area of the myocardium. These data indicate that Cystatin C serves as a potential fibrotic factor during myocardial remodeling.

The main objective of this study was to investigate promoter sequences of putative HSR genes for the presence of unique regulatory elements and modules that might be involved in the regulation of HSR. In order to achieve this objective, an in silico promoter analysis strategy was devised, which focused on the identification of promoter sequences and regulatory elements, and modelling of promoter modules by using Genomatix software tools such as MatInspector and ModelInspector. Results showed that two modules (EGRF_SP1F_01 and SP1F_CEBP_01) were conserved in the promoter sequences of three well-known Hsp-genes (Hsp90, Hsp105β and αβ-crystallin). Screening the 60 target gene promoters for the presence of the two modules revealed that 12 genes (20 %) contained both modules. These included Moesin, Proline-4 hydroxylase, Poly(A) binding protein and Formin-binding protein. None of these genes had been previously associated with heat shock response.

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Bachelors
Sciences
Psychology

3ʹ,4ʹ,5ʹ-Trimethoxyflavonol (TMFol), a synthetic analogue of the naturally occurring flavonols quercetin and fisetin, has demonstrated putative anti-cancer activity in the prostate. The mechanisms of action that are engaged are largely unknown. Therefore, the work presented in this thesis investigated the mechanisms used by TMFol to compromise cell proliferation in prostate cell lines 22Rv1, PC-3 and PNT2. Furthermore, it investigated the effect of TMFol on prostate cancer development and progression in two separate transgenic models, PBCre4p53floxRbflox and PBCre4Ptenflox mice. Apoptosis and cell cycle distribution were analysed by flow cytometry, while biochemical assays, Western blots, histological evaluations or qPCR were used to analyse senescence, changes in prostate metabolism and the effect of TMFol on mice. TMFol inhibited cell proliferation in vitro without inducing apoptosis. However the reduction in tumour growth in 22Rv1 xenografts, that were fed a 0.2 % TMFol diet, was associated with a significant increase in cleaved caspase-3 staining, an indicator of apoptosis. There was S phase arrest in the PC-3 and PNT2 cells, while there was an increase in senescence-associated β-galactosidase activity in both 22Rv1 and PC-3 cells. TMFol also caused a significant increase in the protein expression of p21 and p53 in 22Rv1 cells. TMFol significantly inhibited the expression of acetyl-CoA carboxylase at the protein and mRNA levels and the expression and activity of mitochondrial aconitase, which could result in the inhibition of fatty acid synthesis and citrate oxidation, respectively. PBCre4p53floxRbflox and PBCre4Ptenflox mice fed a 0.2 % TMFol diet did not display any evidence of tumours in the prostate, but there was no significant difference in the PIN development between the mice on the control diet and those on the TMFol diet. Taken together, TMFol has the potential to induce cell cycle arrest, apoptosis and senescence and to inhibit fatty acid synthesis and citrate oxidation in prostate cancer cells.

In a world where insecurities, violence and disasters seem to be increasing on a daily basis, compassion, a moral sentiment of co-suffering and motivation to alleviate it, plays an important role, especially in humanitarian action. However, compassion is not a constant feeling, and our emotions and compassion towards tragedies do not always resonate with egalitarian principles. This thesis seeks to explore the potential relationship between field experience, in humanitarian action, and compassion satisfaction and compassion fatigue. Departing from two contrasting hypotheses, grounded in theories of compassion, it investigates the factors, relating to field experience, that affect this moral sentiment, in a single case study of the Network on Humanitarian Action (NOHA). Through a quantitative survey design, combined with semi-structured interviews, the study finds that there exists no isolated correlation between field experience and compassion fatigue or satisfaction. However, the study concludes that compassion is affected by several intervening variables, relating to field experience, which can result in either compassion fatigue or satisfaction, resonating with both hypotheses.

Recent advances in the area of ‘Transformational Government’ position the citizen at the centre of focus. This paradigm shift from a department-centric to a citizen-centric focus requires governments to re-think their approach to service delivery, thereby decreasing costs and increasing citizen satisfaction. The introduction of franchises as a virtual business layer between the departments and their citizens is intended to provide a solution. Franchises are structured to address the needs of citizens independent of internal departmental structures. For delivering services online, governments pursue the development of a One-Stop Portal, which structures information and services through those franchises. Thus, each franchise can be mapped to a specific service bundle, which groups together services that are deemed to be of relevance to a specific citizen need. This study focuses on the development and evaluation of these service bundles. In particular, two research questions guide the line of investigation of this study: Research Question 1): What methods can be used by governments to identify service bundles as part of governmental One-Stop Portals? Research Question 2): How can the quality of service bundles in governmental One-Stop Portals be evaluated? The first research question asks about the identification of suitable service bundle identification methods. A literature review was conducted, to, initially, conceptualise the service bundling task, in general. As a consequence, a 4-layer model of service bundling and a morphological box were created, detailing characteristics that are of relevance when identifying service bundles. Furthermore, a literature review of Decision-Support Systems was conducted to identify approaches of relevance in different bundling scenarios. These initial findings were complemented by targeted studies of multiple leading governments in the e-government domain, as well as with a local expert in the field. Here, the aim was to identify the current status of online service delivery and service bundling in practice. These findings led to the conceptualising of two service bundle identification methods, applicable in the context of Queensland Government: On the one hand, a provider-driven approach, based on service description languages, attributes, and relationships between services was conceptualised. As well, a citizen-driven approach, based on analysing the outcomes from content identification and grouping workshops with citizens, was also conceptualised. Both methods were then applied and evaluated in practice. The conceptualisation of the provider-driven method for service bundling required the initial specification of relevant attributes that could be used to identify similarities between services called relationships; these relationships then formed the basis for the identification of service bundles. This study conceptualised and defined seven relationships, namely ‘Co-location’, ‘Resource’, ‘Co-occurrence’, ‘Event’, ‘Consumer’, ‘Provider’, and ‘Type’. The relationships, and the bundling method itself, were applied and refined as part of six Action Research cycles in collaboration with the Queensland Government. The findings show that attributes and relationships can be used effectively as a means for bundle identification, if distinct decision rules are in place to prescribe how services are to be identified. For the conceptualisation of the citizen-driven method, insights from the case studies led to the decision to involve citizens, through card sorting activities. Based on an initial list of services, relevant for a certain franchise, participating citizens grouped services according to their liking. The card sorting activity, as well as the required analysis and aggregation of the individual card sorting results, was analysed in depth as part of this study. A framework was developed that can be used as a decision-support tool to assist with the decision of what card sorting analysis method should be utilised in a given scenario. The characteristic features associated with card sorting in a government context led to the decision to utilise statistical analysis approaches, such as cluster analysis and factor analysis, to aggregate card sorting results. The second research question asks how the quality of service bundles can be assessed. An extensive literature review was conducted focussing on bundle, portal, and e-service quality. It was found that different studies use different constructs, terminology, and units of analysis, which makes comparing these models a difficult task. As a direct result, a framework was conceptualised, that can be used to position past and future studies in this research domain. Complementing the literature review, interviews conducted as part of the case studies with leaders in e-government, indicated that, typically, satisfaction is evaluated for the overall portal once the portal is online, but quality tests are not conducted during the development phase. Consequently, a research model which appropriately defines perceived service bundle quality would need to be developed from scratch. Based on existing theory, such as Theory of Reasoned Action, Expectation Confirmation Theory, and Theory of Affordances, perceived service bundle quality was defined as an inferential belief. Perceived service bundle quality was positioned within the nomological net of services. Based on the literature analysis on quality, and on the subsequent work of a focus group, the hypothesised antecedents (descriptive beliefs) of the construct and the associated question items were defined and the research model conceptualised. The model was then tested, refined, and finally validated during six Action Research cycles. Results show no significant difference in higher quality or higher satisfaction among users for either the provider-driven method or for the citizen-driven method. The decision on which method to choose, it was found, should be based on contextual factors, such as objectives, resources, and the need for visibility. The constructs of the bundle quality model were examined. While the quality of bundles identified through the citizen-centric approach could be explained through the constructs ‘Navigation’, ‘Ease of Understanding’, and ‘Organisation’, bundles identified through the provider-driven approach could be explained solely through the constructs ‘Navigation’ and ‘Ease of Understanding’. An active labelling style for bundles, as part of the provider-driven Information Architecture, had a larger impact on ‘Quality’ than the topical labelling style used in the citizen-centric Information Architecture. However, ‘Organisation’, reflecting the internal, logical structure of the Information Architecture, was a significant factor impacting on ‘Quality’ only in the citizen-driven Information Architecture. Hence, it was concluded that active labelling can compensate for a lack of logical structure. Further studies are needed to further test this conjecture. Such studies may involve building alternative models and conducting additional empirical research (e.g. use of an active labelling style for the citizen-driven Information Architecture). This thesis contributes to the body of knowledge in several ways. Firstly, it presents an empirically validated model of the factors explaining and predicting a citizen’s perception of service bundle quality. Secondly, it provides two alternative methods that can be used by governments to identify service bundles in structuring the content of a One-Stop Portal. Thirdly, this thesis provides a detailed narrative to suggest how the recent paradigm shift in the public domain, towards a citizen-centric focus, can be pursued by governments; the research methodology followed by this study can serve as an exemplar for governments seeking to achieve a citizen-centric approach to service delivery.

While the many completely sequenced genomes of bacterial pathogens contain all the determinants of the host-pathogen interaction, and also every possible drug target and recombinant vaccine candidate, computational tools for selecting suitable candidates for further experimental analyses are limited to date. The overall objective of my PhD project was to attempt to design reusable systems that employ the two most important features of bacterial evolution, horizontal gene transfer and adaptive mutation, for the identification of potentially novel virulence-associated factors and possible drug targets. In this dissertation, I report the development of two novel technologies that uncover novel virulence-associated factors and mechanisms employed by bacterial pathogens to effectively inhabit the host niche. More importantly, I illustrate that these technologies may present a reliable starting point for the development of screens for novel drug targets and vaccine candidates, significantly reducing the time for the development of novel therapeutic strategies. Our initial analyses of proteins predicted from the preliminary genomic sequences released by the Sanger Center indicated that a significant number appeared to be more similar to eukaryotic proteins than to their bacterial orthologs. In order determine whether acquisition of genetic material from eukaryotes has played a role in the evolution of pathogenic bacteria, we developed a system that detects genes in a bacterial genome that have been acquired by interkingdom horizontal gene transfer.. Initially, 19 eukaryotic genes were identified in the genome of Mycobacterium tuberculosis of which 2 were later found in the genome of Pseudomonas aeruginosa, along with two novel eukaryotic genes.

Surprisingly, six of the M. tuberculosis genes and all four eukaryotic genes in P. aeruginosa may be involved in modulating the host immune response through altering the steroid balance and the production of pro-inflammatory lipids. We also compared the genome of the H37Rv M. tuberculosis strain to that of the CDC- 1551 strain that was sequenced by TIGR and found that the organisms were virtually identical with respect to their gene content, and hypothesized that the differences in virulence may be due to evolved differences in shared genes, rather than the absence/presence of unique genes. Using this observation as rationale, we developed a system that compares the orthologous gene complements of two strains of a bacterial species and mines for genes that have undergone adaptive evolution as a means to identify possibly novel virulence &ndash
associated genes. By applying this system to the genome sequences of two strains of Helicobacter pylori and Neisseria meningitidis, we identified 41 and 44 genes that are under positive selection in these organisms, respectively. As approximately 50% of the genes encode known or potential virulence factors, the remaining genes may also be implicated in virulence or pathoadaptation. Furthermore, 21 H. pylori genes, none of which are classic virulence factors or associated with a pathogenicity island, were tested for a role in colonization by gene knockout experiments. Of these, 61% were found to be either essential, or involved in effective stomach colonization in a mouse infection model. A significant amount of strong circumstantial and empirical evidence is thus presented that finding genes under positive selection is a reliable method of identifying novel virulence-associated genes and promising leads for drug targets.

Many Single Nucleotide Polymorphisms (SNPs) found in coding or regulatory regions within the human genome lead to phenotypic differences that make prediction of physical appearance, based on genetic analysis, potentially useful in forensic investigations. Complex traits such as pigmentation can be predicted from the genome sequence, provided that genes with strong effects on the trait exist and are known. Phenotypic traits may also be associated with variations in gene expression due to the presence of SNPs in promoter regions. In this project, the identification of genes associated with these physical traits of potential forensic relevance have been collated from the literature using a text mining platform and hand curation. The SNPs associated with these genes have been acquired from public SNP repositories such as the International HapMap project, dbSNP and Ensembl. Characterization of different population groups based on the SNPs has been performed and the results and data stored in a MySQL database. This database contains SNP genotyping data with respect to physical phenotypic differences of forensic interest. The potential forensicrelevance of the SNP information contained in this database has been verified through in silico SNP analysis aimed at establishing possible relationships between SNP occurrence and phenotype. The software used for this analysis is MATCH&trade
.

Several of worldwide emerging infections are caused by RNA viruses. For this reason, research in the antiviral chemotherapy field is directed toward the development of compounds that target various steps of the virus life cycle. In this work the antiviral activity of 5-Acetyl-2- Arylbenzimidazoles and 2-[(benzotriazol-1/2 yl)methyl]benzimidazoles has been evaluated against representatives of several virus families, including HCV BVDV, YFV, REO-1, CVB-5, Sb-1 and RSV. Some of the new derivatives turned out to be very interesting for their potency and selectivity against BVDV and HCV (the former), and RSV (the latter), and could be promising candidates for the treatment of the related diseases.

Human perception is one of the most important skills for a mobile robot sharing its workspace with humans. This is not only true for navigation, because people have to be avoided differently than other obstacles, but also because mobile robots must be able to truly interact with humans. In a near future, we can imagine that robots will be more and more present in every house and will perform services useful to the well-being of humans. For this purpose, robust people tracking algorithms must be exploited and person re-identification techniques play an important role for allowing robots to recognize a person after a full occlusion or after long periods of time. Moreover, they must be able to recognize what humans are doing, in order to react accordingly, helping them if needed or also learning from them. This thesis tackles these problems by proposing approaches which combine algorithms based on both RGB and depth information which can be obtained with recently introduced consumer RGB-D sensors. Our key contribution to people detection and tracking research is a depth-clustering method which allows to apply a robust image-based people detector only to a small subset of possible detection windows, thus decreasing the number of false detections while reaching high computational efficiency. We also advance person re-identification research by proposing two techniques exploiting depth-based skeletal tracking algorithms: one is targeted to short-term re-identification and creates a compact, yet discrimative signature of people based on computing features at skeleton keypoints, which are highly repeatable and semantically meaningful; the other extract long-term features, such as 3D shape, to compare people by matching the corresponding 3D point cloud acquired with a RGB-D sensor. In order to account for the fact that people are articulated and not rigid objects, it exploits 3D skeleton information for warping people point clouds to a standard pose, thus making them directly comparable by means of least square fitting. Finally, we describe an extension of flow-based action recognition methods to the RGB-D domain which computes motion over time of persons' 3D points by exploiting joint color and depth information and recognizes human actions by classifying gridded descriptors of 3D flow. A further contribution of this thesis is the creation of a number of new RGB-D datasets which allow to compare different algorithms on data acquired by consumer RGB-D sensors. All these datasets have been publically released in order to foster research in these fields.
Una delle più importanti abilità per un robot mobile che agisce in un ambiente popolato da persone è la capacità di percepire gli esseri umani. Questo non è vero soltanto per la navigazione perché le persone devono essere evitate in maniera diversa dagli altri ostacoli, ma anche perché i robot mobili devono essere in grado di interagire veramente con gli esseri umani. In un prossimo futuro, si può immaginare che i robot saranno sempre più presenti in ogni casa e svolgeranno compiti utili al benessere delle persone. Per questo scopo, è necessario utilizzare robusti algoritmi di tracking e le tecniche di re-identificazione svolgono un ruolo importante per far sì che i robot riconoscano una persona anche dopo un'occlusione totale o dopo lunghi periodi di tempo. Inoltre, essi devono essere in grado di riconoscere le azioni delle persone per reagire in maniera adeguata, aiutandole se necessario o anche apprendendo da loro. Questa tesi affronta queste problematiche proponendo approcci che combinano algoritmi basati su informazioni RGB e di profondità che possono essere ottenute con i sensori RGB-D recentemente introdotti nel mercato. Il nostro contributo chiave alla ricerca sulla rilevazione e il tracking di persone è un clustering basato sull'informazione di profondità che permette di applicare un rilevatore di persone robusto e basato sull'immagine solamente a un ristretto insieme delle possibili finestre di detection, quindi diminuendo il numero di falsi allarmi e raggiungendo un'elevata efficienza computazionale. La ricerca sulla re-identificazione di persone viene avanzata proponendo due tecniche che sfruttano algoritmi di tracking dello scheletro basati sull'informazione di profondità: una è pensata per la re-identificazione a breve termine e crea una firma compatta, ma discriminativa, delle persone calcolando delle feature alle posizioni chiave dello scheletro, che sono altamente ripetibili e semanticamente significative; l'altra estrae feature a lungo termine, come la forma 3D, per confrontare le persone in base alla loro nuvola di punti 3D acquisita con un sensore RGB-D. Per tenere conto del fatto che le persone non sono oggetti rigidi, ma sono articolate, questa tecnica sfrutta l'informazione 3D dello scheletro per ricondurre le nuvole di punti delle persone ad una posa standard che le renda direttamente confrontabili mediante un fitting ai minimi quadrati. Infine, viene descritta un'estensione al dominio RGB-D delle tecniche di riconoscimento di azioni basati sul flusso ottico. Questa estensione calcola il flusso nel tempo dei punti 3D di una persona sfruttando congiuntamente l'informazione di colore e profondità e riconosce le azioni umane classificando descrittori a griglia del flusso 3D. Un ulteriore contributo di questa tesi è la creazione di una serie di dataset RGB-D che permettono di confrontare diversi algoritmi su dati acquisiti con sensori RGB-D di tipo consumer. Tutti questi dataset sono stati rilasciati pubblicamente per favorire la ricerca in questi settori.

The process of cytotoxic T lymphocyte (CTL) killing involves the recognition and destruction of foreign antigens by cytotoxic T cells and is of crucial importance to the defence of the organism against viral infections. Defects in this process can lead to various autoimmune diseases and cancer. The aim of this study was to identify more genes involved in the cell death pathway and to link CTL killing, apoptosis and cancer.

Species of Campylobacter, Arcobacter and Helicobacter have been associated with various diseases in humans and animals
and chickens have been identified as a reservoir of these microorganisms. Two published techniques and a new technique, developed in this dissertation, were evaluated to test its efficiency in removing PCR inhibitors from chicken samples. All of the techniques were based on agarose/DNA slants and were evaluated using multiplex PCR and an Internal Amplification Control. The new technique was found to be most effective and consequently used further in the study. A novel study was done to evaluate the survival of Campylobacter, Arcobacter and Helicobacter strains in chicken blood at -20, 4, 37 and 42º
C as well as at ambient room temperature (±
22º
C). It was found that all strains could survive at all temperatures, albeit at different duration times. Most notably, an A. butzleri strain was able to survive at 4oC for up to 297 days.

Listeria monocytogenes is a Gram-positive bacterium responsible for listeriosis, a food-borne disease, which may result in severe illness and possible death. The importance of L. monocytogenes as a food-borne pathogen has been recognized since the 1980's when a correlation between the cunsumption of contaminated foodstuffs and human listeriosis outbreaks was observed. Listeriosis occurs with the ingestion of contaminated foods. The aim of this study involved developing DNA based methods to aid the food industry for the fast detection of L. monocytogenes in food products. Therefore assays were developed in such a way that they will have potential applications in the food idustry.

Obesity is a globally increasing disease particularly in developing countries and among children. It is mainly caused by intake of diets high in fat and the lack of physical activity. Obesity is a risk factor for diseases such as type II diabetes, high blood pressure, high cholesterol and certain cancers. Prediabetes is a condition where blood glucose levels are above normal but have not 
reached those of diabetes. It is difficult to diagnose, as there are no signs or symptoms. Some type II diabetes patients bear no symptoms at all and the disease is discovered late. Proteomics is a field that can provide opportunities for early diagnosis of diseases through biomarker discovery. The early diagnosis of diabetes can assist in the prevention and treatment of diabetes. Therefore there is a need for the early diagnosis of diabetes. Twenty Wistar rats were used. The rats were initially fed a CHOW diet, which is the standard balanced diet for rats, for 4 weeks. The rats were then divided into 2 groups of 10 where 1 group was fed CHOW and another was fed a high fat (HF) diet in order to induce obesity. The two groups were fed their respective diets for 18 weeks. Rats were weighed. Rats were placed in metabolic chambers and 24 hour urine samples were collected. Ketone levels were measured by Ketostix. Urine proteins were precipitated by acetone, quantified and separated on both the 1D SDS-PAGE and the 2D SDS-PAGE. Protein expression changes between CHOW and HF fed rats were determined and identified using MALDI-TOF mass spectrometry. Protein spots intensities increased and decreased between the CHOW and HF fed rats. Transducin (beta)-like 3 was identified as the only differentially expressed protein, which might serve as a potential biomarker for prediabetes.

Brazil’s vision of race has been changing. In contrast with its former tendency to avoid static racial identifications and discussions of race, the country is pushing toward clearer racial definitions in order to institute racially targeted programs, such as racial quotas for Non-Whites in public universities. Using in-depth interviews from 19 students who entered university through racial quotas, this paper explores how these students envision fixed categories for themselves, how they deal with these categories in different situations, and what they think the implications of these shifts in racial understanding will be. The study shows that the racial categories proposed in legislation often do not represent the way students see themselves; indeed, they may not feel that racial categorization is something natural to their existence before applying for university. Respondents often feel discomfort dealing with the idea of categorization, as well as with the meaning of each category, and as a result they sometimes appropriate and redefine the categories. They speak of being reminded of their racialized bodies when contrasted or compared with others or their environment, and they demonstrate that race is a very flexible concept in their minds, varying in different situations. As well, their perceptions of race implicate ideas about social class and even personal aesthetics that are easily mutable. In trying to come to terms with the idea of race and how to bound it to something they can understand and grasp, students come to dispute the authenticity of racial claims. These disputes over how someone’s race is authentic may provide a space in which new meanings of race and racial categories can be created.
Arts, Faculty of
Sociology, Department of
Graduate

Since the time humans have developed speech, storytelling has been a crucial part of society. Its values lie in the ability to communicate potential dangers about the world to generating laughter and tears as a form of entertainment. A central theme in stories that continues to reoccur over the course of history is the story of the hero. Carl Jung theorizes that the hero is an archetype in the collective unconscious, which explains humans’ innate inclinations towards heroes. Throughout history, the forms of storytelling have evolved due to technological and intellectual advancements. In modern times, film has risen as the leading modality for storytelling. The central theme of heroes continues to reoccur in this modality and is testified by the dominance of action hero movies in the box office. The purpose of this paper is to develop a model that details how to craft a compelling action hero movie based on empirical psychological research. The paper defines a compelling action hero movie as a movie with an action hero protagonist that maximizes narrative transportation, persuasion and enjoyment. By dissecting the construction of the film into its plot, character/diction, theme, melody and spectacle, the paper develops the PCTMS-NTPE Model that maximizes narrative transportation, persuasion and enjoyment in each aforementioned components. The beneficiaries of this paper are filmmakers and individuals who want to understand the inner psychological mechanics of a compelling action hero movie.

Régulièrement, les associations caritatives sollicitent financièrement des millions d’individus pour mener leurs actions sur le terrain. Représentant un enjeu majeur, ces campagnes de communication médiatique ont pour objectif d’appeler aux dons afin de collecter des fonds leur permettant de pérenniser leurs actions et de maintenir une indépendance à la fois financière et politique. Articulant une double méthodologie qualitative et expérimentale et l’aide d’un contexte théorique pluridisciplinaire mobilisant des ressources théoriques issues notamment des modèles psychosociaux de la réception, de la communication persuasive et de la communication engageante, la thèse vise le double objectif de mieux comprendre les processus de production et de réception de la communication d’appel aux dons des associations caritatives. Dans une logique de recherche action et devant l’importance des enjeux humains, nous proposons également des pistes pour contribuer à accroitre l’efficience des dispositifs de communication
Charities regularly solicit millions of individuals financially to carry through their actions on the field. Representing a major stake, these media communication campaigns aim at calling for donations in order to raise funds which enable them to keep up their actions and maintain an independence both financially and politically. However, in literature so far, no research has been carried out about the socio-cognitive processes involved in this type of communication.Structuring a double qualitative and experimental methodology and the help of a theoretical multidisciplinary context calling up the theoretical resources mainly from the psychosocial models of the reception, the persuasive communication and the binding communication, this dissertation targets a double objective, namely a better understanding of the production and of the reception processes involved in the binding communication of charity fundraising campaigns