Thèse ou mémoire avec insertion d'articles. / La maladie de Parkinson (MP) est une maladie neurodégénérative reliée à l'âge qui est caractérisée par une perte des neurones dopaminergiques dans la substance noire pars compacta (SNpc). Bien que la majorité des cas soient idiopathiques, des mutations génétiques peuvent contribuer à l'étiologie d'une forme familiale de la MP, notamment des mutations du gène *SNCA* codant pour la protéine α-synucléine (αsyn) et dans le gène *PARK2* codant pour la protéine parkine. Les corps de Lewy (CL) dans la SN sont un critère diagnostique de la MP. Ces CL sont composés d'αsyn agrégé, où une phosphorylation en sérine 129 est considérée comme étant la modification post-traductionnelle la plus prédominante. La plupart des mutations dans *PARK2* causent une perte d'activité de parkine, ce qui entraîne une dysfonction mitochondriale et un stress oxydatif, menant ainsi à une dégénérescence des neurones dopaminergiques. Cependant, l'étendue des protéinopathies αsyn et parkine reste mal caractérisée dans la SN chez les patients atteints de la MP. Mon projet de maîtrise visait donc à déterminer la teneur, la solubilité relative et le statut de phosphorylation de ces deux protéines dans des homogénats générés à partir de la SN d'une cohorte de donneurs des cliniques des troubles du mouvement de Saskatoon afin de pouvoir examiner leur potentielle implication dans la pathologie de la MP. En plus de quantifier les niveaux de catécholamines, plusieurs données cliniques sur les sujets de l'étude ont été recueillies afin de pouvoir être en mesure d'investiguer la relation entre les caractéristiques cliniques et les deux protéines. Ainsi, cette étude a permis d'établir une association de la conversion de parkine en une forme agrégée et de l'augmentation d'αsyn phosphorylé insolubles dans la SN avec la MP idiopathique, ce qui met en lumière leur implication dans la dégénérescence. / Parkinson's disease (PD) is an age-related neurodegenerative disease characterized by a loss of dopaminergic neurones in the substantia nigra pars compacta (SNpc). While the majority of cases are idiopathic, genetic mutations can contribute to the etiology of a familial form of PD, including mutations in the *SNCA* gene encoding the protein α-synuclein (αsyn) and in the *PARK2* gene encoding the parkin (*PRKN*) protein. Lewy bodies (LB) in the SN is a diagnostic criterion for PD. These LB are composed of aggregated αsyn, where the phosphorylation at serine 129 is considered to be the most predominant post-translational modification. Most *PARK2* mutations cause a loss of parkin activity, which leads to mitochondrial dysfunction and oxidative stress, thus leading to degeneration of dopaminergic neurons. However, the extent of αsyn and parkin proteinopathies remains poorly characterized in the SN of PD patients. My master's project was therefore focused on determining the content, relative solubility and phosphorylation status of these two proteins in homogenates generated from the SN of a cohort of donors from the Movement disorder clinics in Saskatoon in order to be able to examine their potential involvement in the PD pathology. In addition of quantifying the catecholamines levels, several clinical data on subjects of the study were collected in order to be able to investigate the relationship between the clinical characteristics and the two proteins. Thus, this study established an association of parkin conversion to an aggregated form and increased phosphorylated αsyn in the insoluble SN with idiopathic PD, providing new insights on their involvement in degeneration.

Text in Afrikaans / Die studie het ten doel om 'n moontlike verband tussen lokus van kontrole jeens skoolwerk en depressie by die adolessent te identifiseer. Die literatuurstudie ondersoek lokus van kontrole - as aspek van verantwoordelikheid - en depressie, sowel as die ontwikkeling van die adolessent. Uit die literatuurstudie ontstaan die gevoel dat sodanige verband wel bestaan. 'n Gerieflikheidsteekproef - bestaande uit graad 11 leerders - is vir die navorsing gebruik. Die deelnemers vul 'n biografiese vraelys in, sowel as Afrikaanse weergawes van Crandall se Intellectual Achievement Responsibility Questionnaire en die Beck Depression Inventory. Die resultate van die biografiese vraelys, lokus van kontrole vraelys en depressie opname word individueel uiteengesit voordat daar 'n ondersoek gedoen word na moontlike samevallende verskille of korrelasies tussen lokus van kontrole tellings en depressie tellings. weergegee. Gelyktydige voorkoms word ook as persentasies Geen statisties beduidende korrelasies tussen depressie en lokus van kontrole jeens skoolwerk is gevind nie, wat moontlik toegeskryf kan word aan die aard van die steekproef. Verdere navorsing word aanbeveel. / The aim of the study was the identification of a possible relation between locus of control towards schoolwork and depression in adolescence. Locus of control - as an aspect of responsibility - and depression, as well as the development of the adolescent are examined in a literature study. As a result of this the feeling that a relationship between the named variables do exist is expressed. A convencience sample- consisting of grade 11 learners - is used in the research. The participants complete a biographic questionnaire, as well as Afrikaans translations of Crandall's Intellectual Achievement Responsibility Questionnaire and the Beck Depression Inventory. The result of the biographic questionnaire, the responsibility questionnaire and the depression inventory are reported on their own before an investigation is done regarding possible simultaneous differences or correlations between locus of control values and depression values. Percentages are used for the report of simultaneous values. No statistical meaningful differences or correlations were found, which might be ascribed to the nature of the sample. Further research is recommended. / Psychology of Education / M. Ed. (Voorligting)

No description available.

This cross-cultural study investigates the structural and cultural differences and similarities evident in 13 Mandarin (TM) and 17 English language narratives (TEFL) produced by Taiwanese university EFL students and 17 narratives (BE) produced by British university students. This study also explores how the Taiwanese L2 learners’ identities might affect their use of L2 discourse norms within their narratives. The findings show that within the three sets of narratives, past experiences, in general, are recounted in chronological order and the organisation of narratives follows the sequential order defined by Labov (1972). In terms of orientation, there is some cultural variance. The TM and TEFL narratives underscore the importance of family values in Taiwanese society and underline the role of teachers in these students’ worlds. However, the data shows some variance with Labov’s (1972) results in terms of the relationship between complicating action, resolution and evaluation. In terms of external evaluation, the British narrators use much more evaluation in directly addressing their listeners. In terms of internal evaluation, there is significant variance within the three sets of narratives i.e. stress usage, adverb usage, and repetition. The findings suggest that there is no major difference in tellership and tellability in the three sets of narratives. In terms of learner identity, although some Taiwanese EFL students demonstrate high levels of integrative motivation, they have difficulty using L2 discourse norms in their narratives. This is evidenced by their anxiety in relation to their locus of control. It is also manifest that their learner identities have changed over a period of time and were constructed in various sites of struggle, and by relations of power, in which they assumed different subject positions.

Entrepreneurship has been referred to as an economical model for many years; however, the study of entrepreneurship from a psychological perspective is fairly young. Recent literature has focused largely on analyzing the personality characteristics of entrepreneurs and comparing them to wage or salary employed workers. Understanding the personality characteristics of entrepreneurs is vitally important in understanding entrepreneurship, and therefore, the economy as a whole. This study utilizes concepts from past literature and findings from empirical studies in order to assess the personality characteristics associated with successful entrepreneurship. Ultimately, the characteristics; achievement motivation, locus of control, innovation, risk tendencies, and tenacity are analyzed and depicted as the five most important personality characteristics for successful entrepreneurs.

Acute and chronic methylphenidate (MPD) administration was recorded simultaneously in freely moving adolescent rats previously implanted with permanent semi-microelectrodes using telemetric wireless technology for the rat's locomotor activity and for the locus coeruleus (LC) neuronal activity. The evaluation of neuronal events was separated based on the rat's behavioral response to chronic MPD exposure, with rats eliciting behavioral sensitization or behavioral tolerance. On experimental day (ED) 1, the locomotor and neuronal activity was recorded after saline (baseline) and MPD (0.6, 2.5, or 10.0 mg/kg) injection (i.p.). The rats were administered daily with a single dose of MPD for five consecutive days (ED2-ED6) to elicit behavioral sensitization or behavioral tolerance. Following three washout days with no drugs, the locomotor and neuronal activity recordings resumed on ED10 post saline and rechallenge MPD administration. The main findings were as follows. The same dose of chronic MPD administration elicited behavioral sensitization in some rats and behavioral tolerance in other rats. A total of 51.5%, 56.6%, and 86.3% of LC units responded significantly to acute 0.6, 2.5, and 10.0 mg/kg MPD respectively. A total of 51.5%, 72.4%, and 82.3% of LC units responded significantly by changing their baseline activity on ED10 compared to that on ED1 in 0.6, 2.5, and 10.0 mg/kg MPD dose groups respectively. A total of 53%, 67.1%, and 90.2% of LC units responded significantly to chronic 0.6, 2.5, and 10.0 mg/kg MPD respectively. The LC neuronal population recording following acute MPD on ED1 and rechallenge MPD on ED10 from the rats eliciting behavioral sensitization was significantly different from the neuronal population recorded from the rats eliciting behavioral tolerance. Overall, these findings show that the same dose of chronic MPD can elicit behavioral sensitization or behavioral tolerance. We were able to verify our hypothesis that the LC units recorded from the rats eliciting behavioral sensitization responded significantly different to MPD from the rats eliciting behavioral tolerance. This correlation suggests that LC neuronal activity plays an important role in the expression of behavioral sensitization and behavioral tolerance by chronic MPD exposure.

Studiens syfte var att undersöka om det fanns skillnader i personlighet och val av konfliktstil beroende av vilken placering respondenterna hade i syskonskaran samt om Locus of control skiljde sig mellan olika åldersgrupper. Samband mellan chefers konfliktstil och personlighet undersöktes också. De 103 respondenterna som var mellan 25-75 år, 63% män och 37% kvinnor, besvarade en enkät som bestod av demografiska frågoroch arbetsrelaterade frågor om chefskap. Tre test användes; ett personlighetstest, RottersLocus of Control och Thomas-Kihlman’s konfliktstiltest. Resultatet visade att yngresyskon använde konfliktstilen ”samverkan” i högre utsträckning än äldre syskon. Ålderhade inte något samband med inre Locus of control. Fyra av de fem personlighetsfaktorersamvarierade med fyra av de fem konfliktstilarna.Abstract Purpose of this study was to examine whether there were differences in personality andchoice of conflict style was due to birth order and if the Locus of Control was different among different age groups. Links between managers’ conflict style and personality were also examined. The 103 respondents who were between 25-75 years, 63% men and 37% women, answered a questionnaire consisting of demographic questions and work related questions about leadership. Three tests were used: a personality test, Rotter’s Locus of Control and Thomas-Kihlman’s conflict style-test. The results showed that younger siblings used the conflict style "collaborating" to a greater extent than older siblings. Age was not related to Locus of control. Four personality factors covariedwith four conflict styles.

The ‘synaptic tagging-and-capture’ (STC) theory of cellular memory consolidation holds that memory persistence can be altered by prior or subsequent patterns of neural activity (Redondo & Morris 2011). The aim of this thesis was to develop a realistic model of everyday memory for mice and use the optogenetic toolbox to investigate the neuromodulatory circuitry that modulates persistence of everyday spatial memories. The task involved learning a win-stay rule with the daily goal of finding the location of food in the event arena. Using the developed task, it was confirmed that unrelated novel experiences can facilitate the persistence of spatial memory in a manner sensitive to pharmacological blockade of hippocampal dopamine D1/D5 receptors. Further analysis focused on identifying the specific neuromodulatory systems that mediate this effect. An influential model called the ‘hippocampus- VTA loop’ (Lisman & Grace 2005) points to the critical role of dopaminergic neurons in the ventral tegmental area (VTA), but recent evidence also implicates locus coeruleus (LC) as a potential source of dopamine in the hippocampus (Smith & Greene 2012). In order to identify the dopaminergic structure(s) that may mediate the novelty effect on memory persistence, single unit activity of optogenetically identified catecholaminergic (CAergic) neurons in mouse VTA and LC was recorded in a novelty exploration paradigm. Using tyrosine hydroxylase-Cre knock-in mice and a Cre-dependent adeno-associated viral vectors, CAergic neurons in VTA and LC were selectively tagged with channelrhodopsin-2 (ChR2). Conditional ChR2 expression made it possible to reliably identify CAergic neurons during unit recording sessions in freely moving animals. The main conclusion of the study is that that CAergic neurons in both VTA and LC selectively increase their firing rates in novel environments, relative to both a familiar environment and a home cage baseline. When normalised to their average baseline firing rates, LC neurons are more strongly activated by novelty than VTA neurons. In the final experiment outlined in this thesis, another cohort of Th-Cre mice, in which ChR2 was expressed in CAergic neurons of both VTA and LC using a Cre-dependent adeno-associated virus, was trained on the everyday appetitive spatial memory task. ChR2-mediated photoactivation of CAergic neurons in LC but not in VTA 30 min after encoding, substituting for novelty, was successful in enhancing the persistence of memory. Paradoxically, the effect of optogenetic LC activation was blocked by hippocampal microinfusion of dopamine D1/D5 receptor antagonist but not β-adrenergic receptor antagonist. Results of experiments described in this thesis support the principle of STC theory and collectively indicate that dopamine released from hippocampal terminals of LC neurons mediates the novelty effect on memory persistence. Importantly, they also point to a more general of role of LC in gating of entry to long-term memory.

Made available in DSpace on 2018-08-01T23:31:07Z (GMT). No. of bitstreams: 1 tese_10598_O LUGAR DA CRIANÇA NA PÓLIS GREGA_tese_MARCELO SERUTE.pdf: 1368830 bytes, checksum: 1a5899d33d3ef93129a63a6b68cb1927 (MD5) Previous issue date: 2017-01-26 / Este trabalho faz um estudo teórico do lugar da criança na pólis, destacando as relações e os processos originados em um contexto específico, que procura encontrar o sentido histórico e filosófico existente nos séculos IV e III a.C. Utiliza uma genealogia para estudar o cenário do reconhecimento político dos gregos. O foco encontra-se nas práticas discursivas que transitam no idealismo e na representação da pólis, cuja problemática inspira-se no referencial socrático, ou seja, compreender o porquê da aparente ausência do reconhecimento público da criança na pólis. Para desvendar essa questão utiliza o estilo vivencial de Sócrates, e mais especificamente a categorização socrática da doxa, ao estudar a opinião como potencialidade e racionalidade da criança. A disposição socrática ocorre como um estranhamento à política instituída pela pólis e se estabelece à sua margem, gerando tensão, segundo o critério da opinião. Ao se diferenciar dos padrões aplicados no reconhecimento da cidadania da pólis, prefere o argumento à opinião, outra lógica e significado da participação relacional. Sócrates convida seus interlocutores para uma participação reflexiva, relacional e dialógica, porém mais aberta, ou seja, fora do paradigma do enquadramento ideal da polis. Nesse locus, o problema do reconhecimento público da criança se torna complexo devido ao questionamento sobre quais bases e reflexos se sobrepõem ao impacto da afirmação da opinião da criança (e do in-fans). Utiliza práticas discursivas em prol de sua práxis e propõe como nova teoria a possibilidade de instaurar a opinião da criança ao reconhecê-la no espaço público, comum e participativo. Autores secundários e intérpretes do pensamento socrático seguem a lógica pretendida neste trabalho, concentrando-se em duas partes: a primeira é norteada pelos estudos socráticos e pela escolha dos critérios (opinião ou a razão), tanto entre Sócrates e a paideía e a pólis quanto entre Sócrates e os filósofos clássicos Platão e Aristóteles; a segunda tenta restabelecer o mesmo debate da ausência do reconhecimento da criança, mas sob outro referencial, o da modernidade, estudado em seu caráter e especificidade. Assim, este estudo objetivou contribuir para o debate atual ao analisar novos modelos para reconhecer politicamente a criança na sociedade, alicerçado em um mecanismo político regido por outras lógicas.

Den tillgängliga forskningen visar att förekomsten av stress och stressrelaterad ohälsa ökar bland högskolestudenter och påverkar deras studieprestation negativt. Syftet med denna studie var att öka förståelse för studierelaterad stress genom att lyssna på och analysera studenters subjektiva upplevelser och tankar kring studierelaterad stress samt hur de beskriver att de påverkas av och hanterar denna stress. En kvalitativ forskningsmetod valdes i form av semistrukturerad intervju för att besvara frågeställningar. Åtta studenters intervjuer transkriberades och analyserades därefter med tematisk analys.  Resultaten visade på att stress både kunde ses som positiv och negativ. Studenterna beskrev både fysiska, sociala och emotionella konsekvenser. Studien visade på att studenterna hade ett ansvar för att hantera sin stress och möjligheter att förhålla sig och utveckla sin studieteknik men att de också uttryckte en önskan om stöd från högskola. Studien hoppas väcka större intresse för ämnet och utvecklandet av möjligheter för studenter att kunna reducera stress.