Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The assessment of oral proficiency forms an important part of learning a second language. However, the manual assessment of oral proficiency is a labour intensive task requiring specific expertise. An automatic assessment system can reduce the cost and workload associated with this task. Although such systems are available, they are typically aimed towards assessing students of American or British English, making them poorly suited for speakers of South African English. Additionally, most research in this field is focussed on the assessment of foreign language students, while we investigate the assessment of second language students. These students can be expected to have more advanced skills in the target language than foreign language speakers. This thesis presents a number of scoring algorithms for the automatic assessment of oral proficiency. Experiments were conducted on a corpus of responses recorded during an automated oral test. These responses were rated for proficiency by a panel of raters based on five different rating scales. Automatic scoring algorithms were subsequently applied to the same utterances and their correlations with the human ratings determined. In contrast to the findings of other researchers, posterior likelihood scores were found to be ineffective as an indicator of proficiency for the corpus used in this study. Four different segmentation based algorithms were shown to be moderately correlated with human ratings, while scores based on the accuracy of a repeated prompt were found to be well correlated with human assessments. Finally, multiple linear regression was used to combine different scoring algorithms to predict human assessments. The correlations between human ratings and these score combinations ranged between 0.52 and 0.90. / AFRIKAANSE OPSOMMING: Die assessering van spraakvaardigheid is ’n belangrike komponent van die aanleer van ’n tweede taal. Die praktiese uitvoer van sodanige assessering is egter ’n arbeids-intensiewe taak wat spesifieke kundigheid vereis. Die gebruik van ’n outomatiese stelsel kan die koste en werkslading verbonde aan die assessering van ’n groot aantal studente drasties verminder. Hoewel sulke stelsels beskikbaar is, is dit tipies gemik op die assessering van studente wat Amerikaanse of Britse Engels wil aanleer, en is dus nie geskik vir sprekers van Suid Afrikaanse Engels nie. Verder is die meerderheid navorsing op hierdie gebied gefokus op die assessering van vreemde-taal sprekers, terwyl hierdie tesis die assessering van tweede-taal sprekers ondersoek. Dit is te wagte dat hierdie sprekers se spraakvaardighede meer gevorderd sal wees as di´e van vreemde-taal sprekers. Hierdie tesis behandel ’n aantal evaluasie-algoritmes vir die outomatiese assessering van spraakvaardighede. Die eksperimente is uitgevoer op ’n stel opnames van studente se antwoorde op ’n outomatiese spraaktoets. ’n Paneel van menslike beoordelaars het hierdie opnames geassesseer deur gebruik te maak van vyf verskillende punteskale. Dieselfde opnames is deur die outomatiese evaluasie-algoritmes verwerk, en die korrelasies tussen die beoordelaars se punte en die outomatiese evaluerings is bepaal. In kontras met die bestaande navorsing, is daar gevind dat posterieure waarskynlikheidsalgoritmes nie ’n goeie aanduiding van spraakvaardighede gee vir ons datastel nie. Vier algoritmes wat van segmentasies gebruik maak, is ook ondersoek. Die evaluerings van hierdie algoritmes het redelike korrelasie getoon met die punte wat deur die beoordelaars toegeken is. Voorts is drie algoritmes ondersoek wat daarop gemik is om die akkuraatheid van herhaalde sinne te bepaal. Die evaluerings van hierdie algoritmes het goed gekorreleer met die punte wat deur die beoordelaars toegeken is. Laastens is liniˆere regressie gebruik om verskillende outomatiese evaluerings te kombineer en sodoende beoordelaars se punte te voorspel. Die korrelasies tussen hierdie kombinasies en die punte wat deur beoordelaars toegeken is, het gewissel tussen 0.52 en 0.90.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

There are differences today amongst psychoanalysts regarding if psychoanalysis should limit itself to being exclusively a hermeneutic discipline or if psychoanalysis should find points of contact with neurobiology. The purpose of this essay is to touch upon the larger issue that creates the different points of view: Can psychoanalysis become enriched by finding points of contact with neurobiology, and should psychoanalysis be regarded as belonging to a broader scientific field than being exclusively a human science? The question at issue is: Can modern neurobiology contribute to a development of the psychoanalytic concepts; compulsion to repeat, transference/countertransference and talking cure? The method used is a literature study. The result shows that: Freud’s theories regarding traumatic compulsion to repeat can be linked with LeDoux’s theory of "emotional memory". Freud’s theory of the death instinct as an explanation to the compulsion to repeat can be replaced by a modern neurobiological theory of "emotional memory". The part of the countertransference that is an emotion transferred from the patient to the analyst can happen with the assistance of mirror neurons through "embodied simulation". This suggests that the phenomenon of the analyst being able to experience the patients emotion in himself does not have to imply that projection or intersubjective pressure have played a part in it. To be able to include this phenomenon in the concepts of transference and countertransference these need to be broadened or revised. It is possible to link and develop Freud’s theory of the talking cure with Deacon’s theory about symbolic communication. The results clinical implications are: Understanding of the traumatic compulsion to repeat as an expression of "emotional memory" demands work with this as an expression of memory processes. Understanding of the transference of emotion in transference/countertransference as possible through reflexive simulation processes, implies that projection or interpersonal pressure should not be preconceived in an emotion transference situation. It also implies that the emotional activation in the analyst should not by necessity be seen as an activation of the analyst’s internal objects together with emotions towards these. Deacon’s theory of symbolic communication implies that the talking cure should be used with awareness of its negative tendencies, visual thinking should not necessarily be considered non-symbolic and focus should be put on multiple ways of communication in the clinical situation.

Visual acuity is reduced when optotypes are viewed in the presence of surrounding contours. This reduction in acuity is known as the crowding effect and is thought to be caused by a varying combination of contour interaction, gaze instability and attention. Traditional studies have used single optotypes surrounded by flanking bars to investigate crowding. Such targets may not realistically replicate the crowding effect inherent in clinical vision charts. The aim of this thesis was to systematically investigate the effect of crowding on visual thresholds in subjects with normal vision and in subjects with amblyopia, using specially designed charts. In the 1st and 2nd experiment, contour interaction was assessed using a high (80 %) and low contrast (5.8%) Sheridan Gardiner repeat letter (SGRL) chart in subjects with normal vision. The effect of contour interaction was investigated by varying the inter-letter separation in the SGRL chart. Significant contour interaction was obtained at the abutting condition for both the contrast conditions. In the 3rd experiment the same protocol was repeated but in amblyopes. Significant contour interaction was obtained at 0.2 letter separation and the abutting condition for both the contrast conditions. The effect of contour interaction appears to be less for low contrast than for high contrast letters in normal, non-amblyopic and amblyopic eyes. Finally, in the 4th experiment a Sheridan Gardiner Complex Interaction (SGCI) chart that requires imposed gaze fixations was constructed to measure visual acuity in normal’s and amblyopes. The effect of any gaze instability on crowding was investigated by comparing SGRL thresholds to SGCI thresholds. The SGCI thresholds were higher than the SGRL thresholds at all the separations measured, suggesting an important effect of gaze instability on crowding. In conclusion, this research has shown that gaze instability is an important component of the crowding effect for letter chart acuity measurements. Visual acuity especially when screening for amblyopia should be measured using a whole optotype chart that requires optotype to optotype fixation.

Background: Rapid repeat pregnancy (RRP), a pregnancy occurring less than 24 months from a prior birth, and unintended pregnancy-related induced abortions can be prevented with family planning. However, few studies have adequately addressed the role of male partners in reproductive decision-making. Objectives: The goal of this research is to understand the interrelationships between couple pregnancy intention, intimate partner violence (IPV), reproductive health and behaviors. Specifically, this project aims to: (1) examine the extent to which couple pregnancy intentions are associated with RRP and (2) induced abortions among women in the U.S., and (3) examine the extent to which IPV around the time of pregnancy is associated with postpartum birth control use by race/ethnicity and receipt of prenatal contraceptive counseling among U.S. women with live births. Methods: This project uses data from the 2006-2010 National Survey on Family Growth (NSFG), and the 2004-2008 national Pregnancy Risk Assessment Monitoring System (PRAMS). RRP and induced abortion of first pregnancy were self-reported in the NSFG. Couple pregnancy intentions were categorized as: both intended (M+P+), both unintended (M-P-), maternal intended and paternal unintended (M+P-), maternal unintended and paternal intended (M-P+). Multiple logistic regression analysis was used to assess the relationships between couple pregnancy intentions and RRP and induced abortion. Data on IPV and postpartum contraceptive use came from PRAMS. Stratified analyses were conducted to assess differences in the association by race/ethnicity and receipt of prenatal contraceptive counseling. Results: Compared to couples where pregnancy was intended by both, those with discordant pregnancy intentions and both unintended pregnancy had greater odds of induced abortion. The odds of RRP was higher for M-P+ couples and lower for M+P- couples. Abused women were significantly less likely to report postpartum contraceptive use. This was particularly true for Hispanic women who reported no prenatal birth control counseling and all other racial/ethnic groups who received birth control counseling. Conclusion: Health providers may need to consider the interpersonal dynamics of couple-based decision-making and behaviors to prevent RRP and induced abortions due to unintended pregnancy. Providers should discuss contraceptive options that are not partner-dependent within the context of abusive relationships.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

TRPA1 is a thermosensitive ion channel from the family of TRP (transient receptor potential) receptors. In primary sensory neurons, TRPA1 is an important transducer of painful stimuli, where it contributes to detection of noxious, irritant and inflammatory compounds of endogenous and exogenous origin. The major activation mode of TRPA1 is covalent modification of N-terminal cysteines or lysines by electrophilic compounds. The potency of the electrophilic agonists is increased by voltage dependency of the TRPA1 channel, which contributes substantially during membrane depolarization. To date, the role of several cysteine residues in the N- terminus has been demonstrated. However, the functional role of six cysteines in the transmembrane domain is still unknown. The first part of the thesis focuses on the functional role of the transmembrane cysteines in the activation of human TRPA1 channel. Our results indicate that these sites do not mediate reactive-electrophile-induced activation but four of the six cysteines substantially contribute to voltage-dependent gating of the channel and two participate in calcium-dependent modulation of TRPA1. In the second part of this thesis we aim to explore the proximity of two specific charged residues, located in the linker between the fourth and the fifth...

Thesis advisor: Charles S. Hoffman / Glucose detection in yeast occurs via a cAMP signaling pathway that is similar to that of other signaling pathways in humans. The presence of glucose in the environment ultimately represses, as a result of cAMP signaling, the transcription of the gene fbp1. Adenylate cyclase is known to convert ATP to cAMP, and is thus a central protein in the propagation of the signal. Mutant forms of the adenylate cyclase gene (git2) have been found by the inability for the organism to repress fbp1 transcription in the presence of glucose. In this study, two questions were under investigation. The first was focused on the ability of the mutations to affect the dimerization of the catalytic domain. The second investigated multiple protein-protein interactions in the leucine rich-repeat (LRR) domain of adenylate cyclase. Both domains contain mutations that confer an activation defect, and they are thus are thought to have a relationship. / Thesis (BS) — Boston College, 2005. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology. / Discipline: College Honors Program.

O objetivo desse estudo foi avaliar se a baixa fertilidade de vacas Holandesas repetidoras de serviço [RS; comparativamente a novilhas (NOV) e vacas próximas ao pico de lactação (PL)] está associada com comprometimento da qualidade oocitária e se esta condição é agravada pelo estresse térmico. Fêmeas das três categorias foram tratadas com o mesmo protocolo de sincronização da emergência de onda folicular. Cinco dias após o início do protocolo, a ovum pick-up (OPU) foi realizada e foram avaliados (Capítulo; Cap. 1) o número de folículos ovarianos, de oócitos totais e viáveis, temperatura retal (TR), temperatura de superfície cutânea (TC) e frequência respiratória (FR). Os oócitos viáveis foram utilizados para a produção in vitro de embriões (Cap. 2) e avaliações biomoleculares (Cap. 3). No Cap. 2, foram avaliados o desenvolvimento embrionário (taxa de clivagem, de blastocisto e de eclosão) e a qualidade dos embriões produzidos (número de células e frequência de núcleos fragmentados). No Cap. 3, realizou-se a extração de RNA e DNA de parte dos oócitos coletados para a quantificação relativa e absoluta de DNA mitocondrial (mtDNA) e a avaliação da expressão de genes relacionados à replicação/transcrição do mtDNA (PPARGC1A, NRF1, POLG, POLG2, TFAM e MT-CO1), à apoptose (BAX, BCL2 e ITM2B) e ao estresse térmico (HSP90AA1 e HSPA1AB). No Cap. 4, a taxa de concepção após IATF foi avaliada em ambas as estações do ano e nas três categorias quando o mesmo protocolo de sincronização para IATF e a mesma partida de sêmen foram utilizados. No Cap. 1, vacas RS e PL aumentaram sua FR e TR no verão em relação ao inverno (P<0,0001), enquanto as NOV mantiveram essas variáveis constantes em ambas as estações. Nas três categorias houve aumento (P<0,0001) da TC no verão, mas esta sempre foi superior (P<0,001) em vacas RS e PL do que nas NOV, independente da estação. O número de folículos e de oócitos totais e viáveis declinou nas RS e PL durante o verão, mantendo-se semelhante em NOV em ambas as estações. No Cap. 2, a taxa de clivagem foi semelhante entre categorias e estações. Já a taxa de blastocisto foi reduzida no verão nas três categorias, sendo essa queda mais acentuada nas RS. A taxa de eclosão e o número de células dos blastocistos foram menores no verão (independente de categoria). Menor número de células foi observado em embriões de RS e PL (independente da estação). Além disso, a porcentagem de núcleos fragmentados foi maior nos blastocistos das RS no verão. No Cap. 3, a expressão de ITM2B e BAX foi maior em RS durante o verão. Ainda, detectaram-se indícios da ativação de mecanismos pró-apoptóticos nos oócitos de RS (maior relação BAX/BCL-2) comparadas a PL e de mecanismos compensatórios da deficiência da função mitocondrial (menor conteúdo de mtDNA e maior expressão de PPARGCC1, NRF1, TFAM, POLG e POLG2) nas RS durante o verão em relação as demais categorias. No Cap. 4, menor taxa de concepção foi observada em RS e durante o verão. Os resultados geram evidências de que o baixo desempenho reprodutivo de vacas RS durante o verão deva estar relacionado ao comprometimento da qualidade de seus oócitos, demonstrado pelo seu reduzido conteúdo de mtDNA e elevada expressão de genes relacionados a replicação/transcrição do mtDNA, apoptose e síntese de chaperonas, culminado em baixa taxa de blastocisto e alta fragmentação nuclear destes. / The aims of the present study were to evaluate whether lower fertility of repeat-breeder (RB) Holstein cows [compared to peak lactation cows (PL) and heifers (H)] is associated with oocyte quality and whether this condition is aggravated by summer heat stress. Females of the three categories were treated with same protocol for synchronization of follicular wave emergence during summer and winter. Five days after the protocol onset, the ovum pick-up (OPU) was performed. The following variables were evaluated in Chapter 1: number of ovarian follicles before OPU, number of total and viable oocytes, rectal temperature (RT), cutaneous temperature (CT) and respiration rate (RR). Viable oocytes were sent forThe aims of the present study were to evaluate whether lower fertility of repeat-breeder (RB) Holstein cows [compared to peak lactation cows (PL) and heifers (H)] is associated with oocyte quality and whether this condition is aggravated by summer heat stress. Females of the three categories were treated with same protocol for synchronization of follicular wave emergence during summer and winter. Five days after the protocol onset, the ovum pick-up (OPU) was performed. The following variables were evaluated in Chapter 1: number of ovarian follicles before OPU, number of total and viable oocytes, rectal temperature (RT), cutaneous temperature (CT) and respiration rate (RR). Viable oocytes were sent for in vitro embryo production (Chapter 2) and bimolecular evaluation (Chapter 3). In Chapter 2, embryo development (rates of cleavage, blastocyst and hatching) and quality (total number of nuclei and frequency of nuclear fragmentation) were assessed. In Chapter 3, part of the oocytes were subjected to DNA and RNA extraction to allow relative and absolute quantification of mitochondrial DNA (mtDNA), and the evaluation of the expression of genes related to mtDNA replication/transcription (PPARGC1A, NRF1, POLG, POLG2, TFAM and MT-CO1), apoptosis (BAX, BCL2 and ITM2B) and heat stress (HSP90AA1 e HSPA1AB). In Chapter 4, RB, PL and H were subjected to same protocol for fixed-time AI using the same batch of semen of a single sire in order to evaluate their P/AI during summer and winter. In Chapter 1, RB and PL had increased (P<0.0001) RR and RT during summer compared to winter; while H maintained similar RR and RT in both seasons. CT was greater (P<0.0001) during summer than winter in all categories, but it was always higher (P<0.001) in RB and PL than H, regardless of season. The numbers of follicles and total and viable oocytes were lower in RB and PL during summer than winter, and maintained stable in H in both seasons. In Chapter 2, cleavage rate was similar among categories and between seasons. However, blastocyst rate was invariably reduced during summer, but more pronouced in RB. Hatching rate and the total number of nuclei were decreased during summer, regardless of category. Lower number of nuclei was observed in RB and PL embryos compared to H, regardless of the season. Furthermore, the percentage of fragmented nuclei was greater in RB blastocysts during the summer. In Chapter 3, expressions of ITM2B and BAX were greater in RB oocytes collected during summer. Also, the activation of pro-apoptotic mechanisms (greater BAX/BCL2 ratio) was suggested in RB heat stressed-oocytes compared with PL. Activation of compensatory mechanisms of deficient mitochondrial function (low number of copies of mtDNA and increased expression of PPARGCC1, NRF1, TFAM, POLG and POLG2) were also observed in RB heat stressed-oocytes compared with PL and H. In Charpter 4, lower P/AI was observed in RB and under summer heat stress. These data provide evidences that the lower reproduction performance observed in RB during heat stress may be due to impaired oocyte quality, as shown by their reduced mtDNA content and upregulation of several genes related to mtDNA replication/transcription, apoptosis and chaperones synthesis, resulting in lower blastocyst rate and higher nuclear fragmentation of embryos.

The goal of this thesis is to propose strategies that profitably stimulate repeat purchase behaviour of Solosso's customers, Solosso being an e-commerce start-up producing custom made dress shirts. In order to accomplish the stated goal, research has been conducted into the existing body of literature about the subject, models for managing customers for value have been presented and applied on Solosso's customer database. Additionally, customer survey has been conducted to better understand customers' behaviour. Based on the applied models and the findings from the survey, the thesis delivers a set of recommendations on how to improve the product, what customers to acquire and, finally, what strategies to employ in order to profitably stimulate repeat purchase behaviour of the four main groups of Solosso's customers. The methods and strategies are expected to generate substantial incremental profits and may be implemented in other businesses as well.