Made available in DSpace on 2016-04-28T20:38:14Z (GMT). No. of bitstreams: 1 Paula Land Curi.pdf: 642662 bytes, checksum: 14b5a878eb55c0eca2e589bd35ee879c (MD5) Previous issue date: 2012-05-04 / This thesis, developed from the perspective of Fundamental Psychopathology and psychoanalysis, aims to present some reflections on (in)fertility and spontaneous abortions, especially without determined causes, as a consequence of a clinical work with women who have experienced such phenomena. From the clinical situation, the development of this work led us built some directions to think of the metapsychology of portability/sustenance of a child. The text unfolds in six chapters. The first chapter is dedicated to consider the relations among clinical method, research on Fundamental Psychopathology and the paths that the author had gone through since her encounter with motherhood, and its clinic. The second chapter opens a dialogue between evolutionary biology and Fundamental Psychopathology, emphasizing human subject´s singularity and its mythical constructions. The third and fourth chapters seek to a bibliographic review of the phenomena treated, in other fields of knowledge, overcoming speeches that recur and do not effectively support explanations of these phenomena. The clinical case composes the fifth chapter of this work. Through it, we were led to raise some interrogations and reflect on the relation between (in)fertility manifested in body and life and the psychic plot of a psychopathological subject. In such a manner, we were encouraged to think and to highlight the tenuous relationships that are established in the field of procreation between nature and culture, especially on sixth chapter. For this, we turned to the myths and the evidences that are also present in an institution called maternity / Esta tese, desenvolvido na perspectiva da psicopatologia fundamental e da psicanálise, tem como objetivo apresentar algumas reflexões acerca das (in)fertilidades e dos abortamentos espontâneos, especialmente sem causas determinadas, a partir de desdobramentos de uma trabalho clínico com mulheres que vivenciaram tais fenômenos. O desenvolvimento da mesma levou-nos, a partir da situação clínica, a construir algumas direções para se pensar na metapsicologia da portação/sustentação de um filho. O texto desdobra-se em seis capítulos. O primeiro dedica-se a traçar considerações acerca do método clínico, da pesquisa em psicopatologia fundamental e os caminhos trilhados pela autora desde o seu encontro com a clínica da maternidade. O segundo abre uma interlocução entre a biologia evolutiva e a psicopatologia fundamental, enfatizando a singularidade do sujeito humano e as suas construções míticas. O terceiro e quarto capítulos buscam fazer uma revisão bibliográfica sobre os fenômenos tratados, recorrendo inclusive a diversos campos de saber. Ultrapassar discursos que se repetem e não sustentam de forma efetiva explicações acerca dos fenômenos estudados. O caso clínico compõe o quinto capítulo deste trabalho. Através dele, fomos conduzidos a levantar várias questões e refletir acerca da relação existente entre infertilidades que se manifestam no corpo e na vida e a trama psíquica do sujeito psicopatológico. Foi assim que fomos instigados a pensar e ressaltar as tênues relações que se estabelecem no campo da procriação entre natureza e cultura, especialmente no sexto capítulo. Para isso, recorremos aos mitos e as evidências que também se apresentam nas instituições hospitalares chamadas maternidades

Este trabalho apresenta uma reflexão acerca da natureza da entoação e de seu papel no funcionamento e no uso da linguagem, numa perspectiva interdisciplinar que traz para a discussão as contribuições de outras áreas do conhecimento que de uma maneira ou de outra se relacionam com a expressão na fala, seja por seus aspectos físicos, acústicos, seja por seus aspectos funcionais. Apresentamos evidências e argumentos que colocam a entoação como um fator primário na comunicação linguística que tem um papel fundamental na organização e transferência da informação de um sujeito a outro, tanto do ponto de vista da produção como da recepção. A tese aqui defendida é a de que a intenção comunicativa do falante o modo como este usa a linguagem enquanto ação junto a outros seres humanos é que determina a configuração melódica, precedendo a seleção e combinação dos constituintes do enunciado. Partimos da consideração da situação atual dos estudos prosódicos com respeito à entoação que encontramos descrita em Ladd (1996), Hirst e DiCristo (1998) e Fox (2000), entre outros, e apontamos alguns dos seus principais impasses e as questões epistemológicas relacionadas. Em seguida apresentamos as perspectivas de outras áreas de fora da linguística que direta ou indiretamente se reportam à entoação, seja como intenção, como é o caso da filosofia da linguagem, a sociologia, e a teoria literária, seja como melodia nas fronteiras do fazer teatral e da prática musical. Encontramos aí aproximações significativas entre as noções de estilo e gênero do discurso e a noção de intenção comunicativa que questionam a possibilidade de uma separação estanque entre o uso prático e o uso poético, musical, artístico da linguagem. Essa constatação nos levou a considerar uma grande categoria da atividade humana que denominamos práxis vocal que inclui, além da fala e do canto mais convencionais, formas intermediárias tais como narrativas orais, chamados, pregões, discursos políticos, declamações artísticas e religiosas como o recitativo e o salmodiar, entre outras. Estas formas empregam a modulação da frequência fundamental da voz de maneiras muito particulares e podem ser situadas na fronteira entre a linguagem e a música. Empreendemos, por isso, uma investigação acerca das relações, semelhanças e diferenças entre música e linguagem. Desta aproximação surgiu uma das ideias centrais desta tese, que é a relação entre estilo melódico e gênero de discurso nas manifestações orais. Percebemos que a realização de uma intenção comunicativa, seja numa fala espontânea, num discurso ou numa canção, começa com a escolha do gênero mais adequado à expressão do conteúdo desejado, e a partir dessa escolha é que fica determinado o estilo, que corresponde às regras de elaboração do discurso (linguístico, musical ou híbrido). A violação dessas regras que observamos quando há inconsistências melódicas na fala decorada, por exemplo, são decorrentes da necessidade de se criar uma melodia a partir de um texto já dado, fato que não acontece na fala espontânea. / This work presents a reflection about the nature of intonation, and about its role in how language works and it is used, within a interdisciplinary perspective that brings contributions from other areas that, in a way or another, relate to the issue of expression in speech, whether by its physical, acoustic features or by its functional aspects. We present evidences that show intonation as a primary factor in linguistic communication, having a fundamental role in organising and transferring information from one subject to another, from the point of view of production as well as perception. The main reasoning is that the communicative intention of the speaker - the way he uses languages as an action toward other human beings - determines the melodic configuration, that preceding selection and combination of the utterance contituents. Considering the recent development of investigation of prosody as it is described in Ladd (1996), Hirst e DiCristo (1998) and Fox (2000), among others, we show some of its hindrances and the epistemological issues related to them. Following that, we present perspectives brought from other areas outside linguistics that in a direct or indirect manner relate to the issues around intonation, whether as the speaker\'s intention, as we see in the field of philosophy of language, sociology and literary theory, or as a melodic elaboration in theater and musical practices. Within these new perspectives we found out striking similarities between the concepts of style and speech genre and the idea of communicative intention, that dispute a clear distinction of the practical use of language from its poetic, musical, artistic use. This remark have led us to consider a grand category of human activity that we named vocal praxis, including, besides ordinary speech and song, intermediate forms as those found in oral narratives, callings, auctioneering, political discourses and artistic declamation such as the recitative and chant. These forms employ the modulation of the fundamental frequency of the voice in very peculiar ways, and they may be situated close to the boundaries of speech and song. For that reason we endeavoured an inquiry on relationships, similarities and differences between music and language, This approximation produced one of the central ideas of this thesis, i.e. the connection of melodic style and speech genre along the continuum of vocal (oral) manifestations. We realized that the actualization of a communicative intention, whether in spontaneous speech, in a political discourse or in a song, begins with the choice of the adequate genre to the desired expression of the content; after this choice the style is determined, leading to the rules of elaboration of the particular discourse (linguistic, musical or hybrid). The violation of these rules, that we observe as melodic incoherences when someone speaks something by heart or reading aloud, are the consequence of an artificial situation that demands creating a new melody to a given text, which doesn\'t happen in spontaneous speech.

Neste trabalho resolvemos o problema da classicação dos possíveis esquemas de quebra de simetria que reproduzem as degenerescências do código genético na categoria dos grupos finitos simples, contribuindo assim para a busca de modelos algébricos para a evolução do código genético, iniciada por Hornos & Hornos. / In this work we solve the problem of classifying the possible symmetry breaking schemes based on simple finite groups that reproduce the degeneracies of the genetic code, thus contributing to the search for algebraic models that describe the evolution of the genetic code, initiated by Hornos & Hornos.

O aborto espontâneo recorrente (AER) é caracterizado pela ocorrência de três ou mais abortos consecutivos e acomete 2-4% das mulheres em idade fértil. A etiologia está associada a vários fatores de risco, tais como anomalias uterinas, aberrações cromossômicas, autoimunidade, trombofilias, elevação na concentração de homocisteína (tHcy), porém cerca de 40% dos casos permanece sem causa definida. O metabolismo de unidades de carbono desempenha papel fundamental na disponibilidade de folato na célula, sendo essencial para o desenvolvimento placentário e fetal. Deficiência de vitaminas que regulam este metabolismo, como o ácido fólico, e polimorfismos em genes que codificam enzimas relacionadas ao metabolismo de folato (MTHFR, RFC1, GCP2 e MTHFD1) podem levar à redução das concentrações desta vitamina e ao aumento das concentrações de tHcy. Objetivo foi avaliar a associação entre polimorfismos em genes relacionados ao metabolismo do folato (RFC1, GCP2, MTHFR e MTHFD1) e o risco de se ter AER, bem como avaliar a associação entre estes polimorfismos e as alterações nas concetranções de folato, cobalamina e homocisteína. Foram constituídos três grupos: AER primário: 117 mulheres com AER e nenhum feto viável; AER secundário: 139 mulheres com AER e pelo menos um feto viável; e Controle: 264 mulheres sem história de aborto espontâneo. Nenhuma das mulheres estava grávida no momento da coleta do sangue. Amostras de sangue foram obtidas para dosagens bioquímicas (folato, Cbl, tHcy, entre outras), imunológicas e extração de DNA genômico. As genotipagens foram feitas por PCR-RFLP ou PCR em tempo real. As concentrações séricas de folato e Cbl foram maiores no AER primário e secundário (p<0,05). A distribuição dos genótipos de todos os polimorfismos foi semelhante nos três grupos. O aumento nas concentrações de folato sérico (OR: 1,05, 95% IC: 1,03 - 1,07, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,016), tHcy (OR: 1,03, 95% IC: 0,97 - 1,11, p= 0,033) e T4 (OR: 1,02, 95% IC: 1,00 - 1,03, p= 0,006) e a presença de FAN reagente (1:160) (OR: 2,90, 95% IC: 1,25 - 6,75, p= 0,013) foram considerados fatores de risco para aborto primário. Para o aborto secundário, foram considerados fatores de risco o aumento nas concentrações de folato sérico (OR: 1,04, 95% IC: 1,02 - 1,05, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,019) e tHcy (OR: 1,05, 95% IC: 1,00 - 1,09, p= 0,039), maiores idades (OR: 1,02, 95% IC: 0,98 - 1,06, p= 0,031), hábito de fumar (OR: 2,54, 95% IC: 1,41 - 4,60, p= 0,002) e ter maior IMC (OR:1,42, 95% IC: 1,07 - 1,88, p= 0,015). Os polimorfismos estudados não foram associados ao maior risco de se ter AER, quando analisados isoladamente, e também não foram associados a alterações nas concentrações séricas de folato, Cbl e tHcy, com exceção do genótipo MTHFR 677TT, cujas portadoras apresentaram maior concentração de tHcy, quando comparadas com as portadoras de genótipos 677CC e 677CT nos três grupos. As variáveis concentrações de folato, Cbl, tHcy e T4 e presença de FAN reagente foram associadas ao maior risco de se ter aborto primário. As variáveis idade, IMC, tabagismo, concentrações de folato, Cbl e tHcy foram associadas ao maior risco de aborto secundário. / The recurrent spontaneous abortion (RSA) is characterized by the occurrence of three or more consecutive miscarriages and affects 2-4% of women of childbearing age. The etiology is associated with several risk factors such as uterine abnormalities, chromosomal aberrations, autoimmunity, thrombophilia, increased concentration of homocysteine (tHcy). About 40% of cases remains unknown cause. The units of carbon metabolism plays an essential role in the availability of the cell folate, is essential for the placental and fetal development. A deficiency of the vitamins that regulate this metabolism, like folic acid, and polymorphisms in genes encoding enzymes related to folate metabolism (MTHFR, RFC1, and GCP2 MTHFD1) may lead to decreased concentrations of this vitamin and increased concentrations of tHcy. Objective was to evaluate the association between polymorphisms in genes related to folate metabolism (RFC1, GCP2, MTHFD1 and MTHFR) and the risk of having AER, and to evaluate the association between these polymorphisms and changes in concetranções folate, cobalamin, and homocysteine. Three groups were divided: AER primary: 117 women with RSA and no viable fetus, AER secondary: 139 women with RSA and at least one viable fetus and Control: 264 women with no history of miscarriage. None of the women was pregnant at time of blood collection. Blood samples were taken for biochemical (folate, Cbl, tHcy, etc.), immunological and genomic DNA extraction. The genotyping were carried out by PCR-RFLP or real time PCR. Serum concentrations of folate and Cbl were higher in groups 1 and 2 (p <0.05). The distribution of genotypes of MTHFR c.677C> T, MTHFR c.1298A> C, MTHFD1 c.1958G> A, RFC1 c.80G>GCP2 A and c.1561C> T was similar among the three groups. The increased concentrations of serum folate (OR: 1.05, 95% CI: 1.03 - 1.07, p <0.001), Cbl (OR: 1.00, 95% CI: 1.00 to 1.00, p = 0.016), tHcy (OR: 1.03, 95% CI: 0.97 to 1.11, p = 0.033) and T4 (OR: 1.02, 95% CI: 1.00 to 1.03, p = 0.006) and the presence of ANA (1:160) (OR: 2.90, 95% CI: 1.25 - 6.75, p = 0.013) were considered risk factors primary for abortion. For secondary abortion, were considered risk factors increased the concentrations of serum folate (OR: 1.04, 95% CI: 1.02 - 1.05, p <0.001), cobalamin (OR: 1.00, 95 % CI: 1.00 to 1.00, p = 0.019) and tHcy (OR: 1.05, 95% CI: 1.00 to 1.09, p = 0.039), higher age (OR: 1.02, 95% CI: 0.98 to 1.06, p = 0.031), cigarette smoking (OR: 2.54, 95% CI: 1.41 to 4.60, p = 0.002) and had a higher BMI (OR : 1,42,95% CI: 1.07 to 1.88, p = 0.015). The studied polymorphisms were not associated with increased risk of having RSA when analyzed separately, and were not associated with changes in serum folate, Cbl and tHcy, with the exception of the MTHFR 677TT genotype, whose patients had a higher concentration of total tHcy compared with those with 677CC and 677CT genotypes in the three groups. The variable concentrations of folate, Cbl, tHcy, and T4, presence of ANA and have been associated with increased risk for miscarriage primary. The variables age, BMI, smoking, concentrations of folate, Cbl and tHcy were associated with increased risk of secondary miscarriage.

Yao Jun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Leung, Siu Lun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 153-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

With increasing amounts of data being collected in various fields of neuroscience, there is a growing need for robust techniques for the analysis of this information. This thesis focuses on the evaluation and development of quantitative frameworks for the analysis and classification of neuronal data from a variety of contexts. Firstly, I investigate methods for analysing spontaneous neuronal network activity recorded on microelectrode arrays (MEAs). I perform an unbiased evaluation of the existing techniques for detecting ‘bursts’ of neuronal activity in these types of recordings, and provide recommendations for the robust analysis of bursting activity in a range of contexts using both existing and adapted burst detection methods. These techniques are then used to analyse bursting activity in novel recordings of human induced pluripotent stem cell-derived neuronal networks. Results from this review of burst analysis methods are then used to inform the development of a framework for characterising the activity of neuronal networks recorded on MEAs, using properties of bursting as well as other common features of spontaneous activity. Using this framework, I examine the ontogeny of spontaneous network activity in in vitro neuronal networks from various brain regions, recorded on both single and multi-well MEAs. I also develop a framework for classifying these recordings according to their network type, based on quantitative features of their activity patterns. Next, I take a multi-view approach to classifying neuronal cell types using both the morphological and electrophysiological features of cells. I show that a number of multi-view clustering algorithms can more reliably differentiate between neuronal cell types in two existing data sets, compared to single-view clustering techniques applied to either the morphological or electrophysiological ‘view’ of the data, or a concatenation of the two views. To close, I examine the properties of the cell types identified by these methods.

café é a segunda bebida mais consumida no mundo, ficando atrás apenas da água; o Brasil figura como o maior produtor e exportador desta commodity no cenário global. Apesar de possuir uma cadeia altamente consolidada em nível global, mudanças e refinamentos tecnológicos estão em constante evolução, visando melhoria ou elevação da qualidade final da bebida, para atender a mercados cada vez mais exigentes. As interações entre os fatores edafoclimáticos, as formas de processamento, secagem, armazenagem e torrefação, implicam nos resultados sensoriais, que são desempenhados pelos Q-Graders de café, consequentemente, afetam o preço final do produto. Pesquisas recentes vêm demonstrando, que mesmo por trás de toda complexidade, que envolve a descrição da qualidade do café, é possível modificar o perfil sensorial da bebida, com controles mais precisos no processamento da matéria após a colheita. Tais indicativos estão inerentes aos processos de fermentações que ocorrem nos frutos, sendo que as fermentações podem conferir notas especiais de aroma, fragrância e acidez, bem como prejudicar a qualidade, quando não bem controlada. Com objetivo de elevação, melhoria e maior controle de processo na fase via-úmida, esta tese aplicou quatro formas de processamento por via-úmida, em seis estratos de altitude distintos, visando potencializar a qualidade final da bebida e estimar melhores métodos para cada faixa de altitude, com base nos fatores edafoclimáticos e nos fatores de ordem de processamento (fermentações espontâneas e induzidas). A qualidade final dos cafés foi mensurada por meio de resultados sensoriais, físico-químicos e cromatográficos, para que fosse possível determinar os melhores métodos de processamento por via-úmida para zonas de produção montanhosas Além da relação do processamento, estudaram-se formas de se introduzir maior acurácia ao processo de análise sensorial, objetivando redução da subjetividade. Os resultados foram empreendidos mediante análise de variância conjunta de experimentos, para os resultados sensoriais e físico-químicos (compostos fenólicos, acidez titulável total e pH), sendo as médias comparadas pelo teste de Tukey, considerando o nível de significância de 5%, e os modelos de regressão foram testados pelo teste F e os parâmetros pelo teste t. Além das análises de variância, adotou-se o método de agrupamento hierárquico com ligação completa, para as análises multivariadas. Os resultados indicam que o uso de cultura de arranque na fase de fermentação por via-úmida constitui em uma alternativa relevante para zonas menos elevadas, onde naturalmente os cafés tendem a notas sensoriais mais baixas, quando aplicados métodos tradicionais, e que as fermentações espontâneas possuem maior potencial de entrega de resultados sensoriais em faixas acima dos 900 metros de altitude. Os resultados demonstram que o processamento adotado após a colheita pode ser determinante para a formação do perfil sensorial, físico-químico e cromatográfico que o café terá, indicando que o controle de processo constitui em uma fase indispensável no pós-colheita. Tais evidências indicam que a qualidade pode ser modificada, para atender determinados nichos de mercado, visando à produção de um produto mais consistente e que dependa menos dos fatores climáticos ou do acaso. / Coffee is the second most consumed drink in the world, behind only water, Brazil figures as the largest producer and exporter of this commodity in the global scenario. Despite having a highly consolidated chain globally, technological and refinements changes are constantly evolving, aimed at improving or raising the final quality of the drink, to meet increasingly demanding markets. The interactions between the edaphoclimatic factors, the forms of processing, drying, storage and roasting, imply in the sensorial results, which are performed by the coffee tasters, consequently affect the final price of the product. Recent researches have shown that even behind all complexity, which involves the description of the quality of the coffee, it is possible to modify the sensorial profile of the beverage, with more precise controls in the processing of the matter, after the harvest. Such indications are inherent to the fermentation processes that occur in the fruits, and the fermentations can confer special notes of aroma, fragrance and acidity, as well as impair quality, when not well controlled. With objective of elevation, improvement and greater process control in the wet phase. This thesis applied four forms of wet processing in six distinct altitude strata, aiming at enhancing the final quality of the beverage and estimating better methods for each altitude range, based on edaphoclimatic factors, and processing order factors (spontaneous and induced fermentations). The final quality of the coffees was measured by sensorial, physico-chemical and chromatographic results, to determine the best wet processing methods for mountainous production areas In addition to the processing relationship, we studied ways to introduce greater accuracy to the process of sensory analysis, aiming to reduce subjectivity. The results were carried out through the analysis of joint variance of experiments for the sensory and physicochemical results (phenolic compounds, total titratable acidity and pH). The averages were compared by Tukey's test, considering a significance level of 5% and the regression models were tested by the F test and the parameters by the t test. In addition to the variance analysis, the hierarchical grouping method with complete linkage was used for the multivariate analysis. The results indicate that the use of starter culture in the wet fermentation phase constitutes a relevant alternative for less elevated areas, where naturally the coffees tend to lower sensorial scores when traditional methods are applied and that spontaneous fermentations have greater potential for delivery of sensory results in bands above 900 meters altitude. The results show that the post-harvest processing can be determinant for the formation of the sensorial, physico-chemical and chromatographic profile that the coffee will have, indicating that the process control is an indispensable post-harvest phase. Such evidence indicates that quality can be modified to meet certain market niches, aiming at producing a product that is more consistent and less dependent on climatic or chance factors.

The aim of this research was to identify the molecular mechanisms that promote spontaneous activation in rat eggs after their recovery from the oviduct. Typically, mammalian eggs await fertilisation arrested at the second metaphase II of meiosis. However, ovulated rat eggs spontaneously enter anaphase II when exposed to in vitro culture. After extrusion of the second polar body, these spontaneously activated eggs do not proceed to interphase but become arrested at metaphase III stage with chromatids scattered in the egg cytoplasm. This instability may be one factor that has made it more difficult to establish reliable protocols for somatic cell nuclear transfer in rats. The triggers of spontaneous activation and signalling pathways leading to the metaphase III progression are largely unknown. Analyses of signalling pathways that are involved in the regulation of final stages of meiosis during fertilisation revealed several anomalies that were associated with spontaneous activation and the transition from metaphase II to metaphase III. Metaphase II arrested eggs usually exhibit an increased level of maturation promoting factor (MPF) activity. Spontaneous activation in rat eggs was associated with a drop in MPF activity at the time of the second polar body extrusion. MPF is composed of a catalytic subunit, CDK1, and a regulatory subunit, cyclin B1. Interestingly, the level of cyclin B1 was stable throughout spontaneous activation. Post-translational modifications of CDK1 can influence MPF activity: whereas no inhibitory phosphorylation on Tyr15 of CDK1 was found; a decrease in activating Thr161 phosphorylation of CDK1 was associated with the time of the second polar body extrusion, and hence could contribute to the transient MPF inactivation. MAPK (p42/p44) activity has been shown to decrease during egg activation in fertilisation. By contrast, during spontaneous activation, MAPK (p42/p44) remained active and thus resembled the profile usually found between two meiotic divisions (metaphase I to metaphase II). Securin, a protein which prevents premature chromatid separation, was degraded in eggs going through spontaneous activation. Cytostatic factor (CSF) is a biochemical activity, which enables stable metaphase II arrest in ovulated eggs of vertebrates. Recently, the endogenous meiotic inhibitor 2, EMI2, was confirmed as the major component of CSF. For egg activation to occur, the CSF must be destroyed. At the beginning of egg activation, Ca2+/calmodulin kinase (CaMKII) promotes posttranslational modifications of EMI2, leading to its degradation. In the rat, inhibition of CaMKII activity stably prevented the onset of spontaneous activation in a subset of metaphase II eggs. However, no degradation of EMI2 protein was found at the start of abortive metaphase II exit. This finding revealed that one of the central elements of the CSF pathway, EMI2, could be preserved in the rat eggs going through spontaneous activation. In order to study the mechanisms regulating EMI2 stability in rat oocyte maturation and spontaneous activation, functional analysis of ectopically expressed synthetic mRNA was performed. The mechanism enabling EMI2 degradation became active 12 hours after the start of oocyte maturation. The C-terminal fragment of EMI2, known to be non-degradable in Xenopus oocyte maturation, was significantly more stable than the full-length counterpart in matured rat eggs but not during oocyte maturation. Interestingly, C-terminal EMI2 became degraded in parthenogenetic rat embryos. This indicated that additional not previously reported mechanisms responsible for EMI2 degradation might exist in the rat. The microinjection of metaphase II rat eggs with the C-terminal fragment of EMI2 or IVT full-length EMI2 protein had little effect on the progression of spontaneous activation. Taken together, these observations suggest that abortive spontaneous activation in rat eggs was a result of incomplete engagement of signalling pathways normally triggered in fertilisation or parthenogenetic activation. Activation of CaMKII initiated pathways that allowed anaphase entry and chromatid segregation. At the same time, not all pathways normally triggered during fertilisation or parthenogenetic activation were fully engaged, possibly due to the presence of non-degraded component of CSF. Abortive incomplete activation results in the re-establishment of high level of MPF activity in metaphase III eggs. Early prevention of CaMKII activation, perhaps by blocking [Ca2+ i] signalling, may provide a means of holding ovulated eggs at metaphase II prior to enucleation and somatic cell nuclear transfer.

by Ma Wing-Kin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 121-124). / Chapter 1 --- Introduction to Otoacoustic Emissions --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Clinical Significance of the OAEs --- p.2 / Chapter 1.3 --- Classes of OAEs --- p.3 / Chapter 1.4 --- The Distortion Product OAEs --- p.4 / Chapter 1.4.1 --- Measurement of DPOAEs --- p.5 / Chapter 1.4.2 --- Some Properties of DPOAEs --- p.8 / Chapter 1.4.3 --- Noise Reduction of DPOAEs --- p.8 / Chapter 1.5 --- Goal of this work and Organization of the Thesis --- p.9 / Chapter 2 --- Review to some Topics in Narrowband Signal Estimation --- p.11 / Chapter 2.1 --- Fourier Transforms --- p.12 / Chapter 2.2 --- Periodogram ´ؤ Classical Spectrum Estimation Method --- p.15 / Chapter 2.2.1 --- Signal-to-Noise Ratios and Equivalent Noise Bandwidth --- p.17 / Chapter 2.2.2 --- Scalloping --- p.18 / Chapter 2.3 --- Maximum Likelihood Estimation --- p.19 / Chapter 2.3.1 --- Finding of the ML Estimator --- p.19 / Chapter 2.3.2 --- Properties of the ML Estimator --- p.21 / Chapter 3 --- Review to Adaptive Notch/Bandpass Filter --- p.23 / Chapter 3.1 --- Introduction --- p.23 / Chapter 3.2 --- Filter Structure --- p.24 / Chapter 3.3 --- Adaptation Algorithms --- p.25 / Chapter 3.3.1 --- Least Squares Method --- p.25 / Chapter 3.3.2 --- Least-Mean-Squares Algorithm --- p.27 / Chapter 3.3.3 --- Recursive-Least-Squares Algorithm --- p.28 / Chapter 3.4 --- LMS ANBF Versus RLS ANBF --- p.31 / Chapter 3.5 --- the IIR filter Versus ANBF --- p.31 / Chapter 4 --- Fast RLS Adaptive Notch/Bandpass Filter --- p.33 / Chapter 4.1 --- Motivation --- p.33 / Chapter 4.2 --- Theoretical Analysis of Sample Autocorrelation Matrix --- p.34 / Chapter 4.2.1 --- Solution of Φ (n) --- p.34 / Chapter 4.2.2 --- Approximation of Φ (n) --- p.35 / Chapter 4.3 --- Fast RLS ANBF Algorithm --- p.37 / Chapter 4.4 --- Performance Study --- p.39 / Chapter 4.4.1 --- Relationship to LMS ANBF and Bandwidth Evaluation . --- p.39 / Chapter 4.4.2 --- Estimation Error of Tap Weights --- p.40 / Chapter 4.4.3 --- Residual Noise Power of Bandpass Output --- p.42 / Chapter 4.5 --- Simulation Examples --- p.43 / Chapter 4.5.1 --- Estimation of Single Sinusoid in Gaussian White Noise . --- p.43 / Chapter 4.5.2 --- Comparing the Performance of IIR Filter and ANBFs . . --- p.44 / Chapter 4.5.3 --- Harmonic Signal Enhancement --- p.45 / Chapter 4.5.4 --- Cancelling 50/60Hz Interference in ECG signal --- p.46 / Chapter 4.6 --- Simulation Results of Performance Study --- p.52 / Chapter 4.6.1 --- Bandwidth --- p.52 / Chapter 4.6.2 --- Estimation Errors --- p.53 / Chapter 4.7 --- Concluding Summary --- p.55 / Chapter 4.8 --- Appendix A: Derivation of Ts --- p.56 / Chapter 4.9 --- Appendix B: Derivation of XT(n)Λ(n)ΛT(n)X(n) --- p.56 / Chapter 5 --- Investigation of the Performance of two Conventional DPOAE Estimation Methods --- p.58 / Chapter 5.1 --- Motivation --- p.58 / Chapter 5.2 --- The DPOAE Signal Model --- p.59 / Chapter 5.3 --- Preliminaries to the Conventional Methods --- p.60 / Chapter 5.3.1 --- Conventional Method 1: Constrained Stimulus Generation --- p.60 / Chapter 5.3.2 --- Conventional Method 2: Windowing --- p.61 / Chapter 5.4 --- Performance Comparison --- p.63 / Chapter 5.4.1 --- Sidelobe Level Reduction --- p.63 / Chapter 5.4.2 --- Estimation Accuracy --- p.65 / Chapter 5.4.3 --- Noise Floor Level --- p.67 / Chapter 5.4.4 --- Additional Loss by Scalloping --- p.68 / Chapter 5.5 --- Simulation Study --- p.69 / Chapter 5.5.1 --- Sidelobe Suppressions of the Windows --- p.69 / Chapter 5.5.2 --- Mean Level Estimation --- p.70 / Chapter 5.5.3 --- Mean Squared Error Analysis --- p.71 / Chapter 5.6 --- Concluding Summary --- p.75 / Chapter 5.7 --- Discussion --- p.75 / Chapter 5.8 --- Appendix A: Cramer-Rao Bound of the DPOAE Level Estimation --- p.76 / Chapter 6 --- Theoretical Considerations of Maximum Likelihood Estimation for the DPOAEs --- p.77 / Chapter 6.1 --- Motivation --- p.77 / Chapter 6.2 --- Finding of the MLEs --- p.78 / Chapter 6.2.1 --- First Form: Joint Estimation of DPOAE and Artifact Pa- rameter --- p.79 / Chapter 6.2.2 --- Second Form: Artifact Cancellation --- p.80 / Chapter 6.3 --- Relationship of CM1 to MLE --- p.81 / Chapter 6.4 --- Approximating the MLE --- p.82 / Chapter 6.5 --- Concluding Summary --- p.84 / Chapter 6.6 --- Appendix A: Equivalent Forms for the Minimum Least Squares Error --- p.85 / Chapter 7 --- Optimum Estimator Structure and Artifact Cancellation Ap- proaches for the DPOAEs --- p.87 / Chapter 7.1 --- Motivation --- p.87 / Chapter 7.2 --- The Optimum Estimator Structure --- p.88 / Chapter 7.3 --- References and Frequency Offset Effect --- p.89 / Chapter 7.4 --- Artifact Canceling Algorithms --- p.92 / Chapter 7.4.1 --- Least-Squares Canceler --- p.93 / Chapter 7.4.2 --- Windowed-Fourier-Transform Canceler --- p.93 / Chapter 7.4.3 --- FRLS Adaptive Canceler --- p.95 / Chapter 7.5 --- Time-domain Noise Rejection --- p.97 / Chapter 7.6 --- Regional Periodogram --- p.98 / Chapter 7.7 --- Experimental Results --- p.99 / Chapter 7.7.1 --- Artifact Cancellation via External Reference --- p.99 / Chapter 7.7.2 --- Artifact Cancellation via Internal Reference --- p.99 / Chapter 7.7.3 --- Artifact Cancellation in presence of Transient Noise --- p.101 / Chapter 7.7.4 --- Illustrative Example: DPgrams --- p.102 / Chapter 7.8 --- Conclusion and Discussion --- p.111 / Chapter 7.9 --- Appendix A: Derivation of the Parabolic Interpolation Method . --- p.113 / Chapter 7.10 --- Appendix B: Derivation of Weighted-Least-Squares Canceler . . --- p.114 / Chapter 8 --- Conclusions and Future Research Directions --- p.118 / Chapter 8.1 --- Conclusions --- p.118 / Chapter 8.2 --- Future Research Directions --- p.119 / Bibliography --- p.121