Background: Fetal alcohol spectrum disorders (FASD), which are caused by prenatal alcohol exposure (PAE), affects people around the world. Certain communities in South Africa have among the highest reported incidences of fetal alcohol syndrome (FAS) in the world. Although PAE-related brain alterations have been widely documented, the mechanisms whereby alcohol affects the brain are not clearly understood. MRI relaxation parameters T1, T2, T2* and proton density (PD), are basic tissue properties that reflect the underlying biology. The present study aims to advance our understanding of how PAE alters the microstructural properties of tissue by examining PAE-related changes in these tissue parameters in adolescents with FASD. Methods: The final sample used in this study consisted of 53 children from a previously studied longitudinal cohort (Jacobson et al., 2008) and 12 additionally recruited subjects. Of the 65 participants, 18 were diagnosed with FAS or partial FAS (PFAS) and made up the FAS/PFAS group, 18 were diagnosed as heavily exposed non-syndromal (HE) and 29 were age matched controls. Subjects were scanned at the Cape Universities Body Imaging Centre (CUBIC) located at Groote Schuur Hospital on a 3T Siemens Skyra MRI. Structural images were obtained using the MEMPRAGE sequence. From these images T1, T2, T2* and PD parameter maps were constructed and segmented into 43 regions of interest (ROI) using Freesurfer, FSL and AFNI. Linear regression analyses were used to analyse group differences as well as correlations between parameter values and the amount of alcohol the mother consumed during pregnancy. Results: Significant T1 differences were found in the caudate, cerebellar cortex, hippocampus, accumbens, putamen, choroid plexus, ventral diencephalon (DC), right vessel and ventricles. Significant T2 differences were found in the caudate, brain stem, corpus callosum (CC), amygdala, cerebral cortex, choroid plexus, vessels and ventricles. Significant T2* differences were found in the cerebellar cortex, optic chiasm and ventricles. Significant PD differences were found in the hippocampus and left lateral ventricle. The exploratory nature of this study resulted in none of the results surviving FDR correction for multiple comparisons. Conclusions: Overall, our findings point to regional PAE-related increases in water content and cellular and molecular changes in underlying tissue of the anatomical structure. Exceptions were the right cerebral cortex, brain stem, hippocampus, amygdala and ventral diencephalon where our findings point to less free water and increased cell density, and cerebellar cortex where simultaneous reductions in T1 and T2* suggest the possibility of increased iron content. In highly myelinated white matter structures, such as the CC and optic chiasm, our results point to PAErelated demyelination, and possibly increased iron. These findings extend previous knowledge of effects of PAE and demonstrate that tissues are affected at a microstructural level.

The diploma thesis is focused on the determination of the content of phthalates (PAE) in printed and non-printed plastic packaging materials for meat products. There were analyzed 30 package samples. The sample area was 1 dm2. Concentrations of dibutyl phthalate (DBP) ranged from undetectable values (< 0.1) to 72.6 ug.dm-2 of the sample surface in printed packaging materials. In non-printed wraps it was from undetectable values (< 0.1) to 67.7 ug.dm-2 of the sample surface. Concentrations of di-2-ethylhexyl phthalate (DEHP) ranged from undetectable values (< 0.1) to 98.7 ug.dm-2 of the sample surface in printed packaging materials. In non-printed wraps it was from undetectable values (< 0.1) to 60.3 ug.dm-2 of the sample surface.

Modern RF and millimeter-wave communication links call for high-efficiency front end systems with high output power and high linearity to meet minimum transmission requirements. Advanced modulation techniques, such as orthogonal frequency-division multiplexing (OFDM) require a large power amplifier (PA) dynamic range due to the high peak-to-average power ratio (PAPR). This thesis provides the analysis, design, and experimental verification of a high-efficiency, high-linearity S-band Doherty power amplifier (DPA) based on the Class F PA. Traditional Class F PAs use harmonically tuned output matching networks to obtain up to 88.4% power-added efficiency (PAE) theoretically, however the amplifier experiences poor linearity performance due to switched mode operation, typically yielding less than 30dB C/I ratio [1]. The DPA overcomes this linearity limitation by using an auxiliary amplifier to boost output power when the amplifier is subject to a high input power due to its limited conduction cycle. The DPA also provides improved saturated output power back-off performance to maintain high PAE during operation. The DPA presented in this thesis optimizes PAE while maintaining linearity by employing harmonically tuned Class F amplifier topology on a primary and an auxiliary amplifier. A Class F PA is first designed and fabricated to optimize output network linearity – this is followed by a DPA design based on the fabricated Class F PA. A GaN HEMT Class F PA and DPA operating at 2.2GHz are implemented with the PAs measuring 40% and 45% PAE respectively while maintaining a 30dB carrier-to-intermodulation (C/I) ratio on a two-tone test. The PAE is characterized at maximum 21dBm input power per tone and 20MHz tone spacing. When subject to a single 24dBm continuous wave input tone, the Class F PA and DPA output 37dBm and 35.5dBm respectively. The PAs presented in the thesis provide over 30dB C/I ratio up to 21dBm input tones while maintaining over 40% PAE suitable for base station applications.

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Millimeter wave (mm-Wave) has become increasingly popular frequency band for next-generation high-speed wireless communications. In mm-Wave, the wireless channel path loss is severe, demanding a high output power in transmitters (Tx) to meet a required SNR in receivers (Rx). Due to the intractable speed-power tradeoff ingrained in silicon processes, however, achieving a high power at mm-Wave, particularly over W-band (> 90 GHz), is challenging in silicon power amplifiers. To relieve the output power burden, phased-arrays are widely adopted in mm-Wave wireless communication systems -- namely, by leveraging a parallel power combining in the space domain, inherent in the phased arrays, the required output power per array element can be reduced significantly with increasing array size. In large arrays ( > 100's -- 1000's number of arrays), the required output power per element could be small, typically around several 10's mW or less in silicon-based phased arrays. In such small-to-medium scale output power level, the static power dissipations by transistor knee voltage and passive components could be a significant portion of the output power, decreasing power efficiency of power amplifiers drastically. This poses a significant concern on the power efficiency of the large-scale silicon-based phased arrays in mm-Wave. Another critical problem in mm-Wave wireless systems design is the increase of passive reactive components loss caused by worsening skin depth effect and increasing dielectric loss through silicon substrate. This essentially degrades the reactive components quality factor (Q) and limits frequency selectivity of the silicon-based mm-Wave systems. This thesis tackles these two major technical challenges to provide high frequency selectivity with maintaining high power efficiency for future mm-Wave wireless systems over W-band and beyond. First, various high-efficiency techniques such as impedance tuning with a reactive component at a cascoding stage in conventional stacked power amplifiers or load-pull based inter-stage matching technique, rather than conventional conjugate matching, have been applied to W-band CMOS and SiGe BiCMOS amplifiers to improve power efficiency with 5-10 dBm output power level, suitable for a large phased array applications, as detailed in Chapter 2 and 3. Second, a 4-tap finite impulse response (FIR) filter based receiver architecture is presented in Chapter 4. The FIR filtered receiver leverages a sinc-pulse type frequency nulls built-in in the transmission-line based FIR filter's frequency response to increase frequency selectivity. The proposed FIR filtered receiver achieves > 40-dB image rejection by placing an image signal at the null frequency at D-band, one of the largest image rejection performance at the highest frequency band reported so far. / Ph. D. / Due to recent advances in Silicon based solid-state technologies, the interest towards the millimeter wave (mm-Wave) frequency band has been emerging for next-generation high-speed wireless communication applications. One of the most significant parameters in a communication system would be the output power of a transmitter. However, the output power is limited especially at mm-wave frequencies. A phased array is one of the viable solutions to overcome this burden by utilizing a parallel power combing in the space domain. The required output power per element can be relieved, typically around several tens of mill watts or less. There are two major factors limiting the output power, which are the high loss of passive and active devices. This dissertation presents solutions to overcome these challenges. In addition, a 4-tap finite impulse response (FIR) filter based receiver architecture is introduced, which rejects unwanted image signals in heterodyne systems by utilizing sinc-pulse type frequency nulls. The proposed FIR filter achieves more than 40 dB of image rejection at D-band (110-170 GHz), which is one of the highest filtering performance in the millimeter-wave frequency band.

Esta pesquisa apresenta o tema da formação de professores para atuar no ensino superior. Estudos apontam que o professor universitário no Brasil não tem recebido a devida formação para a docência pelas universidades ficando sua ação aquém da complexidade exigida para o ensino na Educação Superior. Na Universidade de São Paulo, a formação para a docência ocorre pela via do Programa de Aperfeiçoamento de Ensino (PAE-USP), no qual os pós-graduandos cumprem duas etapas: a preparação pedagógica e o estágio supervisionado em docência. O objetivo deste trabalho é investigar o Programa de Aperfeiçoamento do Ensino da Universidade de São Paulo como espaço institucional de formação de professores para o ensino superior, a partir da perspectiva dos seus egressos, que hoje atuam como docentes em instituições de ensino superior públicas brasileiras. O referencial teórico tem como base estudos sobre a universidade contemporânea, o cenário atual da formação de professores universitários, a docência universitária na perspectiva da complexidade, dos saberes da docência e do desenvolvimento profissional docente. A metodologia utilizada é de abordagem qualitativa, sendo utilizados como instrumentos de coleta de dados questionários e entrevistas semiestruturadas. Participaram da pesquisa 14 docentes de IES públicas brasileiras, que realizaram o Programa PAE na Faculdade de Ciências Farmacêuticas de Ribeirão Preto da USP entre 2005 e 2013. A análise dos dados foi realizada por meio da Análise de Conteúdo Análise Temática, utilizando-se de duas categorias criadas a priori: saberes da docência e desenvolvimento profissional. Os resultados apontam que o Programa PAE, na perspectiva dos seus participantes, possui mais significado na medida em que o estagiário tem maior contato com a prática docente. Os participantes reiteram a importância de espaços e programas para a formação docente para o Ensino Superior, inicial e continuada. / This research presents the theme of teacher training to work in higher education. Studies point out that the university professor in Brazil has not received the necessary training for teaching by the universities and their action falls short of the complexity required for teaching in Higher Education. At the University of São Paulo, training for teaching takes place through the Program for the Improvement of Teaching (PAE-USP), in which postgraduates fulfill two complementary stages: pedagogical preparation and supervised teaching. The objective of this work is to investigate the Program for the Improvement of Teaching at the University of São Paulo as an institutional space for teacher education for higher education, from the perspective of its alumni, who now act as teachers in Brazilian public higher education institutions. The theoretical framework is based on studies on the contemporary university, the current scenario of university teacher training, university teaching in the perspective of complexity, teaching knowledge and professional teacher development. The methodology used is a qualitative approach, being used as instruments of data collection questionnaires and semi-structured interviews. A total of 14 subjects, teachers of Brazilian public HEIs, who participated in the PAE Program at the Faculty of Pharmaceutical Sciences of Ribeirão Preto, USP, between 2005 and 2013, participated in the study. Data analysis was performed through Content Analysis - Thematic Analysis, Two categories created a priori. The results indicate that the PAE Program, from the perspective of its participants, has more meaning in that the trainee has more contact with the teaching practice. The participants reiterate the importance of spaces and programs for teacher education for Higher Education.

Esta pesquisa apresenta o tema da formação de professores para atuar no ensino superior. Estudos apontam que o professor universitário no Brasil não tem recebido a devida formação para a docência pelas universidades ficando sua ação aquém da complexidade exigida para o ensino na Educação Superior. Na Universidade de São Paulo, a formação para a docência ocorre pela via do Programa de Aperfeiçoamento de Ensino (PAE-USP), no qual os pós-graduandos cumprem duas etapas: a preparação pedagógica e o estágio supervisionado em docência. O objetivo deste trabalho é investigar o Programa de Aperfeiçoamento do Ensino da Universidade de São Paulo como espaço institucional de formação de professores para o ensino superior, a partir da perspectiva dos seus egressos, que hoje atuam como docentes em instituições de ensino superior públicas brasileiras. O referencial teórico tem como base estudos sobre a universidade contemporânea, o cenário atual da formação de professores universitários, a docência universitária na perspectiva da complexidade, dos saberes da docência e do desenvolvimento profissional docente. A metodologia utilizada é de abordagem qualitativa, sendo utilizados como instrumentos de coleta de dados questionários e entrevistas semiestruturadas. Participaram da pesquisa 14 docentes de IES públicas brasileiras, que realizaram o Programa PAE na Faculdade de Ciências Farmacêuticas de Ribeirão Preto da USP entre 2005 e 2013. A análise dos dados foi realizada por meio da Análise de Conteúdo Análise Temática, utilizando-se de duas categorias criadas a priori: saberes da docência e desenvolvimento profissional. Os resultados apontam que o Programa PAE, na perspectiva dos seus participantes, possui mais significado na medida em que o estagiário tem maior contato com a prática docente. Os participantes reiteram a importância de espaços e programas para a formação docente para o Ensino Superior, inicial e continuada. / This research presents the theme of teacher training to work in higher education. Studies point out that the university professor in Brazil has not received the necessary training for teaching by the universities and their action falls short of the complexity required for teaching in Higher Education. At the University of São Paulo, training for teaching takes place through the Program for the Improvement of Teaching (PAE-USP), in which postgraduates fulfill two complementary stages: pedagogical preparation and supervised teaching. The objective of this work is to investigate the Program for the Improvement of Teaching at the University of São Paulo as an institutional space for teacher education for higher education, from the perspective of its alumni, who now act as teachers in Brazilian public higher education institutions. The theoretical framework is based on studies on the contemporary university, the current scenario of university teacher training, university teaching in the perspective of complexity, teaching knowledge and professional teacher development. The methodology used is a qualitative approach, being used as instruments of data collection questionnaires and semi-structured interviews. A total of 14 subjects, teachers of Brazilian public HEIs, who participated in the PAE Program at the Faculty of Pharmaceutical Sciences of Ribeirão Preto, USP, between 2005 and 2013, participated in the study. Data analysis was performed through Content Analysis - Thematic Analysis, Two categories created a priori. The results indicate that the PAE Program, from the perspective of its participants, has more meaning in that the trainee has more contact with the teaching practice. The participants reiterate the importance of spaces and programs for teacher education for Higher Education.

Ce manuscrit de thèse décrit la synthèse et la caractérisation d'ionomères conducteurs protoniques pour une application en tant que membrane pour pile à combustible. La stratégie adoptée pour la synthèse de ces polymères repose sur la polycondensation directe de monomères fonctionnels. Pour ce faire, et dans le cadre d'un travail important de chimie organique, la synthèse de trois monomères sulfonés ainsi que de trois monomères phosphonés a été réalisée. Différents polymères perfluorés (polyperfluorocyclobutane (PFCB) et polyaryléthers (PAE) (Polyétheréther cétone (PEEK) et Polysulfone (PS), ont été obtenus par polycondensation directe de ces monomères fonctionnalisés. Il a été possible de synthétiser des copolymères séquencés (à blocs) et comportant un ou deux types de fonctions conductrices protoniques. Afin d'établir d'éventuelles relations structure-propriété pour ces polymères et l'influence du solvant dans la morphologie de la membrane, une étude de la morphologie a été réalisée à partir de plusieurs séries de polymères PAE et leurs analogues « statistiques ». Les valeurs de conductivité des polymères à blocs sont, en général, supérieures à celles de leurs analogues « statistiques ». Un PAE obtenu est particulièrement intéressant, il possède à la fois une conductivité (216 mS.cm 1) nettement supérieure au Nafion® et un gonflement plus faible. Le polymère perfluoré (PFCB) obtenu est également très prometteur : la conductivité enregistrée pour ce ionomères est de 138 mS/cm. Ce travail de thèse est, à notre connaissance, le premier exemple de synthèse d'un PFCB sulfoné par polymérisation directe d'un monomère fonctionnel mais il constitue également le premier exemple de synthèse de poly(aryléther)s à blocs sulfonés / phosphonés par copolymérisation directe de deux types de monomères fonctionnels / This thesis describes the synthesis and characterization of proton conducting polymers for application as membrane for fuel cells (PEMFC). The approach for the synthesis of polymers consists in creating polymers from direct polycondensation of functional monomers, in order to better control their final IEC. Three sulphonated monomers and three phosphonated monomers have been first synthetized. Different types of polyarylethers (one of them is both sulphonated and phosphonated) and one perfluorinated polymer (PFCB) have been synthetised by direct polycondensation of functional monomers. In order to explain the influence of the solvent in the final morphology of the membrane, and the relation between its structure and properties, one morphological study has been realized to the obtained polymers but also to their analogues “statistical” polymers. In general, the blocks polymers obtained the highest values of conductivity. One polyarylether seems particularly interesting, because its conductivity value is much higher than Nafion®’s, and has a smaller swelling value. The perfluorinated polymer has also an interesting conductivity value (138 mS/cm). This thesis work is, to the best of our knowledge, the first example of the synthesis of a sulphonated PFCB obtained by direct polycondensation but also the first example of synthesis of a both sulfonated/phosphonated polyarylethers by direct copolymerisation of to types of functional monomers