Bibliography: leaves 216-250. / xii, 250 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / To determine the acute and subacute effects of therapeutic irradiation on oescophageal, gastric and intestinal function; the chronic effects of irradiation on gastric, intestinal and anorectal function, and, the effects of loperamide-N-oxide in patients with diarrhoea due to chronic radiation enteritis. / Thesis (M.D.)--University of Adelaide, Dept. of Medicine, 1996?

published_or_final_version / Physiology / Doctoral / Doctor of Philosophy

published_or_final_version / Paediatrics and Adolescent Medicine / Master / Master of Medical Sciences

Efeito do sistema é o nome dado ao decréscimo no desempenho do ventilador que surge quando a instalação deste no sistema não é feita de forma que seja permitido o desenvolvimento completo do escoamento nos trechos de duto em sua entrada ou saída. Esse efeito, muitas vezes não levado em conta durante o dimensionamento de ventiladores associados a sistemas de movimentação de ar, pode causar a insuficiência na vazão de ar ou na pressão requerida para um determinado processo ou objetivo. Este trabalho analisa, para um determinado caso de efeito do sistema, a influência dos parâmetros envolvidos no processo para se melhor compreender este fenômeno. É escolhida para o procedimento experimental, a faixa de velocidades de escoamento em que os dados de fatores do efeito do sistema variam em maior grau nas referências bibliográficas. A metodologia aplicada nos ensaios experimentais é baseada em bibliografias que estudaram diferentes formas de efeito do sistema. Os equipamentos utilizados no processo são escolhidos de forma a atender os fatores restritivos existentes no Laboratório de Instrumentação em Mecânica dos Fluidos da Escola Politécnica da Universidade de São Paulo. Os valores de fator do efeito do sistema obtidos experimentalmente são comparados com os da bibliografia, sendo encontradas diferenças que variam entre 0% e 58%. São buscadas formas de estimar o impacto de cada uma das variáveis envolvidas. O estudo apresentado aqui é de importância para a indústria, devido ao fato de que diferenças de até 200% surgem entre os cálculos de perda de carga que contabilizam o efeito do sistema e aqueles que não contabilizam. / System effect is the name given to the performance decrease of the fan that takes place when the installation of the fans in the system is in a form where the complete development of the flow is not possible to occur in the duct regions in the entrance and exit of the fan. This effect is frequently not considered during the dimensioning of ventilation systems and the selection of the fan for a given process or purpose, which may lead to deficiency in the flow and pressure values when compared to the requirements. The influence of each involved parameter was analyzed in this project for a specific case of system effect in order to better comprehend this phenomenon. The range of airflow speeds chosen for the experimental procedures defined was the one that differed the most in the bibliography. The methodology applied in the experiments was based on bibliography that studied different forms of system effect. The equipment used in the process was chosen to attend to the restrictive factors existent in the Laboratório de Instrumentação em Mecânica dos Fluidos from the Escola Politécnica da Universidade de São Paulo. The values of system effect obtained experimentally were compared to the bibliography, and differences between 0% and 58% were found. A way to estimate the impact of each involved variable was studied. The study present here is quite important to the industry, due to the fact that differences of up to 200% can be found between losses calculations that consider the system effect and those which do not.

Excitatory glutamatergic inputs from limbic regions such as the hippocampus and the basolateral amygdala (BLA), and dopaminergic inputs from the ventral tegmental area converge in the nucleus accumbens (NAc). It has been proposed that interactions between these glutamatergic and dopaminergic pathways play an important role in adaptive behaviors. The present thesis employed a multidisciplinary approach to study these interactions, with a specific emphasis on the importance of mesoaccumbens dopamine (DA) transmission, in order to obtain a better understanding of the neural mechanisms by which the NAc transforms signals from the temporal lobes into behavior. The experiments of Chapter 2 utilized extracellular single-unit recordings of individual NAc neurons in combination with electrochemical measures of DA efflux in the NAc. Recordings from NAc neurons which received input from the hippocampus but not the BLA revealed that increased efflux of mesoaccumbens DA, evoked by tetanic stimulation of the fimbria, potentiated hippocampal-evoked neural activity in these cells. These effects were mediated by both DA and NMDA receptors. Similar recordings from neurons which received converging input from both the hippocampus and the BLA revealed tetanic stimulation of the fimbria again potentiated hippocampal evoked spiking activity, while concurrently suppressing BLA-evoked spiking activity in the same neurons. The suppression of BLA-evoked spiking activity was activity-dependent, and was mediated by both D, and adenosine A, receptors. Chapter 3 showed that random foraging on a radial-arm maze, which is dependent on a neural circuit linking the hippocampus to the NAc, was correlated with an increase in mesoaccumbens DA extracellular levels, as measured with microdialysis. In Chapter 4, pharmacological blockade of DA or NMDA receptors in the NAc, or selective disruption of dopaminergic modulation of ventral subicular inputs to the NAc (using an asymmetrical infusion procedure) significantly disrupted random foraging. These effects were mediated by the Dl receptor. In Chapter 5, the present data are integrated with previous research to formulate a model of ventral striatal function. It is proposed that the NAc mediates behavior through distinct patterns of activity and inactivity driven by excitatory limbic input projecting to different groups of neural ensembles. Mesoaccumbens DA transmission plays an essential role in regulating the synchrony ensemble activity, augmenting activity in one ensemble while suppressing activity in another. It is argued that the modulatory effects of DA appears to be essential when an organism must switch from one form of adaptive behavior to another in response to a constantly changing environment.

背景黃芪是中醫藥中最常用的補益藥之一，現代研究發現其多糖類成分具有抗疲勞、抗氧他和免疫調節等作用，因此研究黃芪多糖的生理活性已成為研究黃芪藥理作用新的主流方向。由於多糖類物質分子量較大，單糖組成及組成方式多樣，所以對多糖的研究除生理活性外還需探討解析其他學特征。目的初步驗證黃芪多糖對免疫系統的生理活性及其自身他學組成，探討展望未來對黃芪多糖研究的新方向。方法本實驗採用水提醇沉法提取分離除黃芪粗多糖，經除蛋白及透析等操作純忙得到黃百多糖。採用高效凝膠色譜分離法及超高效液相色譜法分別求得黃芪多糖相對分子量大小及其單糖組成成分免疫活性探究使用RAW264.7 細胞系巨噬細胞，以脂多糖為陽性對照，採用MTT 法測試細胞毒性，計算加藥后一氧化氮及細胞因子IL-6 和TNF－α 生成量，評價黃芪多糖的免疫調節作用。結果黃芪多糖相對分子量為108.02kDa(±2.73kDa），由阿拉伯糖、葡萄糖、半乳糖、葡萄糖醛酸和半乳糖醛酸組成。MTT 實驗表明黃芪多糖對細胞無明顯毒性﹔ NO 及細胞因子IL-6 和TNF－α 生成量表明其具有免疫調節功能，且作用強度與黃芪多糖濃度在一定範圍內呈正相關。結論黃芪多糖具有免疫調節活性，但其組成成分較多，他學結構複雜，仍需要進行更多研究探討其作用機制及其他學結構與免疫調節機制的關係。【關鍵詞】黃芪多糖﹔化學組成﹔免疫活性

Efeito do sistema é o nome dado ao decréscimo no desempenho do ventilador que surge quando a instalação deste no sistema não é feita de forma que seja permitido o desenvolvimento completo do escoamento nos trechos de duto em sua entrada ou saída. Esse efeito, muitas vezes não levado em conta durante o dimensionamento de ventiladores associados a sistemas de movimentação de ar, pode causar a insuficiência na vazão de ar ou na pressão requerida para um determinado processo ou objetivo. Este trabalho analisa, para um determinado caso de efeito do sistema, a influência dos parâmetros envolvidos no processo para se melhor compreender este fenômeno. É escolhida para o procedimento experimental, a faixa de velocidades de escoamento em que os dados de fatores do efeito do sistema variam em maior grau nas referências bibliográficas. A metodologia aplicada nos ensaios experimentais é baseada em bibliografias que estudaram diferentes formas de efeito do sistema. Os equipamentos utilizados no processo são escolhidos de forma a atender os fatores restritivos existentes no Laboratório de Instrumentação em Mecânica dos Fluidos da Escola Politécnica da Universidade de São Paulo. Os valores de fator do efeito do sistema obtidos experimentalmente são comparados com os da bibliografia, sendo encontradas diferenças que variam entre 0% e 58%. São buscadas formas de estimar o impacto de cada uma das variáveis envolvidas. O estudo apresentado aqui é de importância para a indústria, devido ao fato de que diferenças de até 200% surgem entre os cálculos de perda de carga que contabilizam o efeito do sistema e aqueles que não contabilizam. / System effect is the name given to the performance decrease of the fan that takes place when the installation of the fans in the system is in a form where the complete development of the flow is not possible to occur in the duct regions in the entrance and exit of the fan. This effect is frequently not considered during the dimensioning of ventilation systems and the selection of the fan for a given process or purpose, which may lead to deficiency in the flow and pressure values when compared to the requirements. The influence of each involved parameter was analyzed in this project for a specific case of system effect in order to better comprehend this phenomenon. The range of airflow speeds chosen for the experimental procedures defined was the one that differed the most in the bibliography. The methodology applied in the experiments was based on bibliography that studied different forms of system effect. The equipment used in the process was chosen to attend to the restrictive factors existent in the Laboratório de Instrumentação em Mecânica dos Fluidos from the Escola Politécnica da Universidade de São Paulo. The values of system effect obtained experimentally were compared to the bibliography, and differences between 0% and 58% were found. A way to estimate the impact of each involved variable was studied. The study present here is quite important to the industry, due to the fact that differences of up to 200% can be found between losses calculations that consider the system effect and those which do not.

Excitatory glutamatergic inputs from limbic regions such as the hippocampus and the basolateral amygdala (BLA), and dopaminergic inputs from the ventral tegmental area converge in the nucleus accumbens (NAc). It has been proposed that interactions between these glutamatergic and dopaminergic pathways play an important role in adaptive behaviors. The present thesis employed a multidisciplinary approach to study these interactions, with a specific emphasis on the importance of mesoaccumbens dopamine (DA) transmission, in order to obtain a better understanding of the neural mechanisms by which the NAc transforms signals from the temporal lobes into behavior. The experiments of Chapter 2 utilized extracellular single-unit recordings of individual NAc neurons in combination with electrochemical measures of DA efflux in the NAc. Recordings from NAc neurons which received input from the hippocampus but not the BLA revealed that increased efflux of mesoaccumbens DA, evoked by tetanic stimulation of the fimbria, potentiated hippocampal-evoked neural activity in these cells. These effects were mediated by both DA and NMDA receptors. Similar recordings from neurons which received converging input from both the hippocampus and the BLA revealed tetanic stimulation of the fimbria again potentiated hippocampal evoked spiking activity, while concurrently suppressing BLA-evoked spiking activity in the same neurons. The suppression of BLA-evoked spiking activity was activity-dependent, and was mediated by both D, and adenosine A, receptors. Chapter 3 showed that random foraging on a radial-arm maze, which is dependent on a neural circuit linking the hippocampus to the NAc, was correlated with an increase in mesoaccumbens DA extracellular levels, as measured with microdialysis. In Chapter 4, pharmacological blockade of DA or NMDA receptors in the NAc, or selective disruption of dopaminergic modulation of ventral subicular inputs to the NAc (using an asymmetrical infusion procedure) significantly disrupted random foraging. These effects were mediated by the Dl receptor. In Chapter 5, the present data are integrated with previous research to formulate a model of ventral striatal function. It is proposed that the NAc mediates behavior through distinct patterns of activity and inactivity driven by excitatory limbic input projecting to different groups of neural ensembles. Mesoaccumbens DA transmission plays an essential role in regulating the synchrony ensemble activity, augmenting activity in one ensemble while suppressing activity in another. It is argued that the modulatory effects of DA appears to be essential when an organism must switch from one form of adaptive behavior to another in response to a constantly changing environment. / Arts, Faculty of / Psychology, Department of / Graduate

published_or_final_version / abstract / toc / Pharmacology / Master / Master of Philosophy

Since astronaut time and energy are at a premium, effective countermeasures must be designed to maximize benefits while minimizing time/energy cost. Therefore, our intent was to design and evaluate a low volume, high intensity resistance training program (RTP) on the preservation of knee extensor and plantar flexor size, strength and neuromuscular function in response to unloading. A total of 32 subjects participated. Sixteen men underwent 21 days of unilateral lower limb suspension (ULLS) and were assigned to control (no RTP) (ULLS-CON, n=8) or countermeasures (ULLS-CM, n=8). The remaining subjects were ambulatory for 21 days and were assigned to no RTP (n=8) or countermeasures (n=8). Countermeasure subjects performed RTP every third day during the suspension period (total=6). The RTP consisted of 2 maximal isometric contractions (MVC), 1 set of 10 concentric/eccentric isotonic repetitions, and 1 set to exhaustion, at 80% of 1-repetition maximum (1RM). There was no change in muscle function in ambulatory subjects. Whole muscle cross sectional area (CSA) measured by computed tomography (CT) decreased 7% (thigh) and 7.5% (calf) in ULLS-CON (p<0.05), and was unchanged in ULLS-CM. MVC decreased 16.5% in both quadricep and calf muscles in ULLS-CON (p<0.05) and increased 6% in the quadricep of ULLSCM (p<0.05). Maximal concentric (CNC) and eccentric (ECC) isokinetic strength decreased an average of 18% and 17% in the knee extensors and plantar flexors of ULLS-CON, respectively (p<0.05) and was unchanged in ULLS-CM. 1RM decreased 16% in both quadricep and calf of ULLS-CON (p<0.05) and was unchanged in ULLSCM. Knee extensor work capacity, evaluated during 30 maximal CNC contractions (3.14 rad•sec-'), decreased 18% in ULLS-CON (p<0.05). Neural activation of knee extensors and plantar flexors was measured by electromyography (EMG). Submaximal v.lat, v.med, gast and sol EMG increased in ULLS-CON (p<0.05) and was unaltered in ULLSCM. Maximal EMG decreased 20% and 26% in v.1at and v.med, respectively in ULLSCON (p<0.05). ULLS-CM showed a 15% and 28% increase in v.med and gast maximal EMG (p<0.05). These data suggest knee extensor and plantar flexor muscle size, strength and neuromuscular function were preserved during unloading using a low volume, high intensity RTP performed every third day. / School of Physical Education