Atmospheric nitrous acid (HONO) is a significant and sometimes dominant OH source at polar region. An improved method of detecting HONO is developed using photo-fragmentation and laser-induced fluorescence (LIF). The detection limit of this method is 2-3 pptv for ten-minute integration time with 35% uncertainty. The abundance of laser-induced fluorescence (LIF) HONO measurements during ANTCI (Antarctic troposphere chemistry investigation) 2003 exceeds the pure gas phase model predictions by a factor of 1.92±0.67, which implies snow emission of HONO. A 1D air-snowpack model of HONO was developed and constrained by observed chemistry and meteology data. The 1D model includes pure gas phase chemical mechanisms, molecular diffusion and mechanical dispersion, windpumping in snow, gas phase to quasi-liquid layer phase HONO transfer and quasi-liquid layer nitrate photolysis. Based on the air-snowpack model, snow emission of HONO is highly likely and will be transported to place of the measurements. The pH, thickness of quasi liquid layer and contineous nitrite measurement are key factors to calibrate and validate the air snowpack model.

A series of detailed laboratory investigations were conducted to examine low solubility gas transfer across wind-forced wavy air-water interfaces. The study focuses on the increase in gas flux associated with the microphysical interfacial wind momentum exchange and the complex wave coupled hydrodynamics. Key elements of the laboratory investigations included the measurement of hydrodynamic behaviour within the aqueous viscous sub-layer using a particle image velocimetry (PIV) system and the development of a Laser Induced Fluorescent (LIF) system capable of measuring reliable dissolved oxygen concentration profiles to within 28??m of the air-water interface. Major achievements and findings included: 1. The first phase resolved gas flux measurements along wind forced microscale waves, indicating the highest mean gas fluxes are located in the wave troughs. This finding demonstrated the relative importance of wave orbital straining in gas flux enhancement; a wave coupled hydrodynamic process whose significance has previously been neglected. 2. The relative contributions to gas flux from wind shear, wave orbital straining, increased surface area of the waves, parasitic capillary ripples and microscale breaking are quantified with respect to friction velocity, wave steepness and an efficiency of microscale wave breaking. The parasitic capillary ripples are shown to have a negligible role in gas enhancement. A hybrid model is developed to estimate the gas flux based on both wind and wave characteristics. 3. Gas enhancement due to microscale wave breaking and the significance of the highly localised subduction at the toe of the spilling region on the leeward face of the wave crests was investigated using data from the LIF experiments. The highly localised subduction was shown to substantially reduce the thickness of the diffusion sub-layer, resulting in an increase in gas flux when waves transitioned from the incipient breaking to the microscale breaking wave form. 4. Consideration of previously unidentified optical distortions in LIF imagery due to non-linear effects is presented that is critical for robust LIF data processing and experimental design. A formal mathematical description of optical distortions has been developed and presented.

Doctor of Philosophy(PhD) / This body of research uses numerical and experimental investigative techniques to further the understanding of autoignition. Hydrogen/nitrogen and methane/air fuel configurations of turbulent lifted flames in a vitiated coflow burner are used as model flames for this investigation. Characterisation was undertaken to understand the impact of controlling parameters and the overall behaviour of the flames, and to provide a body of data for modelling comparisons. Modelling of the flames was conducted using the PDF-RANS technique with detailed chemistry incorporated using In-situ Adaptive Tabulation (ISAT) within the commercial CFD package, FLUENT 6.2. From these investigations, two numerical indicators for autoignition were developed: convection-reaction balance in the species transport budget at the mean flame base; and the build-up of ignition precursors prior to key ignition species. These indicators were tested in well defined autoignition and premixed flame cases, and subsequently used with the calculated turbulent lifted flames to identify if these are stabilised through autoignition. Based on learnings from the modelling, a quantitative, high-resolution simultaneous imaging experiment was designed to investigate the correlations of an ignition precursor (formaldehyde: CH2O) with a key flame radical (OH) and temperature. Rayleigh scattering was used to measure temperature, while Laser Induced Fluorescence (LIF) was used to measure OH and CH2O concentrations. The high resolution in the Rayleigh imaging permitted the extraction of temperature gradient data, and the product of the OH and CH2O images was shown to be a valid and useful proxy for peak heat release rate in autoigniting and transient flames. The experimental data confirmed the presence of formaldehyde as a precursor for autoignition in methane flames and led to the identification of other indicators. Sequenced images of CH2O, OH and temperature show clearly that formaldehyde exists before OH and peaks when autoignition occurs, as confirmed by images of heat release. The CH2O peaks decrease later while those of OH remain almost unchanged in the reaction zone.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.

Base teórica: O processo de implantação do embrião no ser humano é extremamente complexo e, ao mesmo tempo, essencial para que a mulher possa engravidar. Neste processo, em que o endométrio precisa sofrer uma série de mudanças para tornar-se receptivo, a adequada expressão de MFG-E8 (milk fat globule epidermal growth factor 8), seu receptor a integrina αvβ3 e LIF (leukemia inhibitory factor) parecem ter um papel importante. Além do mais, mulheres com infertilidade e endometriose podem apresentar a falha de implantação como uma grande barreira para obter seu sucesso terapêutico. Objetivos: Avaliar o papel de MFG-E8 e do seu receptor integrina αvβ3 em um modelo de implantação in vitro com uma linhagem celular trofoblástica e outra de epitélio endometrial. Comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio de pacientes férteis e inférteis com endometriose durante a janela de implantação. Métodos: No primeiro ensaio, utilizando-se uma linhagem celular bem diferenciada de adenocarcinoma de endométrio (células Ishikawa) e uma linhagem de coriocarcinoma de trofoblasto, o modelo in vitro de implantação humana foi estabelecido. Para investigação do impacto do bloqueio de MFG-E8 e integrina αvβ3, ambas linhagens celulares foram pré-tratadas com anticorpos contra estas proteínas em diferente concentrações antes do ensaio de adesão. No ensaio subsequente, para comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio humano, foram realizadas biópsias no período da janela de implantação (LH+7 a LH+10) com cateter de Pipelle. As amostras foram submetidas a imunohistoquímica, e analisadas através do HSCORE. Resultados: Na avaliação in vitro observamos que as células Ishikawa pré-tratadas com anticorpo anti-MFG-E8 causaram diminuição da adesão das esferas Jar dose-dependente. Por outro lado, o pré-tratamento das esferas Jar não resultou em diminuição significativa da adesão. Pré-tratamento com anticorpos anti-integrina αvβ3, tanto de células Ishikawa como de esferas Jar, causaram inibição significativa, dose-dependente, da adesão das esferas. A análise imunohistoquímica das biópsias realizadas durante a janela de implantação mostrou uma expressão aumentada de MFG-E8 em pacientes com endometriose e infertilidade. Além do mais, houve expressão diminuída de LIF no grupo em estudo. Contudo, não houve diferença estatisticamente significativa na expressão de integrina αvβ3 entre os grupos em estudo. Conclusão: Este estudo demonstrou que, quando se bloqueia MFG-E8 ou seu receptor integrina αvβ3 em células Ishikawa em um modelo in vitro, ocorre uma diminuição de adesão das células Jar. Além do mais, bloqueando-se a integrina αvβ3 nas esferas Jar, também ocorre uma diminuição da adesão destas nas células Ishikawa. No entanto, quando estudamos o endométrio in vivo de pacientes com endometriose e infertilidade, encontramos a expressão aumentada de MFG-E8 e diminuída de LIF durante a janela de implantação no endométrio. / Background: The human implantation process is very complex and, at the same time, it is essential for women to achieve pregnancy. In this process, where the human endometrium must go through a lot of changes in order to become receptive, an adequate expression of MFG-E8 (milk fat globule epidermal growth factor 8), integrin αvβ3 and LIF (leukemia inhibitory factor) appear to play an important role. Furthermore, women with endometriosis and infertility may have in their implantation process the key to achieve pregnancy. Objectives: To investigate the role of MFG-E8 and its receptor integrin αvβ3 in the attachment of trophoblast cells to the endometrial epithelium, in an in vitro model. To compare endometrial expression of MFG-E8, integrin αvβ3 and LIF between fertile patients and patients with endometriosis and infertility during the window of implantation. Methods: In our first assay, by using a well-differentiated endometrial adenocarcinoma cell line (Ishikawa cells) and choriocarcinoma human trophoblast cells (Jar cells), an in vitro model mimicking human implantation was established. To investigate the impact of blocking MFG-E8 and integrin αvβ3, the cell lines were pretreated with antibodies against those proteins at different concentrations before the attachment assay. Moreover, to compare endometrial expression of MFG-E8, integrin αvβ3 and LIF, endometrial biopsies were performed during the window of implantation (LH+7 to LH+10) with the Pipelle catheter. The samples were submitted immunochemistry, and analyzed with HSCORE. Results: Pretreatment of Ishikawa cells with anti-MFG-E8 antibody caused a dosedependent and significant inhibition of attachment is our in vitro assay. On the other hand, pretreatment of Jar spheroids did not result in a significant effect on the attachment rate. Pretreatment of Ishikawa cells as well as Jar spheroids with anti-integrin avb3 antibodies resulted in a dose-dependent, significant inhibition of attachment. The immunochemistry analysis of the endometrial biopsies performed during the window of implantation showed increased MFG-E8 expression in patients with endometriosis and infertility. Moreover, there was lower LIF expression in the study group. Conclusion: This study showed that blocking MFG-E8 and its receptor integrin αvβ3 in Ishikawa cells diminishes Jar spheroid attachment in an in vitro model. Moreover, blocking integrin αvβ3 in the trophoblastic cells also diminished their attachment to the Ishikawa monolayer. Nevertheless, when we studied the endometrium of patients with endometriosis and infertility, we saw an increased expression of MFG-E8 and decreased expression of LIF during the window of implantation.

Base teórica: O processo de implantação do embrião no ser humano é extremamente complexo e, ao mesmo tempo, essencial para que a mulher possa engravidar. Neste processo, em que o endométrio precisa sofrer uma série de mudanças para tornar-se receptivo, a adequada expressão de MFG-E8 (milk fat globule epidermal growth factor 8), seu receptor a integrina αvβ3 e LIF (leukemia inhibitory factor) parecem ter um papel importante. Além do mais, mulheres com infertilidade e endometriose podem apresentar a falha de implantação como uma grande barreira para obter seu sucesso terapêutico. Objetivos: Avaliar o papel de MFG-E8 e do seu receptor integrina αvβ3 em um modelo de implantação in vitro com uma linhagem celular trofoblástica e outra de epitélio endometrial. Comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio de pacientes férteis e inférteis com endometriose durante a janela de implantação. Métodos: No primeiro ensaio, utilizando-se uma linhagem celular bem diferenciada de adenocarcinoma de endométrio (células Ishikawa) e uma linhagem de coriocarcinoma de trofoblasto, o modelo in vitro de implantação humana foi estabelecido. Para investigação do impacto do bloqueio de MFG-E8 e integrina αvβ3, ambas linhagens celulares foram pré-tratadas com anticorpos contra estas proteínas em diferente concentrações antes do ensaio de adesão. No ensaio subsequente, para comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio humano, foram realizadas biópsias no período da janela de implantação (LH+7 a LH+10) com cateter de Pipelle. As amostras foram submetidas a imunohistoquímica, e analisadas através do HSCORE. Resultados: Na avaliação in vitro observamos que as células Ishikawa pré-tratadas com anticorpo anti-MFG-E8 causaram diminuição da adesão das esferas Jar dose-dependente. Por outro lado, o pré-tratamento das esferas Jar não resultou em diminuição significativa da adesão. Pré-tratamento com anticorpos anti-integrina αvβ3, tanto de células Ishikawa como de esferas Jar, causaram inibição significativa, dose-dependente, da adesão das esferas. A análise imunohistoquímica das biópsias realizadas durante a janela de implantação mostrou uma expressão aumentada de MFG-E8 em pacientes com endometriose e infertilidade. Além do mais, houve expressão diminuída de LIF no grupo em estudo. Contudo, não houve diferença estatisticamente significativa na expressão de integrina αvβ3 entre os grupos em estudo. Conclusão: Este estudo demonstrou que, quando se bloqueia MFG-E8 ou seu receptor integrina αvβ3 em células Ishikawa em um modelo in vitro, ocorre uma diminuição de adesão das células Jar. Além do mais, bloqueando-se a integrina αvβ3 nas esferas Jar, também ocorre uma diminuição da adesão destas nas células Ishikawa. No entanto, quando estudamos o endométrio in vivo de pacientes com endometriose e infertilidade, encontramos a expressão aumentada de MFG-E8 e diminuída de LIF durante a janela de implantação no endométrio. / Background: The human implantation process is very complex and, at the same time, it is essential for women to achieve pregnancy. In this process, where the human endometrium must go through a lot of changes in order to become receptive, an adequate expression of MFG-E8 (milk fat globule epidermal growth factor 8), integrin αvβ3 and LIF (leukemia inhibitory factor) appear to play an important role. Furthermore, women with endometriosis and infertility may have in their implantation process the key to achieve pregnancy. Objectives: To investigate the role of MFG-E8 and its receptor integrin αvβ3 in the attachment of trophoblast cells to the endometrial epithelium, in an in vitro model. To compare endometrial expression of MFG-E8, integrin αvβ3 and LIF between fertile patients and patients with endometriosis and infertility during the window of implantation. Methods: In our first assay, by using a well-differentiated endometrial adenocarcinoma cell line (Ishikawa cells) and choriocarcinoma human trophoblast cells (Jar cells), an in vitro model mimicking human implantation was established. To investigate the impact of blocking MFG-E8 and integrin αvβ3, the cell lines were pretreated with antibodies against those proteins at different concentrations before the attachment assay. Moreover, to compare endometrial expression of MFG-E8, integrin αvβ3 and LIF, endometrial biopsies were performed during the window of implantation (LH+7 to LH+10) with the Pipelle catheter. The samples were submitted immunochemistry, and analyzed with HSCORE. Results: Pretreatment of Ishikawa cells with anti-MFG-E8 antibody caused a dosedependent and significant inhibition of attachment is our in vitro assay. On the other hand, pretreatment of Jar spheroids did not result in a significant effect on the attachment rate. Pretreatment of Ishikawa cells as well as Jar spheroids with anti-integrin avb3 antibodies resulted in a dose-dependent, significant inhibition of attachment. The immunochemistry analysis of the endometrial biopsies performed during the window of implantation showed increased MFG-E8 expression in patients with endometriosis and infertility. Moreover, there was lower LIF expression in the study group. Conclusion: This study showed that blocking MFG-E8 and its receptor integrin αvβ3 in Ishikawa cells diminishes Jar spheroid attachment in an in vitro model. Moreover, blocking integrin αvβ3 in the trophoblastic cells also diminished their attachment to the Ishikawa monolayer. Nevertheless, when we studied the endometrium of patients with endometriosis and infertility, we saw an increased expression of MFG-E8 and decreased expression of LIF during the window of implantation.

Base teórica: O processo de implantação do embrião no ser humano é extremamente complexo e, ao mesmo tempo, essencial para que a mulher possa engravidar. Neste processo, em que o endométrio precisa sofrer uma série de mudanças para tornar-se receptivo, a adequada expressão de MFG-E8 (milk fat globule epidermal growth factor 8), seu receptor a integrina αvβ3 e LIF (leukemia inhibitory factor) parecem ter um papel importante. Além do mais, mulheres com infertilidade e endometriose podem apresentar a falha de implantação como uma grande barreira para obter seu sucesso terapêutico. Objetivos: Avaliar o papel de MFG-E8 e do seu receptor integrina αvβ3 em um modelo de implantação in vitro com uma linhagem celular trofoblástica e outra de epitélio endometrial. Comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio de pacientes férteis e inférteis com endometriose durante a janela de implantação. Métodos: No primeiro ensaio, utilizando-se uma linhagem celular bem diferenciada de adenocarcinoma de endométrio (células Ishikawa) e uma linhagem de coriocarcinoma de trofoblasto, o modelo in vitro de implantação humana foi estabelecido. Para investigação do impacto do bloqueio de MFG-E8 e integrina αvβ3, ambas linhagens celulares foram pré-tratadas com anticorpos contra estas proteínas em diferente concentrações antes do ensaio de adesão. No ensaio subsequente, para comparar a expressão de MFG-E8, de integrina αvβ3 e de LIF no endométrio humano, foram realizadas biópsias no período da janela de implantação (LH+7 a LH+10) com cateter de Pipelle. As amostras foram submetidas a imunohistoquímica, e analisadas através do HSCORE. Resultados: Na avaliação in vitro observamos que as células Ishikawa pré-tratadas com anticorpo anti-MFG-E8 causaram diminuição da adesão das esferas Jar dose-dependente. Por outro lado, o pré-tratamento das esferas Jar não resultou em diminuição significativa da adesão. Pré-tratamento com anticorpos anti-integrina αvβ3, tanto de células Ishikawa como de esferas Jar, causaram inibição significativa, dose-dependente, da adesão das esferas. A análise imunohistoquímica das biópsias realizadas durante a janela de implantação mostrou uma expressão aumentada de MFG-E8 em pacientes com endometriose e infertilidade. Além do mais, houve expressão diminuída de LIF no grupo em estudo. Contudo, não houve diferença estatisticamente significativa na expressão de integrina αvβ3 entre os grupos em estudo. Conclusão: Este estudo demonstrou que, quando se bloqueia MFG-E8 ou seu receptor integrina αvβ3 em células Ishikawa em um modelo in vitro, ocorre uma diminuição de adesão das células Jar. Além do mais, bloqueando-se a integrina αvβ3 nas esferas Jar, também ocorre uma diminuição da adesão destas nas células Ishikawa. No entanto, quando estudamos o endométrio in vivo de pacientes com endometriose e infertilidade, encontramos a expressão aumentada de MFG-E8 e diminuída de LIF durante a janela de implantação no endométrio. / Background: The human implantation process is very complex and, at the same time, it is essential for women to achieve pregnancy. In this process, where the human endometrium must go through a lot of changes in order to become receptive, an adequate expression of MFG-E8 (milk fat globule epidermal growth factor 8), integrin αvβ3 and LIF (leukemia inhibitory factor) appear to play an important role. Furthermore, women with endometriosis and infertility may have in their implantation process the key to achieve pregnancy. Objectives: To investigate the role of MFG-E8 and its receptor integrin αvβ3 in the attachment of trophoblast cells to the endometrial epithelium, in an in vitro model. To compare endometrial expression of MFG-E8, integrin αvβ3 and LIF between fertile patients and patients with endometriosis and infertility during the window of implantation. Methods: In our first assay, by using a well-differentiated endometrial adenocarcinoma cell line (Ishikawa cells) and choriocarcinoma human trophoblast cells (Jar cells), an in vitro model mimicking human implantation was established. To investigate the impact of blocking MFG-E8 and integrin αvβ3, the cell lines were pretreated with antibodies against those proteins at different concentrations before the attachment assay. Moreover, to compare endometrial expression of MFG-E8, integrin αvβ3 and LIF, endometrial biopsies were performed during the window of implantation (LH+7 to LH+10) with the Pipelle catheter. The samples were submitted immunochemistry, and analyzed with HSCORE. Results: Pretreatment of Ishikawa cells with anti-MFG-E8 antibody caused a dosedependent and significant inhibition of attachment is our in vitro assay. On the other hand, pretreatment of Jar spheroids did not result in a significant effect on the attachment rate. Pretreatment of Ishikawa cells as well as Jar spheroids with anti-integrin avb3 antibodies resulted in a dose-dependent, significant inhibition of attachment. The immunochemistry analysis of the endometrial biopsies performed during the window of implantation showed increased MFG-E8 expression in patients with endometriosis and infertility. Moreover, there was lower LIF expression in the study group. Conclusion: This study showed that blocking MFG-E8 and its receptor integrin αvβ3 in Ishikawa cells diminishes Jar spheroid attachment in an in vitro model. Moreover, blocking integrin αvβ3 in the trophoblastic cells also diminished their attachment to the Ishikawa monolayer. Nevertheless, when we studied the endometrium of patients with endometriosis and infertility, we saw an increased expression of MFG-E8 and decreased expression of LIF during the window of implantation.

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No description available.