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Method Development for Corrosion Testing of Carbon Steel and Ni-based Alloy Coatings Exposed to Gas Hydrate Formation EnvironmentsOzigagu, Christopher E. 08 1900 (has links)
Gas hydrate formation and corrosion can cause serious safety and flow assurance problems in subsea environments. One aspect that has been given less attention is the corrosion behavior of materials in gas hydrate formation environment (GHFE). This work introduces a new technique/method for corrosion testing of materials exposed to low temperatures GHFEs. This technique allows pH monitoring, and control of test conditions like temperature. In this work, GHFE is defined as an environment that includes water, methanol and its degraded products in the presence of corrosive agents like CO2 and chloride salt at gas hydrate formation temperatures (GHFT). After 20 hrs immersion in CO2-saturated salinity environment at GHFT, as-deposited Ni-Mo alloy coating has the highest corrosion resistance of 33.28 kΩ cm2. The corrosion resistance dropped to 14.36 kΩ cm2 and 11.11 kΩ cm2 in the sweet low-salinity and sweet high-salinity test solutions respectively. The combined results of SEM/EDX showed that the Ni-Mo coating oxide layer broke down quicker in sweet high-salinity environment than sweet low-salinity environment. When carbon steel was immersed in a CO2-saturated high salinity environment at GHFT, there was slight overall change in corrosion rate (CR) as salt concentration increase from 3 wt% to 25 wt%. In degraded methanol environment, methanol showed an inhibitive effect on the corrosion of carbon steel. Higher methanol content (up to 50 vol. %) increased the corrosion rate of carbon steel at gas hydrate formation temperature, however, the corrosion rates were lower with methanol contents between 10 to 20 vol%.
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Investigating the Instrumentational Components of Laser Electrospray Mass Spectrometry: Analytical Method Development and ApplicationsParise, Rachel, 0000-0002-6796-1573 January 2022 (has links)
Analytical method validation is the process of establishing that an analytical technique is applicable for a proposed objective. Early in the method development of a new analytical technique an understanding of the instrumental components and procedures is elaborated through scientifically based optimization. The optimization experiments are used to define the operational parameters that yield the maximum performance by the analytical technique for the target analyte before commencing validation studies. This dissertation details method development through experimental investigations instrumental components of LEMS (substrate, laser parameters, and electrospray source conditions). Each instrumental component has a number of induvial parameters which are optimized to yield the maximum laser electrospray mass spectrometry (LEMS) signal intensity for a given analytical problem. LEMS uses a nonresonant, femtosecond (fs) laser to ablate analytes from a surface. Those ablated analytes are then captured by a perpendicular electrospray, ionized, and desolvated to produce ions which travel into the inlet of the mass spectrometer for analysis. Each element of the LEMS experimental setup works in a complementary fashion to generate a mass spectral signal which have specific optimization steps that can dramatically impact the data that can be acquired. The results of the optimization for each instrumental component will then be applied to preliminary method development experiments for the analysis of pharmaceutical compounds from complex formulations biomarker discovery for mice afflicted with a traumatic brain injury.The effect of the laser pulse duration on the ablation mechanism and amount of laser induced conformational changes of aqueous myoglobin was investigated using 55 fs, 56 picosecond (ps), and 10 nanosecond (ns) pulses and laser pulse energies from 0.05 to 1.6 mJ. It was found that the optical properties of the substrates (stainless-steel and quartz) and laser intensity regimes accessible by each pulse duration determined the amount of myoglobin ablated and subsequent mass spectral signal intensity. Laser ablation of myoglobin from both substrates using all laser pulse energies was observed for the 55 fs pulse while the 10 ns pulse required minimum pulse energies of 0.4 and 1.2 mJ for ablation of myoglobin to occur from stainless-steel and quartz, respectively. As the pulse duration increases, thermal processes increase which dictated the relative amount of protein unfolding, number of phosphate adducts, and degree of solvent adduction.
Many of the common laser electrospray ionization (ESI) hybrid techniques employ ns pulse durations. However, the amount of ablated myoglobin originating from a ns pulse was observed to be dependent on the amount of energy that was absorbed by the substrate or sample. Experiments to increase the signal intensity while implementing ns laser electrospray mass spectrometry (ns-LEMS) were performed by exploiting the optical properties of nanomaterials as a potential matrix for desorption and detection of myoglobin. To estimate the contribution of the surface plasmon resonance (SPR) to the desorption of myoglobin under the different pulse duration regimes, the addition of an aqueous gold nanostar (GNS) matrix was implemented. GNSs have a SPR maximum of ~750 nm which overlaps strongly with the 780 nm laser wavelength. Gold nanospheres, which have a SPR of ~530 nm, have an absorption overlap 25 times less than that of the nanostars with the 785 nm laser light and therefore were chosen as a control gold nanoparticle matrix. It was observed that protein mixed with solution phase GNSs improved the laser ablation and consequent mass spectral signal intensity of the protein in comparison to both the nanosphere addition and ablation from quartz without nanomaterial addition for the 55 fs, 56 ps, and 10 ns pulses.
This dissertation also extends to an investigation of the electrospray source and the roles that the nebulizing gas pressure, electrospray solution flow rate, and needle protrusion from the emitter sheath effects the electrospray analyte signal and stability. Interactions between the electrospray droplets and nebulizing gas were elucidated using an ablation chamber in which laser ablated analytes were carried via the nebulizing gas flow through the nebulizer sheath to interact with the electrospray Taylor cone, jet, and subsequent droplets. The signal intensity and relative standard deviation (RSD) of an infused Victoria blue solution was used to assess conventional ESI optimization experiments while a mixture of Gly-Gly-His, lactose, adenosine, and vitamin B12 was laser ablated within the ablation chamber for the optimization of the remote ablation device. It was found that a needle protrusion flush with the nebulizing sheath wall, 9 psi nebulizing gas pressure, and 9 µL/min ESI flow rate yielded the highest signal intensity for low and high mass analytes when utilizing the ablation chamber. However, the conventional ESI signal and stability was maximized using a needle protrusion of 0.6 mm from the sheath, 18 psi nebulizing gas pressure, and 9 µL/ min ESI flow rate.
The last two chapters describe collaborative efforts with GlaxoSmithKline (GSK) and Temple University’s Lewis Katz School of Medicine with the application of LEMS to real world problems. The first of these chapters explores the preliminary method development results for sampling protocols of LEMS in a pathway to measuring the active ingredient in a formulation when differences in concentration are a percent or less for GSK. The results from the method development and optimization experiments in the previous chapters were applied to the GSK pharmaceutical manufacturing paradigm to test product quality in-line and in real-time instead of testing in a lab at the end of the manufacturing process. The LEMS sampling protocols involved ablation of either powder, compressed form, or solution containing powder using laser ablation. The ablated material was then entrained in an electrospray aerosol and transferred into a mass spectrometer for quantitative measurement of the molecules making up the powder, pill, or solution. Measurement time was on the order of seconds so that thousands of samples can be potentially measured in an hour. Future prospective experiments include additional optimization of the solution phase and compressed form sampling methods and, ultimately, the method validation of LEMS for quantifying active ingredients in pharmaceutical formulations. The last chapter seeks to develop new methods to map all biomarkers in traumatic brain injury (TBI) through mass spectrometry imaging (MSI), serum analysis, and protein derivatization assays. In this work, the Ramirez laboratory employs the controlled cortical impact model of experimental TBI in mice, harvests the brain (post injury) and prepares sections for analytical analysis. TBI is a complex injury involving multiple physiological and biochemical alterations to tissue. The potentially thousands of relevant biomarkers spread over a volume of thousands of mm3 makes the spatially resolved chemical analysis of brain a big data problem to which principal component analysis is applied. / Chemistry
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Method development and screening of extractable organofluorine (EOF) and targeted PFAS analysis in food packaging materialsLarsson, Nora January 2022 (has links)
Per- and polyfluoroalkyl substances (PFAS) have been manufactured and used in differentapplications for several decades, including food packaging materials. During the last 20 yearsthese compounds have been acknowledged as hazardous for humans and the environment, anddifferent regulations on PFAS have been established on both national and international levels.Companies started to phase-out long-chain PFAS, including both PFOA and PFOS, around 20years ago. Since PFAS are persistent, this cause concerns both for our health and theenvironment, as well as possible PFAS contamination in new products due to the recycling ofmaterials. The aim of this study was to find an effective method to extract PFAS from differentfood packaging materials; analyze the samples for their extractable organofluorine (EOF)content using combustion ion chromatography; as well as analyze targeted PFAS in the samplesusing ultra-high performance liquid chromatography tandem mass spectrometry. The findingsof this study suggest that none of the selected samples had EOF contents above the Danishindicator value of 20 mg/kg dw TOF set to determine whether PFAS has been intentionallyadded to a material, and that only two samples exceeded the limit of detection for EOF. Atakeaway bowl made out of 100% sugarcane contained the highest EOF content while the outerpackaging of a cereal box contained the second highest EOF. Both PFOA and PFOS, alongwith other long-chain PFAS were detected in a majority of the samples. The lowest total PFASconcentrations when analyzing for targeted PFAS was detected in the sugarcane take awaybowl. The highest total PFAS concentration was detected in an egg carton, followed by theouter packaging of a cereal box (same as above) and the outer box of a waffle mix. The targetedPFAS was detected in almost all samples, with PFNA and 6:2 diPAP being the most frequentlydetected PFAS. PFCAs, PFSAs, FTSAs, FOSAAs and PAPs were detected in a majority of thesamples. The highest concentrations were measured for diSAmPAP in a majority of thesamples. Mass balance calculations of the sugarcane bowl showed that the targeted PFAS onlyaccounted for 0.04% of the extractable organofluorine content. In conclusion, none of thesamples displayed EOF contents higher than the Danish indicator value, suggesting that noneof the samples were intentionally treated with PFAS. However, targeted PFAS analysis of thesesamples showed that they still contain PFAS, that could be further recycled along with therecycling of paper and board food packaging materials. Considering the persistence of PFASand that these compounds can remain in the recycling chain, with the risk of also being releasedinto the environment, it is of importance that PFAS is not introduced in any of the stages in apaper or board containers life cycle.
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Microscopic Sampling of Dentine and Bone Collagen: Development of Sampling Methods for Carbon and Nitrogen Isotope AnalysisCurtis, Mandi J. January 2021 (has links)
Sampling methods for dentine and bone collagen have been evolving for several
decades. Incremental dentine collagen sampling and bone collagen sampling
have been limited by the available technology throughout that time. As the
technology for isotope ratio mass spectrometry analysis improves, the sampling
methods should improve as well. This research focused on developing a new
incremental dentine collagen sampling method and bone collagen microsampling
method for stable isotope analysis. This research aimed to increase the
temporal resolution of incremental dentine collagen sampling and provided
sequential collagen sampling from bone collagen for stable carbon and nitrogen
isotope analysis while limiting the destructive nature of bioarchaeological
analysis. It was determined that the temporal resolution for incremental analysis
could be reduced to approximate three months, opposed to the nine months
found in other sampling methods. It was also determined that detailed isotopic
data could be obtained from bone collagen when sampling the microstructures.
The increased amount of isotopic data from the bone collagen was an
improvement on the commonly used bulk collagen sampling. This research can
be utilised to answer several of the questions that archaeologists have been
asking about past populations. Isotopic analysis using the methods developed in
the research can provide a more detailed observation of the diet and health of past populations.
In addition, the developed methods for bone and dentine collagen reduced the amount of tissue
subjected to destructive analysis.
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Chronic Kidney Disease: Vitamin D Treatment Regimens and Novel Assay Development for Kidney and Cardiovascular Function BiomarkersEl-Khoury, Joe M. 02 August 2012 (has links)
No description available.
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Method development : follow liquid distribution in real time / Metodutveckling för vätskespridningNdahimana, Joice, Issa, Tammar January 2017 (has links)
Continuous development and improvement of the modern disposable diaper is crucial for the optimization of product performance. Several methods are used for evaluation and improvements to sustain high quality diapers being produced. The aim of this thesis was to develop a new test method that follows liquid distribution in real time by combining two pre-existing measurement systems. Rewet is the amount of liquid that returns to the surface of diapers when subjected to pressure. Distribution of absorption material is examined by exposing the product core to radiation. These two measurement systems don’t convey anything about the course of the liquid in the diaper when tested separately. This method development is meant to be beneficial for research and development purposes at SCA, working as a complement to the pre-existing methods being used in the laboratory. The following questions are of interest: • Can the rewet test method be performed on a baby diaper while simultaneously exposing the product core to radiation so the course of the liquid can be followed in real time? • Is the liquid distribution (wet area) affected by different product compositions e.g. SAP or thickness? By modifying the current methods, rewet can be performed inside the x-ray equipment while studying the consistency of absorption material and following the liquid behavior in the product core. The developed method was verified by testing on handmade products with different compositions. The developed method’s rewet value has proved to be equivalent to the one tested outside, showing no significant difference between the two.
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Kvantitativ analys av organiska syror i kylvätska / Quantitative analysis of organic acids in engine coolantHenriksson, Emma, Holm, Martin January 2017 (has links)
Volvo Cars är ett välkänt företag som säljer bilar över hela världen. Idag skickar Volvo Cars sin kylvätska till leverantörer för analys. Processen är komplicerad och tar mycket tid. Det finns ett intresse hos Volvo Cars att själva kunna analysera kylvätskan. För att kunna göra detta krävs det att en metod som de kan använda för att analysera kylvätskan utvecklas. Examensarbetet syftar till att utveckla en metod som gör det möjligt att analysera koncentrationen av organiska syror i Volvos kylvätska. Analysen ska göras med hjälp av en High Performance Liquid Chromatography - HPLC. De organiska syrorna är inhibitorer som skyddar material i motorn från korrosion när det kommer i kontakt med kylvätskan. Metoden utvecklas i flera steg, det är viktigt att veta hur olika organiska syror kan analyseras med en HPLC. HPLC-analyser är mycket beroende av de intrumentella inställningarna. Inställningarna som ändrar när metoden utvecklas är pH, typ av kolonn, våglängd på detektorn, flödeshastighet i kolonnen, injektionsvolymen, sammansättning av eluent (lösningsmedel) och analystid. Kalibreringskurvor konstrueras för att sedan kunna användas i fortsatta studier. Tre av fem organiska syror som skulle analyseras var möjliga att analysera med två olika metoder. Den enda skillnaden mellan metoderna var våglängden på detektorn. En av de organiska syrorna hade en mer linjär kalibreringskurva vid en högre våglängd. / Volvo Cars is a well-known company and they are selling their cars all over the world. Today, Volvo Cars send their engine coolant to the supplier of engine coolant for analysis. This process is complicated and takes a lot of time. It is in the interest of Volvo Cars to be able to analyze the engine coolant themselves. In order to do that, a method where they can analyze the engine coolant must be developed. This exam work aim to develop a method where it is possible to analyze the concentration of organic acids in Volvo´s engine coolant with a High Performance Liquid Chromatography - HPLC. The organic acids are inhibitors that protect the materials in the engine from corrosion when in contact with the engine coolant. The method is developed in several steps. First it is important to know how different organic acids could be analyzed with an HPLC. HPLC-analysis is very dependent of the instrumental parameters. The parameters you change when developing a method are pH, kind of column, wavelength of the detector, kind of detector, flow rate in the column, injections volume, composition of the eluent (solvent) and, analysis time. Calibration curves are created and could be used as a reference in further analysis. Three of the five organic acids that were supposed to be analyzed were possible to analyze. Three organic acids were analyzed with one method and the two remaining organic acids with another method. The only difference between the methods is the wavelengths of the detector.
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Desenvolvimento de métodos e instrumentação para amostragem e determinação de algumas espécies relacionadas aos processos de acidificação da atmosfera / The development of methods and instrumentation for sampling and determination of certain species related to atmospheric acidification processesRocha, Flavio Roberto 27 June 2003 (has links)
A atmosfera, ao lado dos principais gases que a compõe, apresenta em menores concentrações milhares de compostos químicos (orgânicos e inorgânicos) distribuídos nas fases líquidas e gasosa ou no material particulado. Quando esses compostos encontrados no ar apresentam níveis de concentração que os tornam impróprios ou nocivos à saúde humana, aos animais ou vegetais e danosos aos materiais, são considerados poluentes atmosféricos. Neste trabalho, enfatizou-se o estabelecimento de métodos alternativos, eficientes e práticos, para a amostragem de várias espécies que participam dos processos de acidificação da atmosfera, assim corno o desenvolvimento de métodos analíticos baseados em técnicas eletroanalíticas em fluxo como a amperometria e a eletroforese capilar com detecção condutométrica sem contato. Devido a algumas limitações das técnicas de amostragem, explorou-se a alternativa de recorrer a tubos capilares com paredes microporosas, preenchidos com solução adequada à absorção das espécies em pauta, após sua difusão através dos poros da membrana hidrófoba. Assim, construiu-se um coletor por difusão utilizando-se tubo de Teflon®, dentro do qual foi introduzido um feixe de tubos capilares porosos de polipropileno. A união desta técnica de amostragem com a determinação seletiva e quantitativa dos analitos por eletroforese capilar com detecção condutométrica (CE-CCD) possibilitou o desenvolvimento de métodos completos para as seguintes espécies: CH2O coletado em água deionizada, à freqüência de 1 amostra por hora, seguido de derivatização com HSO3- para determinação de fonnaldeído na forma de hidroximetanossulfonato (HMS); HCOOH e H3C2OOH- com o mesmo procedimento de coleta e separação por CE-CCD aplicado na detenninação de CH2O na forma de HMS; e NH3 - coletado em solução de HCl e determinado na forma de NH4+ por CE-CCD. Outra espécie de interesse ambiental é o H2O2, por participar de várias reações de oxidação tanto na fase gasosa corno na fase líquida da atmosfera, contribuindo assim para a acidez da atmosfera. A detenninação analítica do H2O2 foi feita por método FIA amperométrico com eletrodo de gota pendente de mercúrio, adaptando-se célula eletroquímica estacionária ao trabalho em fluxo. Duas formas de coleta de H2O2 na fase gasosa foram desenvolvidas e comparadas: . coleta por difusão - com fluxo de água deionizada pelos feixe de filamentos capilares; nesta aplicação, o feixe foi conectado diretamente à alça de amostragem do injetor, proporcionando determinações on-line\". . amostragem criogênica em dispositivo \"passivo\" - aproveitando o fato conhecido de que a razão H2O:H2O2 da fase gasosa se mantém praticamente inalterada na fase sólida (gelo coletado). Além das determinações de H2O2 na fase gasosa, o método FIA-Amperométrico foi utilizado, em trabalhos realizados em parceria com pesquisadores do IPEN, para determinação dessa espécie em efluentes e água de cultivo do microcrustáceo Daphnia similis após serem irradiados com feixes de elétrons. Paralelamente às pesquisas relacionadas a espécies gasosas, desenvolveu-se metodologia para a determinação de cátions e ânions majoritários em água de chuva, recorrendo à CE-CCD, de modo a oferecer uma alternativa à consagrada técnica da cromatografia de íons, demorada e onerosa. Os estudos iniciais da composição iônica da chuva foram feitos com coletas de água de chuva efetuadas no período de Abril/97 a Março/98. Nesse conjunto de amostras determinou-se as concentrações dos cátions (NH4+, Ca2+, K+ e Na+) e dos ânions (NO3-, SO42- e Cl-), além das usuais medições de pH e condutividade. A Eletroforese Capilar mostrou-se particularmente tàvorável para a determinação dos íons majoritários em água de chuva. Embora fugindo da área ambiental, desenvolveu-se metodologia para determinação de espécies de S(IV) em amostras de vinho, a partir de algumas adaptações de método amperométrico em fluxo desenvolvido no mestrado para análise de sulfito e HMS em água de chuva. Assim, desenvolveu-se três sistemas FIA-Amperométrico com eletrodo de gota pendente de mercúrio distintos, os quais foram utilizados para determinação de HSO3- livre e adutado (na forma de hidroxialcanossulfonatos) e SO2, com auxílio de uma unidade de difusão gasosa. / Alongside with its main components, the atmosphere contains trace amounts of thousands of chemical compounds (organic and inorganic) distributed in the liquid and gaseous phases, as well as in the particulate matter. These species can be considered pollutants when they are encountered at levels capable of generating adverse effects to humans, animals, plants or materials. The aim of this work was to establish alternative, efficient and practical methods for the sampling of several species encountered in the gaseous phase, as well as to develop analytical methods based on electroanalytical flow techniques, such as amperometry and capillary electrophoresis with contactless conductometric detection (CE-CCD). Due to some limitations in the existing sampling techniques, an altemative method based on the diffusion of the analytes through the microporous hydrophobic walls of capillary tube filled with an appropriate absorbent solution, was investigated. The collecting device was assembled using a Teflon® tube wherein a bundle of porous capillary polypropylene tubes was introduced. The coupling of this sampling technique with the selective and quantitative determination of the species by capillary electrophoresis with contactless conductometric detection (CE-CCD) enabled the development of complete analytical protocols for the following species: i) CH2O - collected in deionized water at a frequency of 1 sample/h and derivatized with HSO3- for its determination as hydroxymethanesulfonate (HMS); ii) HCOOH and H3COOH - collected using the same sampling procedure and quantified upon separation by CE-CCD; and iii) NH3 - collected in a HCl solution and deterrnined as NH4+ form. Another species of environmental interest is H2O2, which contributes to the acidity of the atmosphere on account of its involvement in some oxidation process both in the gaseous and liquid phases. The deterrnination of the H2O2 Was carried out using a FIA amperometric method at the hanging mercury drop electrode, in a batch electrochemical cell adapted to function under tlowing conditions. Two sampling procedures for H2O2 in the gaseous phase were developed and compared: . collection by diffusion - from the air into a flow of deionized water within the bundle of capillary filaments, which were, in tum, connected to the sample loop in order to allow on-line deterrninations. · cryogenic, with a \"passive\" sampler - based on the well-known fact that the H2O:H2O2 ratio in the gaseous phase is practically maintained in the solid phase. In addition to these determinations in the gaseous phase and in a partnership with researchers of the IPEN, the FIA-Amperometric method was used for the quantification of H2O2 in effluent and in cultivation water of the microcrustacean Daphnia Similis after irradiation by MeV electron beams. In parallel to the related research, a methodology for the CE-CCD determination of majority cations and anions in rain water was developed. This was proposed as an altemarive method to well-established ion chromatography techniques. Initial studies on the ionic composition of rain were conducted on samples collected between April/97 and March/98, using an automatic collector previously developed. In this set of samples, the concentrations of cations (NH4+, Ca2+, K+ e Na+) and anions (NO3-, SO42- e Cl-) were determined, together with the usual measurements of pH and conductivity. Capillary electrophoresis tumed out to be particularly suitable for the determination of ions in rain water. Although strictly not environrnental in kind, a methodology for determination of S(IV) species in wine samples was implemented by adjusting a previously-developed flow-amperometric method for the analysis of sulfite and HMS in rain water. For this purpose, three distinct FIA-Amperometric systems using a gas diffusion device and the hanging mercury drop electrode were designed, assembled and used for the determination of HSO3- in the free and bound forms (as hydroxyaIkanesulfonates) and SO2.
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Characterisation of the tumour microenvironment in ovarian cancerJiménez Sánchez, Alejandro January 2019 (has links)
The tumour microenvironment comprises the non-cancerous cells present in the tumour mass (fibroblasts, endothelial, and immune cells), as well as signalling molecules and extracellular matrix. Tumour growth, invasion, metastasis, and response to therapy are influenced by the tumour microenvironment. Therefore, characterising the cellular and molecular components of the tumour microenvironment, and understanding how they influence tumour progression, represent a crucial aim for the success of cancer therapies. High-grade serous ovarian cancer provides an excellent opportunity to systematically study the tumour microenvironment due to its clinical presentation of advanced disseminated disease and debulking surgery being standard of care. This thesis first presents a case report of a long-term survivor (>10 years) of metastatic high-grade serous ovarian cancer who exhibited concomitant regression/progression of the metastatic lesions (5 samples). We found that progressing metastases were characterized by immune cell exclusion, whereas regressing metastases were infiltrated by CD8+ and CD4+ T cells. Through a T cell - neoepitope challenge assay we demonstrated that pre- dicted neoepitopes were recognised by the CD8+ T cells obtained from blood drawn from the patient, suggesting that regressing tumours were subjected to immune attack. Immune excluded tumours presented a higher expression of immunosuppressive Wnt signalling, while infiltrated tumours showed a higher expression of the T cell chemoattractant CXCL9 and evidence of immunoediting. These findings suggest that multiple distinct tumour immune microenvironments can co-exist within a single individual and may explain in part the hetero- geneous fates of metastatic lesions often observed in the clinic post-therapy. Second, this thesis explores the prevalence of intra-patient tumour microenvironment het- erogeneity in high-grade serous ovarian cancer at diagnosis (38 samples from 8 patients), as well as the effect of chemotherapy on the tumour microenvironment (80 paired samples from 40 patients). Whole transcriptome analysis and image-based quantification of T cells from treatment-naive tumours revealed highly prevalent variability in immune signalling and distinct immune microenvironments co-existing within the same individuals at diagnosis. ConsensusTME, a method that generates consensus immune and stromal cell gene signatures by intersecting state-of-the-art deconvolution methods that predict immune cell populations using bulk RNA data was developed. ConsensusTME improved accuracy and sensitivity of T cell and leukocyte deconvolutions in ovarian cancer samples. As previously observed in the case report, Wnt signalling expression positively correlated with immune cell exclusion. To evaluate the effect of chemotherapy on the tumour microenvironment, we compared site-matched and site-unmatched tumours before and after neoadjuvant chemotherapy. Site- matched samples showed increased cytotoxic immune activation and oligoclonal expansion of T cells after chemotherapy, unlike site-unmatched samples where heterogeneity could not be accounted for. In addition, low levels of immune activation pre-chemotherapy were found to be correlated with immune activation upon chemotherapy treatment. These results cor- roborate that the tumour-immune interface in advanced high-grade serous ovarian cancer is intrinsically heterogeneous, and that chemotherapy induces an immunogenic effect mediated by cytotoxic cells. Finally, the different deconvolution methods were benchmarked along with ConsensusTME in a pan-cancer setting by comparing deconvolution scores to DNA-based purity scores, leukocyte methylation data, and tumour infiltrating lymphocyte counts from image analysis. In so far as it has been benchmarked, unlike the other methods, ConsensusTME performs consistently among the top three methods across cancer-related benchmarks. Additionally, ConsensusTME provides a dynamic and evolvable framework that can integrate newer de- convolution tools and benchmark their performance against itself, thus generating an ever updated version. Overall, this thesis presents a systematic characterisation of the tumour microenvironment of high grade serous ovarian cancer in treatment-naive and chemotherapy treated samples, and puts forward the development of an integrative computational method for the systematic analysis of the tumour microenvironment of different tumour types using bulk RNA data.
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DFM/A-metod för integrerade strukturdelar i kolfiberkomposit : Vidareutveckling av metodik för SAAB Aerostructures / DFM/A method for integrated structures of carbon fiber reinforced plastic : Further development of methodology for SAAB AerostructuresJensen, Jonas, Nilsson, Sara January 2015 (has links)
Kolfiberkompositer är ett av de materialsom utvecklas snabbast just nu. Analogt med att materialet blir billigare och börjar användas i större utsträckning av flygindustrin utvecklas också tillverkningsmetoder för att följa framstegen. Hur material och tillverkningsmetoder sätter krav och påverkar en produkts utformning och prestanda kan vara svårt att definiera. I detta examensarbete har en Design for Manufacturing och Assembly (DFM/A)-metod utvecklats för att under hela produktutvecklingsprocessen kunna ta hänsyn till produktionsaspekter. DFM/Ametoden är framtagen åt Saab Aerostructures med hänsyn till de material som används, deras existerande produktionsprocesser och den produktutvecklingsprocess som finns på företaget. Utifrån litteratur- och fallstudier har en DFM/A-metod som kallas Metod 2015 (M2015) utvecklats. Metoden innehåller en arbetsprocess, konstruktionsriktlinjer samt stödjande DFM/Averktyg. Genom att i hela utvecklingsprocessen ta hänsyn till produktionsaspekter är detta arbetssätt anpassat för att underlätta utveckling av kolfiberkompositkomponenter på Saab. Utöver själva metoden i sig finns allt material som behövs för användning av M2015 sammanställt i en manual som i första hand riktar sig till konstruktören. Genom att skapa en bättre förståelse för produktionsaspekterna hos en konstruktion och tillhandahålla rätt verktyg kan DFM/A-metoden bidra till flera positiva effekter. Användandet av M2015 bör leda till produkter av kolfiberkomposit som är lättare att tillverka vilket i sin tur också bör minska onödiga kostnader, ge högre kvalitet och kortare ledtider. Införandet ställer dock också krav på Saab för att dessa målsättningar ska kunna uppnås. / Carbon fiber reinforced plastic (CFRP) is one of the fastest developing materials right now. Analogously to the material becoming cheaper and being used more widely in the aerospace industry the manufacturing methods have developed to follow the progress. How material and manufacturing method change the requirements and affect a product's design and performance can be hard to determine. This degree project has developed a Design for Manufacturing and Assembly (DFM/A) method to easier take into consideration the production process throughout the product development. The DFM/A method is developed for Saab Aerostructures and is based on their materials, production process and product development process. By studying literature and performing case studies a DFM/A method called Method 2015 (M2015) was developed. The method includes a work procedure, design guidelines and supporting DFM/A tools. By considering the production aspects throughout the development process this method of operation facilitate the development of CFRP products at Saab. In addition to the method itself the materials needed to use M2015 is compiled in a manual for the designer. By creating a better understanding of the production aspects of a design and providing the right tools the DFM/A method can contribute to several positive effects. The use of M2015 should lead to CFRP products that are easier to produce which in turn should minimize unnecessary costs, raise the quality and shorten lead times. However, the implementation of M2015 at Saab also creates demands to reach these targets
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