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Legal aspects of transmission of digital assets on death
Get PDFThis thesis explores the key issues surrounding the transmission of digital assets on death. To answer this primary research questions, the author first looks at the legal nature of digital assets, which are defined as any asset of personal or economic value online (capable of post-mortem transmission). She then analyses in depth the three most typical and widely used types of assets: virtual worlds, emails and social networks. In trying to reach decisions on the legal nature of digital assets, the thesis first looks for help to the institution of property. If an asset can be considered the property of the deceased user, then in most countries it forms part of an estate and transmits on death. The same goes for intellectual property (primarily copyright herein). If an asset cannot and should not be considered property, or protected by copyright, then arguably it cannot transmit on death. The thesis finds that email contents, virtual world items and social network contents are not and should not be considered as property. Some of this content can, however, be protected by copyright and thus is transmissible on death. If significant user interests and expectations exist in the transmission of digital assets on death, therefore, legislative action will be required in the areas of copyright and succession laws. The research demonstrates that some of the content, primarily information and personal data, is neither property nor protected by copyright. For this content, the analysis discusses some alternative legal institutions (breach of confidence, data protection) and argues that their protection can be extended to include the deceased users. The thesis thus introduces a novel phenomenon of post-mortem privacy, the protection of privacy interests of the deceased. It argues that this phenomenon merits a policy and legal account and submits that this concept should foster the user's autonomy and control, preventing the default transmission of digital assets on death. The thesis further looks at the allocation of ownership of assets through service providers' contracts, finding a contradictory approach of service providers regarding ownership and transmission of digital assets. These contracts usually curtail the users' autonomy and control over their assets in life and post-mortem. There have been some recent technological developments led by Google and Facebook, which enable an in-service transmission on the death of some of the content associated with these accounts. These solutions are not free from problems, and the thesis evaluates them and proposes some improvements. User's autonomy is the main underpinning value of the thesis and the basis for some tentative solutions suggested in the thesis.This thesis explores the key issues surrounding the transmission of digital assets on death. To answer this primary research questions, the author first looks at the legal nature of digital assets, which are defined as any asset of personal or economic value online (capable of post-mortem transmission). She then analyses in depth the three most typical and widely used types of assets: virtual worlds, emails and social networks. In trying to reach decisions on the legal nature of digital assets, the thesis first looks for help to the institution of property. If an asset can be considered the property of the deceased user, then in most countries it forms part of an estate and transmits on death. The same goes for intellectual property (primarily copyright herein). If an asset cannot and should not be considered property, or protected by copyright, then arguably it cannot transmit on death. The thesis finds that email contents, virtual world items and social network contents are not and should not be considered as property. Some of this content can, however, be protected by copyright and thus is transmissible on death. If significant user interests and expectations exist in the transmission of digital assets on death, therefore, legislative action will be required in the areas of copyright and succession laws. The research demonstrates that some of the content, primarily information and personal data, is neither property nor protected by copyright. For this content, the analysis discusses some alternative legal institutions (breach of confidence, data protection) and argues that their protection can be extended to include the deceased users. The thesis thus introduces a novel phenomenon of post-mortem privacy, the protection of privacy interests of the deceased. It argues that this phenomenon merits a policy and legal account and submits that this concept should foster the user's autonomy and control, preventing the default transmission of digital assets on death. The thesis further looks at the allocation of ownership of assets through service providers' contracts, finding a contradictory approach of service providers regarding ownership and transmission of digital assets. These contracts usually curtail the users' autonomy and control over their assets in life and post-mortem. There have been some recent technological developments led by Google and Facebook, which enable an in-service transmission on the death of some of the content associated with these accounts. These solutions are not free from problems, and the thesis evaluates them and proposes some improvements. User's autonomy is the main underpinning value of the thesis and the basis for some tentative solutions suggested in the thesis
"Doing" gender in a rural Scottish secondary school : a case study
Get PDFThis ethnographic case study examines how pupils' gendered identities are constructed in one rural secondary school in Scotland. It utilises the work of Michel Foucault and Judith Butler to provide theoretical insight into how and why pupils take up particular gendered positions in the school. Data collection is primarily by ethnographic observation, supported by semi-structured interviews. The findings highlight the discursive role of peer interactions in affecting how pupils shape their gendered identities, with boys seen to be more affected by peer influences than girls. Subject choices emerged as the strongest gender-related curricular theme; girls in the school appear somewhat bound by gender norms when making subject choices throughout their school career. Insights into how some pupils and teachers perceive the rural space as a masculine one also emerged in the data. Overt femininity was seen as very much at odds with the rural landscape, meaning that some girls find conflict in how they construct their feminine identity. The findings also suggest that teacher discourse can reinforce traditional constructs of masculinities and femininities, and that some teachers' understandings of gender rely on binary views of girls and boys. The findings are taken up in the study to make recommendations for policy and practice, and future research. A key recommendation highlights the need for teachers to have deeper and more sophisticated understandings of gender, an area which is currently neglected in both Scottish educational policy and in teacher education programmes. It also recommends that pupils are given the opportunity to gain a greater understanding of how their gender construction affects their educational experiences. Finally, this research calls for further exploration into how young people shape their gendered identities within the rural setting, an area where there is a dearth of research.This ethnographic case study examines how pupils' gendered identities are constructed in one rural secondary school in Scotland. It utilises the work of Michel Foucault and Judith Butler to provide theoretical insight into how and why pupils take up particular gendered positions in the school. Data collection is primarily by ethnographic observation, supported by semi-structured interviews. The findings highlight the discursive role of peer interactions in affecting how pupils shape their gendered identities, with boys seen to be more affected by peer influences than girls. Subject choices emerged as the strongest gender-related curricular theme; girls in the school appear somewhat bound by gender norms when making subject choices throughout their school career. Insights into how some pupils and teachers perceive the rural space as a masculine one also emerged in the data. Overt femininity was seen as very much at odds with the rural landscape, meaning that some girls find conflict in how they construct their feminine identity. The findings also suggest that teacher discourse can reinforce traditional constructs of masculinities and femininities, and that some teachers' understandings of gender rely on binary views of girls and boys. The findings are taken up in the study to make recommendations for policy and practice, and future research. A key recommendation highlights the need for teachers to have deeper and more sophisticated understandings of gender, an area which is currently neglected in both Scottish educational policy and in teacher education programmes. It also recommends that pupils are given the opportunity to gain a greater understanding of how their gender construction affects their educational experiences. Finally, this research calls for further exploration into how young people shape their gendered identities within the rural setting, an area where there is a dearth of research
Characterising single and combination therapies in the human glioblastoma cell line U87
No full textGlioblastoma Multiform (GBM) is the most common lethal cancer within the central nervous system, accounting for 51% of all gliomas, with a median patient survival between 12 and 14 months post diagnosis. Current treatments employed on patients include surgery, radiotherapy and temozolomide, however with the chemotherapeutic and radiation regimes, an accumulation of resistance to treatments often develops in patients due to the cancers heterogeneous nature. Repurposing of drugs is a novel approach to targeting GBM, with several studies and clinical trials reporting promising effects of use of the anti-alcoholism drug disulfiram in combination with temozolomide, and also the use of multiple sclerosis treatment dimethyl fumarate incombination with temozolomide. The aims of this study were to investigate the cytotoxic effect of fixed regressive ratio combinations of treatments on the human GBM cell line U87 cells for assessing combination synergism through combination index analysis. The study also aimed to characterise the U87 cellline response to the combination models through an array of mechanistic assay cascades. Fixed regressive ratio models of combinations were formulated utilising IC50 values from single agent clonogenic assays as the highest combination concentration ratio. Characterisation of the U87 cells under combination treatment was assessed through changes in cell cycle distribution, dynamics of DNA double stranded break formation and repair by γ-H2AX assays and apoptotic cell population changes by Annexin V assays. This study has characterised combinations of DMF and DSF, TMZ and DSF, and TMZ and DMF on the U87 cell line. Significant cytotoxicity was observed with each single agent and each combination against the control. Mechanistic assays for each combination did not show any significant enhancement of cell cycle arrest or apoptosis instigation, but observed significant changes in response to DNA damage under combinations of TMZ and DSF, and TMZ and DMF against the control. Combination TMZ and DSF also showed the most synergism of the 3 combinations examined, with the higher 3 concentrations in the model observing a synergistic effect on the U87 cells by combination index analysis. Whereas this synergistic relationship was seen at the lowest concentration of DMF and DSF and only at the highest concentrations for TMZ and DMF, therefore showing TMZ and DSF to have the greatest potential for further analysis into combination treatments for glioblastoma.Glioblastoma Multiform (GBM) is the most common lethal cancer within the central nervous system, accounting for 51% of all gliomas, with a median patient survival between 12 and 14 months post diagnosis. Current treatments employed on patients include surgery, radiotherapy and temozolomide, however with the chemotherapeutic and radiation regimes, an accumulation of resistance to treatments often develops in patients due to the cancers heterogeneous nature. Repurposing of drugs is a novel approach to targeting GBM, with several studies and clinical trials reporting promising effects of use of the anti-alcoholism drug disulfiram in combination with temozolomide, and also the use of multiple sclerosis treatment dimethyl fumarate incombination with temozolomide. The aims of this study were to investigate the cytotoxic effect of fixed regressive ratio combinations of treatments on the human GBM cell line U87 cells for assessing combination synergism through combination index analysis. The study also aimed to characterise the U87 cellline response to the combination models through an array of mechanistic assay cascades. Fixed regressive ratio models of combinations were formulated utilising IC50 values from single agent clonogenic assays as the highest combination concentration ratio. Characterisation of the U87 cells under combination treatment was assessed through changes in cell cycle distribution, dynamics of DNA double stranded break formation and repair by γ-H2AX assays and apoptotic cell population changes by Annexin V assays. This study has characterised combinations of DMF and DSF, TMZ and DSF, and TMZ and DMF on the U87 cell line. Significant cytotoxicity was observed with each single agent and each combination against the control. Mechanistic assays for each combination did not show any significant enhancement of cell cycle arrest or apoptosis instigation, but observed significant changes in response to DNA damage under combinations of TMZ and DSF, and TMZ and DMF against the control. Combination TMZ and DSF also showed the most synergism of the 3 combinations examined, with the higher 3 concentrations in the model observing a synergistic effect on the U87 cells by combination index analysis. Whereas this synergistic relationship was seen at the lowest concentration of DMF and DSF and only at the highest concentrations for TMZ and DMF, therefore showing TMZ and DSF to have the greatest potential for further analysis into combination treatments for glioblastoma
The infuence of hail on wind turbine blade leading edge erosion and damage
No full textWind turbine blade damage, particularly leading edge erosion, is a signifcant problem faced by the renewable energy industry. Wind turbines are subject to a wide range of environmental factors during a 20+ year lifespan, with hailstones often touted as a key contributor to the deterioration of blade profile. The consequences of blade damage are exhibited in terms of cost of component repair but, perhaps more seriously, in the reduced performance and thus annual energy production (AEP) of the turbine.;This thesis firstly presents the likelihood of hail events with respect to wind turbine locations, from an investigation of UK meteorological data. Three datasets were obtained: surface observations from UK-wide MIDAS stations, detailing back to 1949; as well as precipitation individual measurements from instruments located at CFARR and NERC facilities, also located in the UK. The prevalence of hail incidents is related to both onshore and offshore wind turbine operation.;Particular attention was paid to the rotational speed of the wind turbine blades, which was determined to be a fundamental component of the energy associated with hail impact.;From these impressions, an experimental campaign was carried out to investigate the effects on of repeated impact of simulated hail ice (SHI) on composite materials. Hailstones at four different diameters (5 mm, 10 mm, 15mm and 20mm) were fired at a range of velocities and for different numbers of impacts. Samples used for experimentation were manufactured from triaxial stitched glass fibre (0º, -45º, +45º) and epoxy resin. Damage was analysed qualitatively using scanning electron microscopy.;A computational model was developed to compare the simulated damage of a singular hailstone impact to that of the experimental findings and examine other parameters not available in a practical setting. A survey of calculation methods was undertaken, to determine the elastic properties of the composite required prior to simulation. Threshold velocities were obtained for the onset of damage caused by singular impact of the different diameters of SHI.Wind turbine blade damage, particularly leading edge erosion, is a signifcant problem faced by the renewable energy industry. Wind turbines are subject to a wide range of environmental factors during a 20+ year lifespan, with hailstones often touted as a key contributor to the deterioration of blade profile. The consequences of blade damage are exhibited in terms of cost of component repair but, perhaps more seriously, in the reduced performance and thus annual energy production (AEP) of the turbine.;This thesis firstly presents the likelihood of hail events with respect to wind turbine locations, from an investigation of UK meteorological data. Three datasets were obtained: surface observations from UK-wide MIDAS stations, detailing back to 1949; as well as precipitation individual measurements from instruments located at CFARR and NERC facilities, also located in the UK. The prevalence of hail incidents is related to both onshore and offshore wind turbine operation.;Particular attention was paid to the rotational speed of the wind turbine blades, which was determined to be a fundamental component of the energy associated with hail impact.;From these impressions, an experimental campaign was carried out to investigate the effects on of repeated impact of simulated hail ice (SHI) on composite materials. Hailstones at four different diameters (5 mm, 10 mm, 15mm and 20mm) were fired at a range of velocities and for different numbers of impacts. Samples used for experimentation were manufactured from triaxial stitched glass fibre (0º, -45º, +45º) and epoxy resin. Damage was analysed qualitatively using scanning electron microscopy.;A computational model was developed to compare the simulated damage of a singular hailstone impact to that of the experimental findings and examine other parameters not available in a practical setting. A survey of calculation methods was undertaken, to determine the elastic properties of the composite required prior to simulation. Threshold velocities were obtained for the onset of damage caused by singular impact of the different diameters of SHI
An analysis of processes and contexts for ICT interventions in Malawian primary school education system
Get PDFThe introduction of Information and Communication Technology (ICT) in education has greatly transformed and improved the quality of teaching and learning all over the world. In Malawi, efforts are continuously being directed towards having ICT resources in all primary schools through different ICT interventions. However,though the interventions are likely to be widespread, there is no empirical evidence if the interventions are fully adopted and purposively used by the schools and teachers respectively. While there is considerable evidence to show that the integration of ICT intervention in classrooms is influenced by the entire education system, research on ICT in education is generally limited to the study of teacher level factors.This research examines how ICT interventions in Malawi primary school education system are planned, introduced and guided, and how these processes configure and influence adoption and use of the interventions by schools and teachers,respectively. Based on research questions about how the ICT interventions are conceptualized, implemented and integrated, the main aim of this study is to analyse the activities and processes taking place in the contexts that the ICT interventions are implemented by linking teachers' ICT practices in classrooms to particular mediating processes and contexts.;The study used a qualitative research approach. It firstly investigated the roles,processes and collaborations between government institutions and ICT providers in the conceptualisation of the ICT interventions through interviews and analysis of documents. The baseline data generated from this phase was used to identify case study schools that were used to investigate how the interventions are adopted and used, through interviews with school heads and teachers, classroom observations and analysis of documents. An Activity System Analysis was used to draw relationships between and within how the interventions are conceptualised at national level, how they are implemented in the schools and integrated in the classrooms.The findings reveal gaps in the national education plans and policies as formal guidelines that regulate investments in the primary school education system. The efforts by the various ICT interventions providers are unguided and unregulated,and the process of conceptualising and implementing the ICT interventions in primary education is still in a form of experimentation, being led by the interventions providers rather than the Ministry of Education. This presents tensions as the schools and the teachers try to accommodate requirements for implementing and integrating different ICT interventions without any policy frameworks, curriculum guidelines, ICT training and technical support.The implications from this study reveal the need for policy makers, planners and education practitioners to generate rationale, goals, and vision on how the Malawi primary school education system can incorporate the ICT interventions; guide specific roles for relevant stakeholders in the design and development of specific ICT interventions; produce specific plans and curricula for teacher training and development; and guide the development of school-based ICT plans that can facilitate successful adoption and integration of the ICT interventions.The introduction of Information and Communication Technology (ICT) in education has greatly transformed and improved the quality of teaching and learning all over the world. In Malawi, efforts are continuously being directed towards having ICT resources in all primary schools through different ICT interventions. However,though the interventions are likely to be widespread, there is no empirical evidence if the interventions are fully adopted and purposively used by the schools and teachers respectively. While there is considerable evidence to show that the integration of ICT intervention in classrooms is influenced by the entire education system, research on ICT in education is generally limited to the study of teacher level factors.This research examines how ICT interventions in Malawi primary school education system are planned, introduced and guided, and how these processes configure and influence adoption and use of the interventions by schools and teachers,respectively. Based on research questions about how the ICT interventions are conceptualized, implemented and integrated, the main aim of this study is to analyse the activities and processes taking place in the contexts that the ICT interventions are implemented by linking teachers' ICT practices in classrooms to particular mediating processes and contexts.;The study used a qualitative research approach. It firstly investigated the roles,processes and collaborations between government institutions and ICT providers in the conceptualisation of the ICT interventions through interviews and analysis of documents. The baseline data generated from this phase was used to identify case study schools that were used to investigate how the interventions are adopted and used, through interviews with school heads and teachers, classroom observations and analysis of documents. An Activity System Analysis was used to draw relationships between and within how the interventions are conceptualised at national level, how they are implemented in the schools and integrated in the classrooms.The findings reveal gaps in the national education plans and policies as formal guidelines that regulate investments in the primary school education system. The efforts by the various ICT interventions providers are unguided and unregulated,and the process of conceptualising and implementing the ICT interventions in primary education is still in a form of experimentation, being led by the interventions providers rather than the Ministry of Education. This presents tensions as the schools and the teachers try to accommodate requirements for implementing and integrating different ICT interventions without any policy frameworks, curriculum guidelines, ICT training and technical support.The implications from this study reveal the need for policy makers, planners and education practitioners to generate rationale, goals, and vision on how the Malawi primary school education system can incorporate the ICT interventions; guide specific roles for relevant stakeholders in the design and development of specific ICT interventions; produce specific plans and curricula for teacher training and development; and guide the development of school-based ICT plans that can facilitate successful adoption and integration of the ICT interventions
Photoluminescence study of Cu(In,Ga)Se2 and Cu2ZnSnSe4 used for thin film solar cells
Get PDFIn this study we were trying to answer the question why the best laboratory size CuIn1-xGaxSe2-based (CIGSe) solar cells have been achieved at about 30% Ga, whereas the optimal band gap requires much higher Ga content (around 50%). Also for the first time ever we examined the effects of 4 keV Ar+ irradiation on optical properties of Cu2ZnSnSe4 (CZTSe) thin films. Photoluminescence (PL) measurements were performed on samples of CIGSe single crystals with x=0, 0.05, 0.10, 0.25, 0.50, 0.75, 1 and on samples of CZTSe thin films before and after Ar+ irradiation.;The impact of variations in excitation intensity and temperature on the nature of the PL bands was investigated. For most CIGSe samples band-tail (BT) recombination coupled with band-band (BB) transition were identified as being responsible for the obtained PL peaks. The calculated band tails are deeper in CuGaSe2 than in CuInSe2, explaining why an increase in Ga content x > 0.3 does not improve the efficiency of solar cell.;Also band-impurity (BI) transition and donor acceptor pair (DAP) recombination were discovered. For the first time ever excitons in the CIGSe samples with 5% and 10% Ga content were clearly observed and identified. In the CZTSe samples BI recombination was established as the main source of PL. Ar+ irradiation of CZTSe produced significant changes in the material: reduced PL intensity and creation of tail defect complexes supported by an increase in the average band tail depth γ from 25 to 30 meV as well as increase in the activation energy from 75 to 88 meV.;The composition of the CIGSe and CZTSe samples was investigated using energy dispersive x-ray (EDX) analysis and wavelength dispersive x-ray (WDX) technique, respectively. According to the microscopy results, calculated cation ratios proved the nature of established recombinations.In this study we were trying to answer the question why the best laboratory size CuIn1-xGaxSe2-based (CIGSe) solar cells have been achieved at about 30% Ga, whereas the optimal band gap requires much higher Ga content (around 50%). Also for the first time ever we examined the effects of 4 keV Ar+ irradiation on optical properties of Cu2ZnSnSe4 (CZTSe) thin films. Photoluminescence (PL) measurements were performed on samples of CIGSe single crystals with x=0, 0.05, 0.10, 0.25, 0.50, 0.75, 1 and on samples of CZTSe thin films before and after Ar+ irradiation.;The impact of variations in excitation intensity and temperature on the nature of the PL bands was investigated. For most CIGSe samples band-tail (BT) recombination coupled with band-band (BB) transition were identified as being responsible for the obtained PL peaks. The calculated band tails are deeper in CuGaSe2 than in CuInSe2, explaining why an increase in Ga content x > 0.3 does not improve the efficiency of solar cell.;Also band-impurity (BI) transition and donor acceptor pair (DAP) recombination were discovered. For the first time ever excitons in the CIGSe samples with 5% and 10% Ga content were clearly observed and identified. In the CZTSe samples BI recombination was established as the main source of PL. Ar+ irradiation of CZTSe produced significant changes in the material: reduced PL intensity and creation of tail defect complexes supported by an increase in the average band tail depth γ from 25 to 30 meV as well as increase in the activation energy from 75 to 88 meV.;The composition of the CIGSe and CZTSe samples was investigated using energy dispersive x-ray (EDX) analysis and wavelength dispersive x-ray (WDX) technique, respectively. According to the microscopy results, calculated cation ratios proved the nature of established recombinations
Shock estimation in supersonic vehicles
Get PDFImproving the design of future high-Mach vehicles is crucial to enhance performance,safety and sustainability of future air travel. Advanced designs can be realized by improving low fidelity modelling in the context of Multidisciplinary Design Optimization (MDO) on one side and making the use of high fidelity tools more efficient in the context of Multi-fidelity Design Approaches (MFDA) on the other.This thesis presents the formulation of an advanced low order model for the estimation of the shock structure generated by vehicles flying in the supersonic and hypersonic regimes. Taking as inputs the geometry and the flow conditions, the proposed approach addresses, in one cohesive methodology, attached and detached shocks in two and three dimensions as well as shock structures composed of multiple shocks. The procedure is based on classical supersonic flow theories and has been verified against computational fluid dynamics simulations.The proposed methodology allows for a cost-effective estimation of shock wave patterns and their impingement on the vehicle surface on one side, while on the other it can be used to realize a-priori shock-fitted meshes reducing someof the uncertainty while generating them for high-fidelity CFD simulations.Improving the design of future high-Mach vehicles is crucial to enhance performance,safety and sustainability of future air travel. Advanced designs can be realized by improving low fidelity modelling in the context of Multidisciplinary Design Optimization (MDO) on one side and making the use of high fidelity tools more efficient in the context of Multi-fidelity Design Approaches (MFDA) on the other.This thesis presents the formulation of an advanced low order model for the estimation of the shock structure generated by vehicles flying in the supersonic and hypersonic regimes. Taking as inputs the geometry and the flow conditions, the proposed approach addresses, in one cohesive methodology, attached and detached shocks in two and three dimensions as well as shock structures composed of multiple shocks. The procedure is based on classical supersonic flow theories and has been verified against computational fluid dynamics simulations.The proposed methodology allows for a cost-effective estimation of shock wave patterns and their impingement on the vehicle surface on one side, while on the other it can be used to realize a-priori shock-fitted meshes reducing someof the uncertainty while generating them for high-fidelity CFD simulations
Control of human inflammatory cell responses by prostaglandins and related metabolites
No full textInflammation is an essential component of the innate immune system and is crucial for protecting against bacterial infection. The stimulation of human inflammatory cells by bacterial LPS triggers the production of pro-inflammatory cytokines, especially TNF-α, which perpetuate this response. Monocytes produce these primary mediators of inflammation in abundance and are thus highly important inflammatory cells. The production of cytokines such as TNF-α leads to the biosynthesis of secondary mediators of inflammation, specifically prostaglandins, which are lipid-derived mediators that initiate the physiological changes responsible for the symptoms of inflammation. Prostaglandins also play an immunomodulatory role within the inflammatory response by suppressing the production of pro-inflammatory cytokines particularly TNF-α. This suppression occurs in a negative feedback regulatory manner in the late stages of infection suggesting a role for prostaglandins in the resolution of inflammation. Such resolution is vital as chronic inflammation can cause significant damage to healthy tissues. The project therefore studied the immunomodulatory effect of the prostaglandin D2 metabolite, 15d-PGJ2, on human monocytic cell activities specifically the production of TNF-α in response to bacterial LPS. This involved the growth and culture of the human monocytic cell line, THP-1, and use of a human TNF-α ELISA system. Mechanistic studies investigated the specific receptor and signalling pathways mediating this effect by utilising pharmacological agents that interfere with these systems. The study surmised that 15d-PGJ2 was able to downregulate the production of TNF-α in human monocytes following LPS stimulation and that this suppression appears to occur via Gi-signalling involving the DP2 prostanoid receptor. Further targeted investigations into the pathways that mediate the suppressive actions of 15d-PGJ2 may therefore reveal a novel therapeutic intervention for inflammatory conditions.Inflammation is an essential component of the innate immune system and is crucial for protecting against bacterial infection. The stimulation of human inflammatory cells by bacterial LPS triggers the production of pro-inflammatory cytokines, especially TNF-α, which perpetuate this response. Monocytes produce these primary mediators of inflammation in abundance and are thus highly important inflammatory cells. The production of cytokines such as TNF-α leads to the biosynthesis of secondary mediators of inflammation, specifically prostaglandins, which are lipid-derived mediators that initiate the physiological changes responsible for the symptoms of inflammation. Prostaglandins also play an immunomodulatory role within the inflammatory response by suppressing the production of pro-inflammatory cytokines particularly TNF-α. This suppression occurs in a negative feedback regulatory manner in the late stages of infection suggesting a role for prostaglandins in the resolution of inflammation. Such resolution is vital as chronic inflammation can cause significant damage to healthy tissues. The project therefore studied the immunomodulatory effect of the prostaglandin D2 metabolite, 15d-PGJ2, on human monocytic cell activities specifically the production of TNF-α in response to bacterial LPS. This involved the growth and culture of the human monocytic cell line, THP-1, and use of a human TNF-α ELISA system. Mechanistic studies investigated the specific receptor and signalling pathways mediating this effect by utilising pharmacological agents that interfere with these systems. The study surmised that 15d-PGJ2 was able to downregulate the production of TNF-α in human monocytes following LPS stimulation and that this suppression appears to occur via Gi-signalling involving the DP2 prostanoid receptor. Further targeted investigations into the pathways that mediate the suppressive actions of 15d-PGJ2 may therefore reveal a novel therapeutic intervention for inflammatory conditions
Solidification and storage of carbon captured on ships (CCS)
Get PDFIn order to meet the IMO's (International Maritime Organisation) target of 14% reduction of CO₂ emissions from marine activities by 2020, the application of Carbon Capture and Storage (CCS) on ships is considered as an effective way to mitigate the CO₂ emission while other low carbon shipping emission technologies are being developed. A comprehensive literature review of onshore CCS applications has indicated that current CCS technologies could not be implemented on-board directly due to the various limitations of ships, such as constraint space and system retrofit. In this thesis, a novel method of chemical CO₂ absorption and solidification for marine applications is analysed and presented. Technical feasibility and cost assessment of this method are carried out by comparison with the conventional method (liquefaction) for a case study ship. The thesis will also present results obtained from laboratory-scale experiments. Theoretical study and lab-scale experiments have shown that the proposed CO₂ absorption and solidification method is a promising, cost-effective and practicable method for CO₂ emissions reduction on ships. Carbon capture and storage is an excellent solution for reducing the greenhouse gas emissions from applications on shore. A novel method to absorb and solidify CO₂ from the exhaust gases on the ship is proposed and verified. CO₂ gas flow rate, the geometry of the absorption tanks and the concentration of the absorption solution are key factors that affect the reaction efficiency. The experimental results illustrate the impacts of these factors on CO₂ absorption efficiency. Meanwhile, the effects of these key factors on CO₂ absorption rates will also be presented in the CFD simulations of this thesis. Pressure distributions, the concentration of the solution and the velocity of both the gas and the solution during the different processes will be derived from the numerical simulations. The results of the simulations provide fundamental details for the design of a prototype demonstration system on-board a ship. In addition to the key factors discussed above, the effect of atmospheric temperature will be observed and analysed. With a comparison of experimental data and CFD simulation results, it will be demonstrated that the CFD simulations of the effects of CO₂ gas flow rate, the geometry of the absorption container and the concentration of the absorption solution on absorption rate have a good agreement with the experimental results. Optimised values of these factors are obtained from the comparisons and analyses. The numerical simulations will [sic] carried out to test the impact of phase temperature on absorption rate also indicate the optimal temperature for carrying out the absorption process.;As the simulation results match with the experimental results, the simulation model developed is considered to be applicable for a case study ship practical system simulation. Geometry, fluid flow rate, temperature and some other parameters are adjusted to fit a practical system. At this stage, the practical system is designed and the most appropriate absorption process is selected. The designated system is modelled and simulated based on the simulation processes from the lab-scale experiments. The orthogonal design method is applied to optimise the system. Key parameters are varied within a reasonable range so that a large number of trials are initially needed to find the optimal one. With the orthogonal design method, the number of trials is reduced so that computing intensity is reduced and finally the optimised absorption system is derived. The volume required for the precipitation tanks, CaO and CaCO₃ storage tanks and the centrifuge separation are derived and the installation and positioning of these tanks, as well as the positioning of the whole system, will be presented. It is concluded that CCS for marine activities could enable ships to comply with various regional and international CO₂ emissions regulation whilst also maintaining the efficiency of waterborne transportation. The whole design process for the case study ship is presented here and could be applied as a guideline process for new design, analysis and installation.In order to meet the IMO's (International Maritime Organisation) target of 14% reduction of CO₂ emissions from marine activities by 2020, the application of Carbon Capture and Storage (CCS) on ships is considered as an effective way to mitigate the CO₂ emission while other low carbon shipping emission technologies are being developed. A comprehensive literature review of onshore CCS applications has indicated that current CCS technologies could not be implemented on-board directly due to the various limitations of ships, such as constraint space and system retrofit. In this thesis, a novel method of chemical CO₂ absorption and solidification for marine applications is analysed and presented. Technical feasibility and cost assessment of this method are carried out by comparison with the conventional method (liquefaction) for a case study ship. The thesis will also present results obtained from laboratory-scale experiments. Theoretical study and lab-scale experiments have shown that the proposed CO₂ absorption and solidification method is a promising, cost-effective and practicable method for CO₂ emissions reduction on ships. Carbon capture and storage is an excellent solution for reducing the greenhouse gas emissions from applications on shore. A novel method to absorb and solidify CO₂ from the exhaust gases on the ship is proposed and verified. CO₂ gas flow rate, the geometry of the absorption tanks and the concentration of the absorption solution are key factors that affect the reaction efficiency. The experimental results illustrate the impacts of these factors on CO₂ absorption efficiency. Meanwhile, the effects of these key factors on CO₂ absorption rates will also be presented in the CFD simulations of this thesis. Pressure distributions, the concentration of the solution and the velocity of both the gas and the solution during the different processes will be derived from the numerical simulations. The results of the simulations provide fundamental details for the design of a prototype demonstration system on-board a ship. In addition to the key factors discussed above, the effect of atmospheric temperature will be observed and analysed. With a comparison of experimental data and CFD simulation results, it will be demonstrated that the CFD simulations of the effects of CO₂ gas flow rate, the geometry of the absorption container and the concentration of the absorption solution on absorption rate have a good agreement with the experimental results. Optimised values of these factors are obtained from the comparisons and analyses. The numerical simulations will [sic] carried out to test the impact of phase temperature on absorption rate also indicate the optimal temperature for carrying out the absorption process.;As the simulation results match with the experimental results, the simulation model developed is considered to be applicable for a case study ship practical system simulation. Geometry, fluid flow rate, temperature and some other parameters are adjusted to fit a practical system. At this stage, the practical system is designed and the most appropriate absorption process is selected. The designated system is modelled and simulated based on the simulation processes from the lab-scale experiments. The orthogonal design method is applied to optimise the system. Key parameters are varied within a reasonable range so that a large number of trials are initially needed to find the optimal one. With the orthogonal design method, the number of trials is reduced so that computing intensity is reduced and finally the optimised absorption system is derived. The volume required for the precipitation tanks, CaO and CaCO₃ storage tanks and the centrifuge separation are derived and the installation and positioning of these tanks, as well as the positioning of the whole system, will be presented. It is concluded that CCS for marine activities could enable ships to comply with various regional and international CO₂ emissions regulation whilst also maintaining the efficiency of waterborne transportation. The whole design process for the case study ship is presented here and could be applied as a guideline process for new design, analysis and installation
Optical properties and biological applications of ssDNA functionalized gold nanoparticles
No full textDue to the unique optical, thermal and chemical properties, especially with the help of surface modification technology, gold nanoparticles (AuNP) have attracted much attention in the biology application. Among these applications, AuNP molecular beacon (MB), AuNPs functionalized by hair-pin shaped oligonucleotides, is considered as a promising probe for RNA detections in cells through its higher signalto-noise ratio, biocompatibility and high selectivity. In this thesis, the AuNP MB is studied in two phases: in solution and in vitro. In the solution part, time-resolved fluorescence spectroscopy was applied to study the performance of AuNP MB at various complementary DNA concentrations and to reveal the fluorescence quenching efficiency of the AuNP. In the in vitro study, flow cytometry was employed to compare the fluorescence intensity of AuNP MB in normal cells and tumour cells. This work demonstrated the possibility of differentiating tumour cells from benign cells using this technique.Due to the unique optical, thermal and chemical properties, especially with the help of surface modification technology, gold nanoparticles (AuNP) have attracted much attention in the biology application. Among these applications, AuNP molecular beacon (MB), AuNPs functionalized by hair-pin shaped oligonucleotides, is considered as a promising probe for RNA detections in cells through its higher signalto-noise ratio, biocompatibility and high selectivity. In this thesis, the AuNP MB is studied in two phases: in solution and in vitro. In the solution part, time-resolved fluorescence spectroscopy was applied to study the performance of AuNP MB at various complementary DNA concentrations and to reveal the fluorescence quenching efficiency of the AuNP. In the in vitro study, flow cytometry was employed to compare the fluorescence intensity of AuNP MB in normal cells and tumour cells. This work demonstrated the possibility of differentiating tumour cells from benign cells using this technique
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