To see the other types of publications on this topic, follow the link: B620.
Dissertations / Theses on the topic 'B620'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'B620.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Nicol, Anthony. "Speech-enabled application development for young children." Thesis, University of Central Lancashire, 2005. http://clok.uclan.ac.uk/19077/.
Full textAbstract:
There are several activities in the educational development of young children which require them to speak aloud to a parent or teacher. High pupil-teacher ratios and modem lifestyles limit the time available for one-to-one interaction so the benefits of enabling a computer to assist in this area are significant. There are several large international research projects attempting to implement customised systems with the aim of becoming automated reading tutors within the next few years. This thesis considers a different approach; it tests the feasibility of using commercial speech recognition technology with young children. Commercial technology has the advantage of being available now and it has matured enough for standards to have been developed which enable a speech application to easily use alternative recognition technologies if required. Recognition accuracy needs to be measurable; to simplify and disambiguate the measurement of recognition accuracy, a new metric has been developed. Improvements in recognition accuracy have been found through experimentation. The experiments need a large amount of speech data from children. To facilitate this, a set of tools has been developed to collect a speech corpus from three different regions of the country then automatically measure the recognition effectiveness under different test conditions. Speech recognition is one of several input modes which support a multimodal interface; for it to be effective, the interface with which it is integrated also needs to be effective, so this thesis additionally studies the area of Child-Computer Interaction; one of the outcomes of this study is a set of interface design guidelines which have been developed through the implementation and evaluation of several multimedia applications. Several user evaluation methods have been used to test the applications with young children in the classroom and their effectiveness is discussed. The thesis integrates the speech recognition and Child-Computer Interaction studies to produce a speech-enabled application using the developed interface design guidelines and proposed speech interface design guidelines. The application was evaluated in the classroom with very encouraging results. The thesis concludes that commercial speech recognition can be used effectively with young children if the limitations, optimisations and guidelines developed during this project are considered.
2
Sjöberg, Robin, and Danny Sibo. "Minimering av kursavvikelse för bottensugen Weda B600." Thesis, KTH, Hållbar produktionsutveckling (ML), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-300123.
Full textAbstract:
Detta examensarbete har genomförts hos Weda AB gällande deras bottensug B600. Syftet med projektet har varit att åstadkomma en ökning av robotens automationsgrad för att eliminera behovet av övervakning och samtidigt minska robotens operationstid per rengöringscykel. För att öka automationsgraden har en kursavvikelse, som uppkommer i samband med robotens övergång från poolens djupa del till dess grunda del, undersökts. Fokus har legat på att minska denna avvikelse genom att ta fram ett mekaniskt tillbehör som enkelt kan monteras på roboten. Två stycken iterationer av prototypen har tillverkats och testats. Den andra iterationen kunde inte validera lösningen på grund av oförutsedda problem. En tredje iteration har som resultat av detta teoretiskt föreslagits med syfte att lösa dessa problem för att kunna validera konceptets verkan. Fortsatt testning av den tredje iterationen kommer därmed att vara avgörande för ifall konceptet som helhet fungerar som tänkt.<br>This thesis has been carried out at Weda AB regarding their bottom suction robot B600. The purpose of the project has been to achieve an increase in the robot's degree of automation to eliminate the need for monitoring and at the same time reduce the robot's operating time per cleaning cycle. To increase the degree of automation, a deviation of the course that occurs in connection with the robot's transition from the deep part of the pool to its shallow part has been investigated. The focus has been on reducing this deviation by developing a mechanical accessory that can be easily mounted on the robot. Two iterations of the prototype have been manufactured and tested. The second iteration could not validate the solution due to unforeseen problems. As a result, a third iteration has been theoretically proposed with the aim of solving these problems. Continued testing of the third iteration will thus be decisive for whether the concept as a whole will work as intended.
3
Panebianco, Vincenzo. "A numerical study of turbulence-flame interaction in mild combustion." Thesis, University of Portsmouth, 2016. https://researchportal.port.ac.uk/portal/en/theses/a-numerical-study-of-turbulenceflame-interaction-in-mild-combustion(0d9aaac8-b620-498a-b6e4-26ff5f45d4d0).html.
Full textAbstract:
The transition in the energy market, from large fossil fuel consumption to the broad diffusion of renewable energies, involves an intermediate phase where more efficient techniques are developed for the existing power generation technologies. Among new combustion techniques, MILD (Moderate or Intense Low-oxygen Dilution) combustion is particularly attractive because of its potential characteristic to enhance thermal efficiency and reduce emissions like nitrogen oxides (NOx). The successful application of MILD combustion requires a significant entrainment of hot combustion products into the fuel and/or oxidizer stream(s), yielding an increase of the reacting mixture temperature over its auto-ignition value. Such intense dilution causes a reduction in peak temperature levels, with a consequent reduction of NOx emissions, and a homogeneous temperature field followed by enhanced flame stability. Also the overall thermal efficiency is improved because of the recuperated heat. The relative ease of obtaining reactant dilution in a full scale burner makes the MILD combustion regime interesting also from a technological point of view. Despite some interesting applications of MILD technique in industrial cases, its broad adoption is prevented by gaps in the knowledge of this combustion regime. Particularly, the development of simple and reliable numerical models is required to allow testing of full scale industrial burners with reasonable computational expense. The present dissertation is focused on how the oxidiser temperature, oxidiser concentration and fuel concentration affect the complex interaction among molecular transport, chemical kinetics and turbulence that leads to self-ignition in MILD combustion. The diffusion-chemistry contribution to ignition is investigated by means of a one dimensional (1D) zero velocity Direct Numerical Simulations (DNS) of two mixing layers representing a cold fuel mixture and a hot diluted oxidiser. Different oxidiser mixtures as well as different fuel blends are considered. Each case studied showed a different ignition behaviour. An in deep investigation of physical and chemical changes observed for each case along the ignition period is provided. A temporal and a spatial scaling methods are proposed to account for ignition behaviour differences and compare cases. The comparison revealed different aspects of the self-ignition process. The differential diffusion effect plays an important role in the early stages of ignition, for cases presenting methane/hydrogen fuel mixture. If high is the level of hydrogen in the fuel blend, major stages of methane (CH<sub>4</sub>) consumption pathway,from the CH<sub>4</sub> dehydrogenation to the carbon dioxide (CO<sub>2</sub>) release, are significantly affected by hydrogen (H<sub>2</sub>) chemistry. In the latest stages of ignition, the methane pathway is also affected by the drop in oxygen level. The influence of turbulence on the diffusion-chemistry interaction is studied by means of three-dimensional (3D) Direct Numerical Simulations modelling a methane/hydrogen circular jet mixing with a diluted oxidiser co-flow. The effects of different fuel and oxidiser blends is also considered in the 3D study. In cases where large is the H2 presence in the fuel jet, the presence of turbulent mixing has a minimal effects on early stages of self-ignition, where instead differential diffusion still plays a major role. As turbulence develops, more marked difference between 1D and 3D studies are observed. The role of turbulent mixing dominates over chemistry where the fuel blend includes a low amount hydrogen. For this configuration the temperature increment is strongly limited compared to corresponding 1D study. The outcome of this study is expected to be of use to other researches in MILD combustion, particularly those adopting existing RANS and LES models to MILD combustion cases.
4
Baldock, Graham. "The application of Western norms in relation to corruption." Thesis, University of Portsmouth, 2018. https://researchportal.port.ac.uk/portal/en/theses/the-application-of-western-norms-in-relation-to-corruption(6906347a-b620-4211-ae4a-adc977f26e02).html.
Full textAbstract:
There is a wealth of literature on the definition of corruption, its effects and preventative measures. Academics, non-government organisations, law and policy makers have grappled with what constitutes a phenomenon, which, despite being secretive, can still have a huge impact on societies, or that is such a common practice that to progress in life there is no alternative but to take part. However, there has never been a study that has utilised the opinions of the Anti-Bribery & Corruption function within the financial services sector and collectively analysed these against two other forms of data collection. The project has gathered opinions across three Strands. These included the interviewing of 10 Anti-Bribery & Corruption specialists in the UK, the issuance of an anonymous survey which received 173 responses and three focus groups held with financial services professionals in Hong Kong with eight attendees, India with eight attendees and Mexico with 10 attendees. This thesis presents a collective view on the challenges of defining corruption and the differences in legislation, along with an analysis as to which preventative measures are the most effective at reducing corruption. It is clear that even from a small-scale study corruption does not distinguish between western or non-western countries, although the visibility of it in everyday life may differ. Findings are given and recommendations are made to produce a global definition, supported by guidance notes; to increase academic research on corruption within developing countries; and to raise awareness of the limitations of Transparency International's Corruption Perceptions Index and the consequences if misused. Additional recommendations are made that, if combined, may help to reduce the impact of corruption.
5
Skládal, Zdeněk. "Možnosti konverze dvoumotorového pístového letounu Beechcraft B60 Duke na turbovrtulový." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229164.
Full textAbstract:
Master’s thesis deals with the issue of a conversion of a twin-engined piston aircraft Beechcraft B60 Duke into turboprop engines Walter M601 or Pratt & Whitney Canada PT6.The paper focuses on a financial analysis of conducting of the conversion, resources needed for a certification, authorization for the traffic in the Czech Republic and determination of the rate of return on investment.The thesis further deals with elaborating of the flight and prerformance characteristics, operation costs of both of the proposed engines and compares them with current characteristics and operation costs.
6
Hankins, Matthew. "The application of Classical Test Theory (CTT) to the development of Patient-Reported Outcome Measures (PROMs) in health services research." Thesis, University of Brighton, 2009. https://research.brighton.ac.uk/en/studentTheses/d1adf40f-f515-4c42-89d7-713d84a5708c.
Full textAbstract:
Patient-Reported Outcome Measures (PROMs) are increasingly used in health services research and clinical practice for the quantification of patient experiences, including quality of life, mood (e.g. depression), and satisfaction with services. Such PROMs usually take the form of questionnaires. The underlying measurement model is derived from psychometric theory, specifically Classical Test Theory (CTT). This model requires statistical analysis of questionnaire data to establish the quality of data so collected, with emphasis on the reliability (reproducibility) and validity (domain-specific measurement) of the data.
7
Blumton, Arlene K. "Factors affecting loggerhead shrike mortality in Virginia." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43080.
Full textAbstract:
I studied loggerhead shrikes (Lanius ludovicianus) in the Shenandoah Valley in Virginia from April
1987 to April 1988; factors affecting mortality rates wring the breeding season, fall dispersal, and
winter were investigated., The high reproductive,success in this study was similar to that reported
by other researchers in the United States. Reproductive success was different among varying grass
heights and varying amounts of bare soil areas within 100 m of shrike nests; success was highest in
habitats with numerous bare soil areas and medium grass. I radio-harnessed fledglings at a mean
age of 56 days to document dispersal, fall home-range areas, and survival rates. During the
postfledging dispersal period, survival rates were 100% fledglings dispersed at a minimum of 78
days of age, and fall home-ranges typically contained medium grass and numerous bare soil areas.
These habitat characteristics may provide shrikes with increased invertebrate availability. Winter
negatively affected the loggerhead shrike population in Virginia; raptor predation was the primary
cause of subadult and adult mortality, and road kill was secondary. Shrikes moved from grassland
areas to shrub-forest areas during inclement weather and preyed on small birds. Home-range sizes
were larger during the winter than at other times of the year. I documented the occurrence of low
levels of organochlorine and organophosphates in all birds analyzed for pesticide contamination.
Also, I present statistical models to predict age and sex of loggerhead shrikes; wing chord and tail
white on rectrix 5 were the most useful variables in discriminating sexes and wing chord was used
in discriminating ages. More research is needed on the effects of raptors on shrike populations and
on the role of foraging habitat on winter areas.<br>Master of Science
8
Suddick, Kitty Maria. "The acute stroke unit as transitional space : the lived experience of stroke survivors and healthcare practitioners." Thesis, University of Brighton, 2017. https://research.brighton.ac.uk/en/studentTheses/e87311ac-cb78-4fe9-b6ee-d61a2dd39414.
Full textAbstract:
The re-conceptualisation of stroke unit provision towards acute and hyperacute care has been a relatively recent development in the United Kingdom. This hermeneutic phenomenological study aimed to explore how the acute stroke unit (ASU) experience, as the phenomenon of interest, was meaningfully lived from a human lifeworld perspective. Eight participants: four stroke survivors and four healthcare practitioners: took part in semi-structured interviews, and if they agreed, an optional creative element. Interviews were recorded then transcribed. Detailed hermeneutic analysis drawing on interpretative phenomenological analysis (IPA) was undertaken firstly on each person’s account, and then across the collective from each perspective. An additional close textual reading was developed for one stroke survivor and one healthcare practitioner. A particular feature of the analysis was its influence in generating an innovative graphic interpretation of the research findings. The stroke survivors experienced the ASU as a lived space in two differentiated forms. The ASU holding space, through the spatial practices of nurses, and others, including similar others (patients), was understood to provide them with protection and safe haven; holding them intimately but also at a distance, so that they could think, make sense, plan and work towards transition. The transitional space of the ASU was experienced by three of them in more disparate ways, and represented how they transitioned their self (for protection, necessity and for recovery) in response to the stroke, the hospital space and the spatial practices of the ASU. The healthcare practitioners experienced the ASU as a space that they produced and appropriated for themselves and others. This was intertwined with their work as existential project; through their relationships with others, and their contribution to patients’ transitional work, they were understood to experience authenticity and belonging. This project was always in the making, and was undertaken amidst the day-to-day pressures on the unit. As a result, three of the health practitioners looked to make sense, navigate, and survive the vulnerability they experienced in relation to their meaningful work, as part of their ASU experience. Further synthesis of these two horizonal1 perspectives elucidated 3 key areas of new insight and understanding: the spatiality of the lived experience of the acute stroke unit, suffering and thriving as a human being, and the intertwining of multiple selves in time and place. The implications of this new knowledge for clinical practice, education, and research are further discussed in this thesis.
9
Huggett, Michael J. "How women diagnosed with Borderline Personality Disorder negotiate identity in relation to risk." Thesis, University of Brighton, 2016. https://research.brighton.ac.uk/en/studentTheses/b89bdeec-8ef7-43d2-8b74-0a77ef602b52.
Full textAbstract:
This thesis examines how women with a diagnosis of borderline personality disorder (BPD) negotiate their identity in relation to risk, also referred to as their ‘risk identity’. This is defined as, ‘…the view people have of themselves and project to others in their talk and actions in relation to risk and risk taking’. The theoretical perspective which underpins the study is informed by ontological realism, epistemological discursive/linguistic social constructionism, and an ideological critical liberatory position primarily derived from the work of Foucault (1978; 1991a; 1991b; 1998; 2002; 2008a; 2008b; 2009). This perspective informed the decision to adopt email interviews as a method for generating appropriate texts for analysis. Eight women diagnosed with BPD were interviewed over a period of ten months. Adopting a critical emancipatory methodology which incorporated feminist principles of research, Lather’s (1991) adaptation of Van Maanen’s (1988 cited in Lather 1991) ‘four tales’ was employed to view and analyse the texts from four theoretical perspectives; a ‘Realist Tale’, a ‘Critical Tale’, a ‘Deconstructivist Tale’, and a ‘Reflexive Tale’. By ‘layering’ these tales, the findings revealed sets of tensions discernable within the context of interactions with staff, the nature of services, and the wider material and discursive resources at play which inform how risk identities are negotiated. Converging Western discourses of the subject, binary gender discourse, neoliberal discourse, ‘psy’ discourses, and discourses around motherhood were found to be key discursive resources through which risk identity is produced, resisted and projected. In addition these to broad discursive findings, the study also contributes to the existing empirical literature that focuses on the lived experience of those with a BPD diagnosis. A conclusion is drawn that women with a BPD diagnosis not only receive a label which discursively excludes them from being able to be viewed as a ‘good subject of psychiatry’ (and hence leads to them being viewed as dangerous and risky), but that their difficulties and need for relational approaches to manage risk and promote recovery run counter to the way that mental health services are structured in the current neoliberal era.
10
Sexton, Mary. "Patient-centredness : a conceptual framework for musculoskeletal physiotherapy." Thesis, University of Brighton, 2011. https://research.brighton.ac.uk/en/studentTheses/7b5f1fd2-cfdd-47ba-b05f-f5d4d12d96e1.
Full textAbstract:
Introduction The centrality of the patient to health care has been increasingly recognised both politically and professionally. Patient-centred care has become synonymous with high-quality care and a number of studies have reinforced patient's desire for, and the positive impact of the approach. Although the concept emerged over 30 years ago, it is still not clear what it is, upon what theories it is based, or how to measure it. Whilst the concept has been explored within medicine, nursing and other allied health professions, within physiotherapy there has only been minimal discussion. The aim of this research was to explore the meaning of patient-centred care in relation to low back pain, from the perspective of musculoskeletal physiotherapists. Methods Purposive sampling was initially used to select participants. Subsequently theoretical sampling was adopted whereby analysis of the data informed the sample selection. Nine musculoskeletal physiotherapists agreed to participate in the study. They ranged in experience from five to 25 years. Individual semi- structured interviews were adopted as the method of data collection. The interviews were audio taped and then transcribed verbatim. Analysis broadly followed the Grounded Theory approach outlined by Strauss and Corbin (1990). It consisted of a process of open, axial and selective coding. Constant comparative analysis resulted in the identification with a core category and three inter-related sub-categories and the development of a substantive theory of patient-centred care.
11
Bocvarov, Spiro. "Time-optimal reorientation maneuvers of an aircraft." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-135603/.
Full text
12
Salsbury, Gail. "Transparency in mental health nursing : a critical focus." Thesis, University of Brighton, 2010. https://research.brighton.ac.uk/en/studentTheses/80fadf49-42ae-4b18-95d9-9fe156325d54.
Full textAbstract:
This study explored the ways experienced mental health nurses working within a local acute mental health NHS Foundation and Teaching Hospital Trust felt about being unobtrusively observed in their everyday clinical practice. Participants were recruited from eight local units: four Community Mental Health Teams (CMHT), one Crisis Resolution Home Treatment Team (CRHT), one inpatient ward, one in-patient rehabilitation unit and an Assertive Outreach Team (AOT).
13
Malim, Michael H. "Analysis of the functions and products of the yeast retrotransposon Ty." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:d02fc435-ceb2-443a-b650-dd0d216b2c7c.
Full textAbstract:
There are 30-35 copies of the retrotransposon Ty in the haploid genome of most laboratory strains of Saccharomyces cerevisiae. Ty elements are 5.9 kb long, have LTRs of 340 bp and produce a genomic RNA that is 5.7 kb in length, through which it transposes. They contain two ORFs; the TYA gene of the class I element Tyl-15 is 1,319 nucleotides long whilst its TYB gene, which possesses the consensus sequences of retroviral acid proteases, reverse transcriptases and integrases, is 3,984 nucleotides long. TYB overlaps TYA by 38 nucleotides at its 5' end and is expressed as a TYA;TYB fusion protein. In an attempt to asign some in vivo functions to the Ty encoded proteins, the whole transcriptional unit of Tyl-15 was overexpressed in yeast. Electron micrographs of the overexpressing cells revealed an abundance of cytoplasmic, ~60 nm virus-like particles (Ty-VLPs). These contain the 5.7 kb Ty RNA and have an associated reverse transcriptase activity. Their major protein is p2 (48 kD), which is a proteolytic derivative of the primary translation product of TYA, pi (50 kD), a protein that is also assembled into particles. A truncated pi, encoded by a TYA gene shortened by 60 codons at its 3' end, still aggregates into particles. Furthermore, the addition of α2-IFN (20 kD) onto its carboxy terminus, to produce a pl-IFN fusion protein of ~68 kD, does not interfere with its particle forming properties. The hybrid VLPs are easy to purify and elicit an antibody response in rabbits to the Ty and IFN epitopes. A series of fragments spanning Tyl-15 were inserted into the packaging analysis vector, pMA924. The association of the resulting PGK-Ty-IFN hybrid RNAs with Ty-VLPs, in the presence of abundant Ty encoded proteins, was analysed by Northern blotting and used to assess the packaging capabilities of Ty RNA. Unexpectedly, RNA sequences that, direct specific packaging are produced from regions throughout Tyl-15. The signals corresponding to TYA are probably located within two regions of the genomic RNA, 5' to nucleotide 236 and 3' to nucleotide 737; those corresponding to TYB are in at least two, currently undefined, areas. The TYB gene of the class II element Tyl-17 overlaps TYA by 44 nucleotides. The fusion of α2-IFN cDNA fragments into all three reading phases of TYB followed by a Western blot analysis demonstrated that, like the TYB gene of Tyl-15, it too is expressed as a TYA:TYB fusion protein.
14
Schlüeter, Dirk Christopher. "Universal moduli of parabolic sheaves on stable marked curves." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:b0260f8e-6654-4bec-b670-5e925fd403dd.
Full textAbstract:
The topic of this thesis is the moduli theory of (parabolic) sheaves on stable curves. Using geometric invariant theory (GIT), universal moduli spaces of semistable parabolic sheaves on stable marked curves are constructed: `universal' indicates that these are moduli spaces of pairs where the underlying marked curve may vary as well as the parabolic sheaf (as in the Pandharipande moduli space for pairs of stable curves and torsion-free sheaves without augmentations). As an intermediate step in this construction, we construct moduli spaces of semistable parabolic sheaves on flat families of arbitrary projective schemes (of any dimension or singularity type): this is the technical core of this thesis. These moduli spaces are projective, since they are constructed as GIT quotients of projective parameter spaces. The stability condition for parabolic sheaves depends on a choice of polarisation and is derived from the Hilbert-Mumford criterion. It is not quite the same as traditional stability with respect to parabolic Hilbert polynomials, but it is closely related to it, and the resulting moduli spaces are always compactifications of moduli of slope-stable parabolic sheaves. The construction works over algebraically closed fields of arbitrary characteristic.
15
Bartlett, William Jonathan Osborne. "A critical edition of the Athis und Prophilias fragments with introduction, commentary, rhyme- and word-lists." Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:cbaee0d7-ed4d-4554-b62b-76ce77249c16.
Full textAbstract:
The introduction contains separate studies of the manuscripts, their orthographies, the rhymes, metre and treatment of source material. Both the orthographic studies and the rhyme—grammar reveal Athis to be a CG poem with no real evidence of Rhenish provenance. The metrical studies, dealing with vowel collision and units of one and three syllables, show how the <u>Athis</u> poet pursued various legitimate rhythmic options in his attempt to introduce variation to the tedium of regular alternation. The most positive results emerge from the comparison of <u>Athis</u> with its OF source, the <u>Roman d'Athis</u>. The dependence of the German text on the OF poem can be proved through misunderstandings of lines and part—lines of the <u>Rd'A</u> enshrined in proper names in the German text. By far the most important aspect of the German poet's adaptation is his sense of history. Ancient Rome and Athens are presented in an entirely different way in the German text. In particular, the large scale descriptions of ceremonies and major events are scenically developed under the influence of medieval historiographic ideas. Further supplementary source material is provided by a Pseudo—Ovidian treatment of <u>Pyramus and Thisbe</u> and a number of medieval military and judicial customs associated with Roman models. In general <u>Athis</u> is shown to be indebted to a medieval German self—awareness of <u>Romanitas</u>.
16
Picco, Noemi. "Tumour-stromal interactions in cancer progression and drug resistance." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c05135ed-2334-4788-b623-262b5056a014.
Full textAbstract:
The typical response of cancer patients to treatment is only temporary, and is often followed by relapse. The failure of various therapeutic strategies is commonly attributed to the emergence of drug resistance. The response patterns for patients under such treatments indicate that complex dynamics regulate the response of the tumour to the therapy. The environment in which the tumour lives (the stroma) is known to be a modulator of multiple mechanisms that lead to drug resistance and seems to be a likely candidate for explaining some of this complexity. Understanding the role of stromal cells in the promotion of drug resistance is critical for the design of optimal treatment strategies, and for the development of novel therapies that selectively target both the tumour and the stroma. In this thesis we design two novel mathematical models that describe cancer growth within its environment and the evolution of drug resistance within spatially complex and temporally dynamic tumours. A compartment model captures clinically observed dynamics and allows direct comparison with experimental data, facilitating model parametrisation and the understanding of inter-tumour heterogeneity. An individual cell-based model highlights the key role of local interactions, determining heterogeneity at the tissue scale, that will eventually determine treatment outcome. A non-spatial approximation of this second model allows us to find analytic guidelines for the design of effective therapy. These tools allow the simulation of a range of treatment strategies (including combination of different drugs and variation of schedule) as well as the investigation of therapy response based on patient- or organ-specic parameters. The work developed in this dissertation is based on the paradigmatic biology of melanoma and non-small cell lung cancer. Its results are therefore applicable to a variety of cancer treatments that target similar processes, and whose therapeutic failure can be attributed to environment-mediated drug resistance.
17
Zhu, Jiming. "Assessing the viability of general practice in China." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:b33cb439-3f72-44ec-b628-5e0d893bc1f1.
Full textAbstract:
<b>Background:</b> China has had a well-known tradition of primary care, particularly its barefoot doctors in the 1960s and 1970s, and it contributed to the Declaration of Alma-Ata. In 2011 China formally launched a new, ambitious plan of establishing a system of general practitioner (GP) care by 2020; and aims to train 300,000 GPs. My thesis assesses whether this new strategy for general practice is viable. <b>Methods:</b> I used a systematic approach with a rigorous pre-set protocol to review the government documents at national level in relation to GPs. I undertook a policy implementation study, in Henan Province, using a mixed methods approach. The qualitative element was a thematic analysis of focus group discussions (FGDs) and semi-structured interviews. The quantitative element comprised structured questionnaires. Two rounds of fieldwork generated eight FGDs, seven semistructured interviews, and 1,887 quantitative questionnaires covering medical students, grassroots doctors and GP residents (together called the policy implementation targets [PITs]). <b>Main findings:</b> The document analysis shows that the Chinese government has made great efforts in GP capacity building. However, the government definition of GPs, based on an idealistic primary care framework, is too broad to be a practical guide to the training and work of GPs. The PITs have some intuitive awareness of the attributes of general practice (comprehensiveness, first contact, continuity and coordination), but often misinterpret what GPs actually do, or base their understanding on their knowledge of the existing hospital-dominated system. Eight factors (such as low income) are identified as deterrents to medical students opting to be GPs. Understandings of what being a GP entails is more likely than the deterrents to influence the students' decision to become a GP. <b>Conclusions:</b> China is unlikely to have a GP system by 2020. Pursuing the quantity of GPs on its own is meaningless, as the number depends on how to define GPs. Top priority is to establish clarity about the GP role, which requires rigorously regulating China's medical pluralism, reversing the dominance of hospital and specialist practice model, and reforming the wider political and social environment in respect of health care.
18
Trudgill, Marian Linda. "The representation of chivalric ideals in twelfth-century northern France." Thesis, University of Bristol, 2001. http://hdl.handle.net/1983/1fa14d71-b640-4579-954c-0b2de31f51fe.
Full text
19
McCarry, Melanie J. "The connection between masculinity and domestic violence : what young people think." Thesis, University of Bristol, 2004. http://hdl.handle.net/1983/a8ed54c4-b62c-4ed5-bb11-d75423d98c9a.
Full textAbstract:
This thesis examines young people's views about male violence and specifically domestic violence. There are various theoretical analyses of domestic violence, but it is argued that the feminist analysis has the most to contribute to understandings because only the feminist critique centralises gender and locates it within the power and control framework. The radical feminist analysis, which is applied in this thesis, argues that domestic violence is supported ideologically and structurally through patriarchy and thus, all male violence must be recognised as part of the same phenomenon of an abuse of power and control. The radical feminist approach also argues that male gender behaviour, or `masculinity', as currently socially constructed, is central to male violence. Often the research on masculinity legitimates male gender behaviour and the radical feminist perspective argues that there has to be a critical analysis of masculinity in order not to be complicit in perpetuating the hegemony of masculinity and male gender behaviour. It is thus argued that an understanding of normative masculinity is essential to understanding male violence against women. This study's focus on young people made it necessary to critique the literature on young people and the development of gender roles particularly in relation to masculinity. Recent studies have identified that, despite the recent domestic violence campaigns and interventions, young people have an exceptionally high tolerance and expectation of male violence. In order to explore this, focus group interviews were conductedw ith 77 young peoplei n ten different secondarys choolsi n Glasgow. The primary research aim was to investigate whether young people conceptualise violence as integral to normative masculinity. It is hoped that the findings of this researchp roject may build upon the current understandingso f domesticv iolencea nd may be used to optimise the efficacy of future intervention projects with young people.
20
McCall, MacBain Marcy C. "Yoga as a complex intervention and its development for health-related quality of life in adult cancer." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:c7259cbe-b6c0-42f8-b893-79306cdccdfa.
Full textAbstract:
The aim of this thesis was to develop yoga as a complex intervention in health care for the improvement of health-related quality of life (HRQoL) in adult cancer. As the Indian tradition of practising yoga increases in popularity worldwide, populations in the West are beginning to see yoga as an opportunity to prevent and treat health conditions. The Medical Research Council’s framework has provided a methodology to address a paucity of coherent evidence for the myriad of unsupported health claims made by yoga enthusiasts. The thesis structure included a step-by-step approach to investigate biomedical theories of how yoga might work to improve health, to synthesise evidence of yoga interventions, to model their process and outcomes, and to test evaluation procedures in the context of a randomised controlled trial (RCT). The results of a bibliometric analysis indicated an overall increase in the publication rate of yoga research in health care, and in 2005 this research began to focus on cancer. A component analysis, semi-structured patient interviews (n=10) and oncologist surveys (n=29) were successively designed, implemented and analysed to advance a model of yoga intervention specific to adult cancer. The cumulative results were applied to design three yoga interventions randomly allocated to men and women receiving treatment for cancer (n=15). Outcomes of the feasibility study demonstrated that yoga intervention is appropriate for adult patients and can be administered safely in a clinical setting. In its conclusion, this thesis produces evidence-based support for the optimisation of yoga intervention in the context of a large-scale RCT for HRQoL in adult cancer, and it provides recommendations to improve research methodology and reporting of complex interventions in health care.
21
Taylor, Aimee Rebecca. "Estimation of Plasmodium falciparum allele and multi-SNP haplotype and genotype frequencies." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c192e7cb-b6e0-4e23-a880-de46d668ef07.
Full textAbstract:
Malaria kills hundreds of thousands of people each year, yet is entirely curable given prompt treatment. Malaria parasites evolve resistance to antimalarial drugs, hence routine surveillance of antimalarial resistance is vital. The surveillance of parasite genetic markers of resistance provides an economical adjunct to clinical efficacy trials, and has the potential to resolve drug specific resistance ahead of clinical failure. To monitor spatiotemporal changes using genetic markers, frequencies of alleles and/or haplotypes and genotypes spanning multiple single nucleotide polymorphisms (SNPs) are required. However, multiclonal infections complicate frequency estimation, especially in highly endemic regions. With the aim of harnessing the full potential of genetic markers for the surveillance of antimalarial resistance, a statistical model to estimate frequencies is proposed. The model builds upon existing methods (reviewed in chapter 2), without reliance upon experimentally-derived estimates of the sample-wise multiplicities of infection (MOIs). Its ability to generate precise and accurate estimates within a Bayesian framework is documented in chapter 3. In chapter 4, the model is applied to data collected from a cohort of children enrolled in a longitudinal trial in Uganda, generating valuable insight into haplotype frequency trends. In chapter 5, the model is extended to investigate inter-child variability in the aforesaid cohort, revealing a small amount of inter-child variation. In chapter 6, the model is modified to enable the analysis of short-read sequencing data, with application to data from malaria patients in Northern Ghana, providing insight into the extent of within-host diversity and anti-folate resistance in the region. In summary, this thesis documents the development, application, extension and modification of a model designed to estimate population-level frequencies of P. falciparum alleles and multi-SNP haplotypes and genotypes within a Bayesian framework. It is hoped that the model and its proposed framework will provide a practical tool for surveillance of antimalarial resistance, as well as a foundation on which to develop further methods.
22
Matthews, Lucy A. E. "Novel imaging biomarkers for the diagnosis and study of Neuromyelitis optica." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:f00d7dca-8504-4298-b62b-ccbed59fc4fe.
Full textAbstract:
Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing demyelinating neurological condition that requires prompt diagnosis and treatment to prevent the accrual of significant disability, such as blindness and immobility. It is caused by antibodies to the aquaporin-4 water channel, which can be detected within the serum of patients and are therefore a highly specific biomarker for the condition. However NMOSD can have overlapping clinical features with the more prevalent demyelinating disease relapsing remitting multiple sclerosis (RRMS). Thus in the situation of a negative aquaporin-4 antibody assay result diagnostic distinction can be difficult to achieve. This in turn leads to a treatment dilemma as NMOSD requires long term immunosuppression, and disease modifying therapies used in RRMS can worsen disease activity in NMOSD. The work presented in this thesis aimed to find further biomarkers of NMOSD, focusing on conventional and quantitative magnetic resonance imaging, and markers of neurodegeneration. The principle findings are: <ul><li>Lesion probability mapping analysis revealed that T2 lesion distribution and morphology can distinguish RRMS from NMO with a 92% sensitivity and 96% specificity. Radiological criteria to aid diagnosis have been proposed.</li><li>Quantitative imaging methods that provide complementary micro-structural measures within CNS tissue have shown that RRMS is associated with widespread neurodegenerative changes in the normal appearing tissue, where as NMO is lesion focused.</li><li>NMO is not associated with diffuse global neurodegeneration in the non-lesioned CNS tissue over a one-year period as determined by serial MRI.</li><li>Normalised thalamic and whole brain volume can be used in a function to help discriminate NMOSD and RRMS</li></ul> This thesis therefore contributes the knowledge that conventional and quantitative imaging can distinguish NMOSD and RRMS, and provides practical methods in which to apply this to patient management. It is the first longitudinal quantitative imaging study of NMOSD and lends further proof that global or diffuse neurodegeneration of the normal appearing brain or spinal cord tissue is not a feature of this condition.
23
Blackman, James R. "Diet-induced thermogenesis in the domestic chicken." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54737.
Full textAbstract:
Four experiments were conducted to examine the energetic responses of chicks from lines divergently selected for 56-day body weight to caloric intake. Caloric overconsumption or calorie-protein imbalances were induced by providing glucose solutions (16% w/v) in lieu of water in the first experiment, and by force-feeding the diet to crop capacity in the subsequent trials. Feed restriction was accomplished by providing 75% of ad libitum intake each day.
Both low-weight (LN) and high-weight (HN) chicks reduced their voluntary feed intake when glucose solutions were provided; caloric intake was reduced by 25% and 10% in LN and HN chicks, respectively. Weight gain and the deposition of protein and ash in the carcass were reduced by the glucose treatment, but carcass lipid deposition was increased. The efficiency of energy deposition was improved in HN but unchanged in LN chicks. Feed restriction reduced feed intake, energetic efficiency, and gain of body weight, carcass dry matter, protein, lipid and ash. The suppression of lipid deposition was more severe in the LN chicks than in the HNs.
Overfeeding of a complete diet increased body weight, the deposition of all carcass constituents, and energetic efficiency. Feed restriction exerted an opposite effect, with the LN chicks exhibiting more pronounced responses than the HNs. Determined metabolizable energy values of the diet differed among feeding treatments and between lines, and line by feeding treatment interactions were observed.
Body core and surface temperatures demonstrated that the LN chicks were less able than the HNs to maintain homeothermy under treatments imposed. Heat production tended to be increased by overfeeding and reduced by feed restriction. Metabolic rates were higher in LN than in HN chicks when the chicks were fed ad libitum or subjected to restricted feeding, but not when force-fed. The latter observations were attributed to differences in physical activity. Plasma triiodothyronine (T₃) of LN chicks was increased by force-feeding and reduced by restricted feeding, but no significant differences in plasma T₃ occurred in HNs. Thyroxine (T₄) and the T₃:T₄ ratios were unchanged by feed intake, although LNs exhibited higher plasma T₃ and T₃:T₄ ratios than HNs. Although endocrinological changes to caloric consumption analogous to those observed in mammals occurred, energy balance did not confirm the existence of diet-induced thermogenesis in the fowl.<br>Ph. D.
24
Thomas, Ian Richard. "Measurement of properties of the lunar surface using the Diviner Lunar Radiometer experiment on the NASA Lunar Reconnaissance Orbiter." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:33eafce3-fe40-4068-b62e-0bb0f216173a.
Full textAbstract:
The Diviner Lunar Radiometer is a nine-channel radiometer on board the Lunar Reconnaissance Orbiter, launched in June 2009 and currently orbiting the Moon. Diviner is the first orbiting multi-spectral instrument to observe the lunar surface in the mid- and far- infrared, therefore this thesis details the first steps towards utilising observations in this new spectral region. The author, as part of the Diviner instrument team, contributed to the pre-launch testing and calibration of Diviner. Specifically, the transmission profiles of the B2 and B3 filters, which could not be measured after integration into the instrument due to their long wavelength passbands, were determined. Further investigations of the far-infrared mesh filters were also conducted, as the spectral responses of similar mesh filters were found to have broadened after integration into the Mars Climate Sounder instrument, the pre-cursor instrument to Diviner. To test if this would occur in Diviner also, a new setup was made to approximately re-create the instruments' optical layout. No such spectral broadening was measured in the B1, B2 or B3 filters. The linearities of Diviner's detectors were also confirmed through analysis of the pre-flight calibration data. Laboratory emission spectra taken under ambient conditions differ from those taken in a lunar environment, which induces a temperature gradient in soil and mineral samples. Due to a lack of spectra measured under such conditions, which are directly comparable to Diviner‟s measurements, a new chamber for performing high-resolution emission measurements in a simulated lunar environment was built and calibrated. This setup induces a temperature gradient in each sample by heating it from below while it is surrounded by a cooled radiation shield, all enclosed in a very low pressure vacuum chamber. Lunar analogue minerals have been measured, first in reflectance, and then in simulated lunar conditions, forming the basis of a new lunar spectral library. The uses of the mid- and far-infrared have been described herein, utilising calibrated Diviner observations to: [1] map the temperatures of the lunar poles; [2] investigate regions containing higher than average abundances of rocks; and [3] determine the composition of regions of the lunar surface by combining observations with the new spectral library made during this project.
25
Tedeschi, Leonardo Ribeiro. "Lower Cretaceous climate records and the correlation between marine and lacustrine settings (Europe and South America)." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:36b86747-f8f9-4767-b6e0-45301603b15e.
Full textAbstract:
Major changes in watermass chemistry during the opening of the central segment of the South Atlantic, and oceanic anoxic events (OAEs 1a to 1d), represent dramatic events that affected the oceanâatmosphere system during the Early Cretaceous. This thesis addresses the chemostratigraphic correlation of Tethyan and South Atlantic sections based on carbon-, sulphur- and strontium-isotopes (δ<sup>13</sup>C, δ<sup>34</sup>S and <sup>87</sup>Sr/<sup>86</sup>Sr) integrated with other methods to explore the causal links between these phenomena. Firstly, the sedimentation of massive evaporite deposits is discussed and its relationship with the Early Aptian OAE 1a explored. The proposed coincidence in timing between massive evaporite deposition and OAE 1a enhances the understanding of carbon and sulphur cycles in the Early Cretaceous. Secondly, the top of sub-evaporite carbonates in the southern Brazilian basins is identified as having been deposited in a continental environment, and further evidence for its deposition during part of the OAE 1a interval is presented. Thirdly, it is suggested that the formation of the Ontong Java Plateau, already linked to the genesis of OAE 1a, promoted a eustatic sealevel rise responsible for rapid seawater entrance into the southern Brazilian basins during the Early Aptian. Fourthly, the first record of OAE 1a from northeastern Brazil (Sergipe- Alagoas Basin) has been recognized, allowing stratigraphic correlation with southern Brazilian basins. Stratigraphic correlation between the southern Brazilian basins is extended to the Falkland Plateau, where the decrease in the content of organic matter upwards in the stratigraphy of DSDP Site 511 through the BarremianâOAE 1b interval can be related to the evolution of South Atlantic basinal geometry. Finally, in the context of a Tethyan reference section, the record of the Barremian-Aptian boundary and the OAE 1a interval has been characterized in the Tethyan Poggio le Guaine scientific core from MarcheâUmbria, Italy.
26
Polonski, Vyacheslav. "Commitment issues : toward an understanding of young people's social media choices in the multi-platform era." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:6d738215-33d1-4de2-b680-dd3def88f1bd.
Full textAbstract:
Social network sites (SNSs) have become a common part of everyday life for billions of people worldwide. Not everyone uses the same sites, nor are sites functionally equivalent in the eyes of users. Both established platforms and new upstarts may provide novel features or access to new audiences, yet users tend to remain on a few dominant platforms, especially Facebook, the world's reigning social network site. The goal of the present study is to understand why people are committed to specific social network sites, given that no site encompasses either all of a person's social connections or all possible gratifications available from online participation. Further, individuals do not always wish to have a single real-name identity for all online interactions, thus implying the necessary use of multiple accounts or sites. To understand SNS commitment, this study employs a mixed-methods research design by combining findings from a survey of 800 respondents with 50 semi-structured interviews. The research focuses on young adults in the UK and their use of four popular SNSs: Facebook, Twitter, Instagram and Snapchat. Findings indicate that network size has only a marginal effect on commitment, whereas the effect of identity performance is more pronounced, albeit in different ways on different sites. Social and informational gratifications have the strongest effect across all four SNSs, suggesting that commitment is primarily driven by repeated habit-forming experiences. To further help explain SNS commitment, this thesis employs a typology of social media users based on attitudes towards digital technology. It is evident that attitudes explain more variation in commitment than either demographic factors or personality. Qualitative analysis reinforces this finding by showing how users employ specific gratification-based repertoires to determine which sites to use and when. These findings help advance research on affordances, self-presentation and SNS use, while also making practical recommendations for social media platforms.
27
Bentivegna, Valerie. "The biomechanical properties of epithelial cells and tissue in two and three dimensions." Thesis, University of Dundee, 2019. https://discovery.dundee.ac.uk/en/studentTheses/0e957e85-9e8d-46f7-b6f0-9ab3307c43bc.
Full textAbstract:
During development and disease progression, cells and tissue undergo mechanical changes and alter their response to external physical cues. This is also true during the onset of colorectal cancer, the second most common cause of cancer deaths in the Western world. Before the changes that occur during cancer onset can be understood, a better appreciation is needed of the mechanical forces and properties involved. Therefore, there is a drive to develop novel tools to accurately measure biomechanical properties at different spatial scales. 3D cell models are a useful method to understand the mechanical properties at cell and tissue scale, as they provide a more physiologically relevant environment for cells than 2D cell culture. Additional insight may be achieved by complementing experimental approaches with computational models to reveal how the properties of individual cells work as a system to generate the mechanical properties of 3D tissue structures. In this work, Madine-Darby Canine Kidney (MDCK) cells and cysts were used as a model for epithelial tissue. These cells can be genetically modified to mimic the onset of colorectal cancer, by the expression of a truncated Adenomatous polyposis coli (APC) protein: N-APC. N-APC is present in most cases of colorectal cancer and provides a useful tool to study the early changes in colorectal cancer. MDCK cells form spherical cysts up to 100 μm in diameter with a hollow lumen when cultured in an extracellular matrix (ECM) gel. Atomic Force Microscopy (AFM) experiments have revealed that MDCK cells expressing N-APC grown at continued confluency were significantly stiffer than cells expressing only WT-APC. Cells expressing N-APC had an average stiffness of 4.59 ± 1.30 kPa in the nuclear region, while the average stiffness of WT cells was 2.90 ± 0.59 kPa. This is the first time a mechanical effect of N-APC expression has been observed. Adapting AFM for use on 3D tissue models is challenging, as these structures are grown embedded in an ECM gel and cannot be probed directly. This work describes a novel protocol that allowed the AFM cantilever to come in contact with a MDCK cyst surface. These experiments have been used to validate a Finite Ele- ment (FE) model of the mechanical behaviour of an MDCK cyst, that predicted the deformation behaviour of a cyst being compressed by an AFM cantilever. Alternatively, microultrasound (μUS) imaging was evaluated as an approach to provide additional useful information about 3D tissue models, with the benefit that direct contact with the sample is not required. Quantitative analysis of the μUS signal allowed the calculation of the apparent speed of sound through an MDCK cysts, which was on average 1112.96 ± 383.87 m/s. This was significantly lower than the apparent speed of sound through a spheroid (a 3D structure that does not contain a lumen) such as HCT-116 spheroids, which had an average apparent speed of sound of 1494.68 ± 951.82 m/s. This suggests that the speed of sound depends on the geometrical features of a spherical structure. Indeed, FE modelling has confirmed that stronger interference effects occur for a sound wave interacting with a cyst compared to a spheroid due to surface and Lamb waves. In addition, cellular and molecular markers for mechanical stress were identified to determine the effect of static compression applied with a weighted coverslip: compressed cells had nuclei with smoother nuclear envelopes (decrease in amount of folded nuclear envelopes of 32 % ± 41 % for WT-MDCK cells) and an increased vinculin signal (increase of signal intensity of 22 % ± 10 % for WT-MDCK cells) at the junctional membrane. Finally, the use of acoustic radiation force (ARF) was explored as a means of applying compression to cells. While preliminary experiments that exposed the apical surface of samples to continuous acoustic radiation did not reveal an ob- servable effect on the cells, a FE model has been developed to aid further design of ARF experiments. This project explored a range of different tools for studying the mechanical properties of cells and tissue, specifically in the context of 3D models. Experimental approaches have been complemented with FE models to increase understanding of how mechanical properties relate over different length scales, from cells to tissue structures, and how acoustic waves interact with cells and tissue structures. In the future, these approaches could permit further investigation of how the mechanical properties of cells and tissues change during the onset of colorectal cancer.
28
Bloch, Katarzyna. "Structural and bioenergetic changes in tumour spheroids during growth." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:1d7b8669-b62a-4554-bb66-157f54e3ded2.
Full textAbstract:
Multicellular tumour spheroids (TS) are an in vitro model of avascular tumours, and have been widely used to investigate tumour growth, metabolism and hypoxia. The geometry of the TS lends itself to mathematical representation, and theoretical models of TS growth and the development of hypoxia are abundant. With some notable exceptions however, these models have been developed independently of the biological data collection process and are overwhelmingly based upon data from multiple sources. Thus, whilst mathematical modeling has the potential to help explain and guide biological experiments, without reliable data it is unlikely to live up to this expectation. In this thesis, a combination of experimental and theoretical approaches was used to characterize the relationship between proliferation, hypoxia and metabolism during the growth of TS derived from the DLD-1 human colon adenocarcinoma cell line. Experimental data were collected over the entire period of TS growth, generating a high volume of predominantly imaging data. To facilitate the extraction of quantitative information from this, a suite of image analysis software, which is readily applicable to other data sets, was developed. During growth, the DLD-1 TS maintained a macroscopic spherical geometry but at the microscale level the TS boundary was increasingly irregular, with TS disintegrating rapidly after 20 days. Immunofluorescence (IF) studies showed that hypoxia developed soon after TS initiation, followed by the characteristic onset of necrosis. Reduced proliferation was found to be concomitant with the development of hypoxia, although some cells retained proliferative capacity even under severely hypoxic conditions. Towards the end of culture, TS were primarily comprised of severely hypoxic and necrotic cells, a probable cause of disintegration. Mathematical simulation of oxygen gradients in TS using literature-based values for the maximal rate of oxygen consumption was used to estimate the partial oxygen pressure (pO<sub>2</sub>) at which the IF marker of hypoxia was bound. Assuming a spatially-invariant rate of oxygen consumption, the model predicted that the onset of hypoxic binding occurs at pO<sub>2</sub> levels similar to those reported in the literature, however the onset of necrosis was overestimated. Mathematical simulations predicted that oxygen consumption decreases as TSs increase in size, supporting previous observations. The Warburg Effect, where glucose metabolism is favoured even under aerobic conditions, is a hallmark of tumours. Although development of the glycolytic phenotype during TS growth was observed in the form of an elevated activity of the lactate dehydrogenase V (LDHV) enzyme, the activity and expression of other glycolytic enzymes, such as hexokinase II (HKII), was unaltered. Whilst the spatial distribution of HKII was unrestricted throughout the TS's viable fraction, LDHV expression was elevated in regions of hypoxia, suggesting constant adaptation of tumour cells to their microenvironment. In addition to the above findings, the data generated have been collected and analysed in the context of the requirements of theoretical modelling at each step; thus, they can be used to parameterise and inform more sophisticated models of tumour metabolism.
29
Woolerton, Thomas William. "Development of enzymatic H2 production and CO2 reduction systems." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:393741ac-94b1-4d56-b680-d9a434db77e2.
Full textAbstract:
One of today’s most pressing scientific challenges is the conception, development and deployment of renewable energy technologies that will meet the demands of a rapidly increasing population. The motivation is not only dwindling fossil fuel reserves, but also the necessary curtailment of emissions of the greenhouse gas carbon dioxide (a product of burning fossil fuels). The sun provides a vast amount of energy (120,000 TW globally), and one major challenge is the conversion of a fraction of this energy into chemical energy, thereby allowing it to be stored. Dihydrogen (H₂) that is produced from water is an attractive candidate to store solar energy (a ‘solar fuel’), as are high energy carbon-containing molecules (such as CO) that are formed directly from carbon dioxide. One key aspect is the development of catalysts that are able to offer high rates and efficiencies. In biology, some microbes acquire energy from the metabolism of H₂ and CO. The biological catalysts - enzymes - that are responsible are hydrogenases (for the oxidation of H₂ to protons); and carbon monoxide dehydrogenases (CODHs, for the oxidation of CO to CO₂). These redox enzymes, containing nickel and iron as the only metals, are extraordinary in terms of their catalytic characteristics: many are fully reversible catalysts and offer very high turnover frequencies (thousands per second are common), with only tiny energy input requirements. This Thesis uses a hydrogenase from the bacterium Escherichia coli, and two CODHs from the bacterium Carboxydothermus hydrogenoformans, as the catalysts in H2 production and CO₂ reduction systems. Chapter 3 describes the concept and development not of a solar fuel system, but of a device that catalyses the water-gas shift reaction (the reaction between CO and water to form H₂ and CO₂) - a process of major industrial importance for the production of high purity H₂. Chapters 4, 5 and 6 detail photochemical CO₂ reduction systems that are driven by visible light. These systems, operating under mild, aqueous conditions, involve CODHs attached either to TiO₂ nanoparticles that are sensitised to visible light by the co-attachment of a ruthenium-based dye complex, or to cadmium sulfide nanomaterials that, having a narrow band gap, are inherently photoexcitable by visible light. The motivation here is not the construction of technological devices; indeed, the enzymes that are used are fragile, highly sensitive to oxygen, and impossible to scale to industrial levels. Rather, the drivers are those of scientific curiosity (can the incorporation of these remarkable biological catalysts enable the creation of outstanding solar fuel devices?), and of producing systems that serve as benchmarks and inspiration for the development of fully synthetic systems that are robust and scalable.
30
Mubarak, Kamakshi N. "Everyday networks, politics, and inequalities in post-tsunami recovery : fisher livelihoods in South Sri Lanka." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:6140f40d-9b68-4148-b62e-a3d8d9bdc646.
Full textAbstract:
The aim of this thesis is to explore how livelihoods are recovering in the aftermath of the 2004 tsunami in Sri Lanka through the lens of the Sustainable Livelihoods Framework and the social networks approach—methods of inquiry that have gained considerable impetus in livelihoods research. The study is conducted with reference to two tsunami-affected fisher villages in the Hambantota District, Southern Province. It employs a qualitative ethnographic methodology that examines narratives emerging from households, local officials of government and non-government organizations, office bearers of community-based organizations, local politicians, village leaders, and key informants. Focus is on evaluating how particular roles, activities, and behaviour are given importance by these groups in specific post-tsunami contexts and how these aspects relate to broader conceptualizations of social networks, informal politics, social inequality, and ethnographic research in South Asia. The findings support four major contributions to the literature. First, social networks are significant as an object of study and a method of inquiry in understanding livelihoods post-disaster. Second, paying heed to varied forms of informal politics is critical in post-disaster analyses. Third, the concept of intersectionality can extend and improve upon prevailing approaches to social inequality in disaster recovery. Fourth, ethnographic research is valuable for understanding everyday networks, informal politics, and change in South Asia. Collectively, these findings present a human geography of post-tsunami livelihoods in Sri Lanka, where networks, politics, and inequalities, which form an essential part of everyday livelihoods, have been reproduced in disaster recovery. The thesis constitutes a means of offering expertise in the sphere of development practice, highlighting internal differentiation in access to aid as a key issue that needs to be identified and systematically addressed by policymakers and practitioners.
31
Lantschner, Patrick. "The logic of political conflict in the late Middle Ages : a comparative study of urban political conflicts in Italy and the southern Low Countries, c. 1370-1440." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:88345337-bad5-4eb6-b626-ec6ae003cfef.
Full textAbstract:
This thesis examines urban political conflict in the late Middle Ages (c. 1370-1440) in Europe’s most heavily urbanised regions, Italy and the Southern Low Countries. Conflicts have frequently been viewed in the context of an emerging state-controlled political order, and have been interpreted either as forms of disruptive disorder, or as affirmations of political processes shaped by states. This thesis suggests that urban conflict should be studied not in the context of a state-controlled political order, but within the political framework provided by the numerous semi-autonomous jurisdictional institutions inside and outside cities (such as guilds, parishes or contending outside powers). This pluralistic order of politics gave rise to a form of political order sui generis which expressed itself in two ways. According to a general logic of conflict (Part One), particular rationales for justifying conflict (Chapter One) and specific political practices ranging from concealed protest to urban warfare (Chapter Two) were embedded in this multi-faceted and shifting political framework. Action groups could be negotiated and renegotiated around the resources provided by the city’s multiple legitimating institutions (Chapter Three). At the same time, such political institutions were configured differently in different cities, and this also generated a particular logic which lay at the basis of different systems of conflict (Part Two). Levels of conflict could, in fact, vary greatly between Bologna and Liège (Chapter Four), Florence and Tournai (Chapter Five), and Lille and Verona (Chapter Six), where, on the basis of different underlying political institutions, diverse practices of conflict and forms of association prevailed. The pluralistic order of politics itself was, therefore, a form of political organisation which crystallised around conflict. It gave rise to a logic which put conflict at the centre of the political order of late medieval cities.
32
Dodan'Li, Nihal. "Digital product labels and the mapping of consumer values." Thesis, Abertay University, 2013. https://rke.abertay.ac.uk/en/studentTheses/c697b0fe-d3e3-4f9a-b625-241cd3239b2b.
Full textAbstract:
Current labels of consumer products provide some level of information to consumers but at the moment, this expanding labelling logic, and the multitude of requirements it generates, is often tricky to implement and difficult to translate into a clear and accessible form of communication for consumers to engage with. In the first part of the thesis, an analysis of current labels is carried out which examine a selection of widely used consumer products. This examination supports the objective to imagine the type of complementary information consumers may deem useful, and also highlights the difficulty there may be for consumers in accessing and verifying some key information that directly concerns the product they use and that may significantly influence the assessment they make of it. To improve the quality of the information provided to the public, a fourtiered architecture is proposed in the second section that can respond to the issues that have been identified during the analysis and also with reference to techno-sociological considerations presented in the Literature Review. The end result is an online database which generates real-time digital labels that uses collaborative logics and allows users to conveniently explore essential information about the products and services they use and make decisions more in accordance with their own requirements and values. The system also offers the possibility for the various label stakeholders to actively engage with the evolution of the product they manufacture, verify, legislate upon or consume depending on their relation to the product. In order to illustrate the potential of this architecture, the digital label is applied to informational situations commonly encountered by consumers. Conceptually, the digital label appears capable to meet consumer needs and is ready to be implemented into a prototype. The architecture is also considered against recent developments in terms of digital product labels, and appears to offer a solid foundation to catalogue, compare and analyse them critically. The third section of the dissertation is a reflection on the merits of the digital labelling system, this time from a sociological perspective. The discussion has two objectives (1) validating the digital label as an information arrangement capable of responding to current societal demands and (2) determining the label underlying principles in order to guide further development.
33
Sokolova, Antoaneta Y. "Nitroaromatic pro-drug activation and resistance in the African trypanosome." Thesis, University of Dundee, 2011. https://discovery.dundee.ac.uk/en/studentTheses/52c1537e-4a37-446c-b62c-86df5b95b2ea.
Full textAbstract:
Sleeping sickness, caused by Trypanosoma brucei, is a deadly disease that affects some of the poorest countries in sub-Saharan Africa. Although the disease prevalence is declining, strengthening of the current control efforts, including introduction of more adequate chemotherapeutic options, is needed to prevent the re-emergence of yet another epidemic. Nitroaromatic compounds, such as nifurtimox (in combination with eflornithine) and fexinidazole (in clinical trials), have been recently introduced for the treatment of the second stage of sleeping sickness. These compounds are believed to act as pro-drugs that require intracellular enzymatic activation for antimicrobial activity. Here, the role of the bacterial-like nitroreductase TbNTR as a nitrodrug activating enzyme is examined through overexpression and knock-out studies in T. brucei. Multiple attempts to purify soluble recombinant TbNTR from E. coli were unsuccessful, because the recombinant protein was found to be membrane associated. In keeping with the role of TbNTR in nitrodrug activation, loss of an NTR gene copy in T. brucei was found to be one, but not the only, mechanism that may lead to nitrodrug resistance. Furthermore, in the bloodstream form of T. brucei, resistance was relatively easy to select for nifurtimox, with no concurrent loss of virulence and at clinically relevant levels. More worryingly, nifurtimox resistance led to a decreased sensitivity of these parasites to other nitroaromatic compounds, including a high level of cross-resistance to fexinidazole. Conversely, generation of fexinidazole resistance resulted in cross-resistance to nifurtimox. Should these findings translate to the field, emerging nitrodrug resistance could reverse all recent advances in the treatment of sleeping sickness, made since the introduction of eflornithine 20 years ago. Therefore, all efforts should be made to ensure nitroaromatic drugs are used only in drug combination therapies against sleeping sickness, in order to protect them from emerging resistance.
34
Albtoosh, Amal Aqeel Odeh. "Prediction of naso-labial morphology from dental pattern assessments." Thesis, University of Dundee, 2016. https://discovery.dundee.ac.uk/en/studentTheses/aca9f6fc-3259-4c54-b629-3734db89ee51.
Full textAbstract:
This project aims to develop standards to predict vermillion border shape and appearance - i.e. the outline of the vermillion border and the fullness of lips, based on assessment of an individual dental pattern using a combination of three methods: morphological, cephalometric and GMM. This study tests a hypothesis that the skeletal and dental pattern in antero-posterior and vertical dimensions and the upper and the lower incisor inclinations can predict the morphology of the soft tissue of the lips. This hypothesis was examined by analysing retrospective facial data, which consists of two-dimensional, pre-orthodontic treatment photographs and cephalograms of individuals of four malocclusion classes: Class I, Class II: divisions 1 and 2, and Class III from two sample populations: 56 Scottish and 56 Jordanians, aged 11-14 years. All the Scottish participants had been recipients of treatment at the Dental Hospital at the University of Dundee, and the Jordanian sample were selected from the Orthodontic archive held by Jordan University Hospital. The results reveal that a cephalogram analysis offers a statistically significant correlation differing from one type of malocclusion to another, in addition, analysis of cephalograms showing the value of angles and linear dimensions differed from one type of malocclusion to another. Photographic analysis using GMM afforded a statistically reliable correlation between naso-labial traits, and particularly between the vermillion border outline and malocclusion patterns. Due to their shared ancestry (Caucasian), both Jordanian and Scottish populations showed the same morphological trends for the lips, for example: long lower facial height, a deep philtrum, V-shaped Cupid’s bow, thin upper vermillion border. GMM results suggest that vermillion border variation could be computed, at least when distinguishing between malocclusion classes from the same ethnic group. Morphological, GMM, and cephalograms analyses confirmed that the shape and diversity in the Vermillion XIV border outline differed between malocclusion classes, but few or no differences could be shown between the sexes.
35
Tahat, Yasean A. "The usefulness of Financial Instruments Disclosure : evidence from Jordan." Thesis, University of Dundee, 2013. https://discovery.dundee.ac.uk/en/studentTheses/15559e90-b670-4cc5-befd-e9ba60e60bda.
Full textAbstract:
The International Accounting Standards Board (IASB) issued International Financial Reporting Standard No. 7 (IFRS 7) “Financial Instruments: Disclosure” in June 2006 as part of its ongoing refinement of existing financial instruments accounting standards. The new standard became effective for periods beginning on or after January 1st 2007 (IASB, 2006). IFRS 7 supersedes the previous International Accounting Standards (IASs): IAS 30/32. IFRS 7 states that information about Financial Instruments (FI) should be prepared in accordance with the management approach. In addition, the standard clarifies the disclosure requirements about FIs across all industries. In particular, the new standard consists of two main types of disclosures, namely: (i) discussion of the significance of FIs for an entity’s financial position and performance; and (ii) the provision of qualitative and quantitative information about exposure to risks arising from FIs based on information provided internally to the entity’s key management personnel. The current thesis uses a decision usefulness theoretical framework to examine the impact of IFRS 7’s adoption on FI disclosure practices and firm value. In particular, the current study has two primary objectives: (i) to assess the impact of IFRS 7 on the FI disclosure policies of Jordanian listed firms in their annual reports for 2007 when the standard became effective; and (ii) to examine the value relevance of FI disclosures. For these objectives, two pieces of empirical work were conducted respectively; a disclosure index technique was constructed and a valuation analysis was performed. A disclosure index analysis was undertaken for a sample of Jordanian listed companies’ annual reports pre- and post- the implementation of IFRS 7. The extant literature and the findings from the disclosure index analysis informed the second part of the empirical work: the valuation analysis. Value relevance analysis was employed in order to assess the usefulness of FI disclosures provided in the companies’ financial statements; indeed, the association between the level of information supplied and firms’ market values was examined. The main findings indicate that the implementation of IFRS 7 had a significant and sizeable impact on the FI disclosure practices of Jordanian companies in 2007 as compared to that provided under International Accounting Standard No. 30 (IAS 30): Disclosures in Financial Statements of Banks and Similar Financial Institutions and International Accounting Standard No. 32 (IAS 32): FIs: Presentation. In particular, the results revealed that the number of companies disclosing information about FIs as well as the level of FI information provided significantly increased after IFRS 7 was implemented. In addition, the analysis of FI disclosure by industry revealed that comparability of financial statement data within and across the sectors examined has improved. In particular, an analysis of Balance Sheet and Fair Value information about FIs revealed no significant differences within and across industries after IFRS 7 became effective. The findings from the valuation analysis revealed that FI disclosure was value relevant over the two periods. However, the regression analysis showed that the FI disclosure provided under IFRS 7 was more value relevant as compared to that supplied under the previous standards. The principal components analysis revealed that some categories of FI information were more influential than others. In particular, Balance Sheet, Income Statement, Fair Value and Risk information about FIs were valued differently as compared to other components of FI disclosures. Indeed, the evidence provided indicates that investors value FI disclosure when making investment decisions. In general, the findings support the decision usefulness approach underpinning the current FI disclosures for Jordanian listed companies. Specifically, In particular, the test of differences in FI disclosure within and across sectors revealed that the implementation of IFRS 7 has enhanced the comparability of the financial statements; no significant differences were noted in FI disclosure (balance sheet and fair value) post-IFRS 7, while this was not the case pre-IFRS 7. In addition, the issue of relevance has been investiagted by testing the association between FI disclosure and firm value. These findings provide a great deal of insight for accounting regulatory bodies (e.g. the IASB) about the current theoretical framework that underpins financial reporting standards. In addition, they provide valuable insights to Jordanian policy makers (JSC and ASE) about the relevance of such standards for Jordanian companies.
36
Corbishley, Stephen J. "An investigation into Cdc28 phosphorylation of Ipl1 and the role of Haspin-like kinases in yeast cell cycle control." Thesis, University of Dundee, 2013. https://discovery.dundee.ac.uk/en/studentTheses/b5a37307-cf0f-43b3-b625-cabcc40bb404.
Full textAbstract:
The chromosomal passenger complex (CPC) is a conserved, essential protein complex in eukaryotes, consisting of Ipl1/Aurora B kinase and three regulatory subunits: Sli15/INCENP, Bir1/Survivin and Nbl1/Borealin. The CPC has numerous cell cycle roles, the best characterised of which is the regulation of kinetochore-microtubule attachments during metaphase to promote chromosome bi-orientation on the mitotic spindle. To efficiently perform these functions, the CPC must be properly regulated and localised. The original defining characteristic of 'chromosomal passenger' proteins was their dynamic localisation: associated with chromatin and centromeres during early mitosis followed by translocation to the spindle midzone during anaphase. However, exactly how the CPC is properly localised and regulated is not fully understood. Recent studies demonstrated that phosphorylation of the CPC regulatory subunits by cyclin-dependent kinase (CDK) regulates localisation of the complex. For example, in budding yeast and human cells the dephosphorylation of CDKphosphorylated sites in Sli15/INCENP is required for the efficient translocation of the CPC from centromeres in metaphase to the spindle in anaphase. Many Ipl1/Aurora B homologues also contain CDK phosphorylation motifs but whether modification of these sites is required for proper CPC localisation and function is not known - here this was investigated in budding yeast. Preventing phosphorylation of CDK consensus sites in the N-terminus of Ipl1 was found to result in its premature localisation to the spindle in metaphase; this was dependent on the yeast microtubule binding EB1 homologue Bim1. However, preventing or mimicking phosphorylation at these sites had no effect on cell viability or chromosome bi-orientation. During the course of this study, several groups demonstrated that the conserved Haspin kinase in fission yeast, Xenopus and human cells contributes to CPC localisation at the centromere during metaphase by phosphorylating histone H3 on Threonine 3 (H3- T3). In light of these findings, two budding yeast Haspin kinase homologues (Alk1 and Alk2) were investigated. Although roles for Alk1 and Alk2 in histone H3 phosphorylation and CPC recruitment could not be conclusively determined, unusual phenotypes were observed in cells lacking both Alk1 and Alk2. In these cells, the spindle was frequently confined to the bud and incorrectly aligned. If these cells were arrested in metaphase, the bud became significantly larger than the mother cell. When anaphase was eventually triggered, the spindle elongated and then broke down entirely within the bud. These abnormalities were independent of histone H3-T3 phosphorylation, since mutation of H3-T3 to non-phosphorylatable alanine did not result in these phenotypes. Thus Alk1 and Alk2 share novel and redundant roles in spindle positioning, cell polarity and bud growth that are particularly important during a metaphase arrest.
37
Galli, Lucia Maria Sara. "The accidental pilgrimage of a rich beggar : the account of tshong dpon Kha stag 'Dzam yag's travels through Tibet, Nepal, and India (1944-1956)." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:28e5ea72-794c-443e-b626-651a71a0974a.
Full textAbstract:
The Tibetan literary corpus offers a wide array of (auto)biographical accounts; Tibetans have been recollecting - and narrating - life stories in earnest since the "later diffusion" (Tib. phyi dar) of Buddhism in the 11<sup>th</sup> century. The hybrid essence of life writing, suspended between fact and fiction, finds a perfect expression in the text at the core of the present dissertation, i.e. the journal (Tib. nyin deb) of a 20th century Khams pa trader, Kha stag 'Dzam yag. The text records the events, travels, and impressions experienced by the author between 1944 and 1956; structured like a diary, this autodiegetic text, originally written in a scroll-paper format, was later edited and finally published in India in 1997. Two different heuristic devices, i.e. narratology and socio-economic analysis, are used in the present dissertation to analyse the structure and content of the nyin deb, as well as the author's idiosyncrasies emerging from the process of narrativisation. Whereas the narratological approach allows the identification of the interplay of memory, self, and culture in the socio-historical context of mid-20th century Tibet, the socio-economic analysis reflects on the nyin deb as a form of social history rather than personal narrative. The identification of "true", historical facts confirms the author's claims to factuality, thus providing unique information and insight regarding the political and economic role of Khams pa traders in 1940s-1950s Tibet, as well as the development of new pilgrimage rituals and the emergence of forms of "spiritual tourism" in modern India.
38
Khan, Muhammad Abdullah. "Carbon nitride based materials for heterogeneous photocatalysis." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:8498a9f5-e5c8-4eda-b62d-0cd36471759c.
Full textAbstract:
Photocatalysis on semiconductor surfaces has grown tremendously in the last four decades. One reason for this is its analogy with photosynthesis, the most important natural photochemical process. Semiconductors to some extent can mimic the key steps of this fascinating heterogeneous photocatalytic process, i.e., photochemical charge generation, charge trapping, interfacial electron exchange and subsequent reaction. Building on this premise this thesis constitutes an investigation into the photocatalytic properties and applications of semiconducting layered framework carbon nitride based materials. Similar to traditional photocatalysts, the photocatalytic activity and efficiency of carbon nitride systems developed thus far is limited mainly by the fast recombination and low mobility of photogenerated excitons. Here, by exploiting the band alignment strategy, carbon nitride isotype (type II) and carbon nitride-niobium oxide of type II semiconductor heterojunctions were successfully constructed with the aim of suppressing the exciton recombination and improving charge extraction for the successful initiation of desirable redox chemistry. These features were demonstrated by employing the materials in heterogeneous photocatalysis for water splitting, organic pollutant decomposition and photochemical organic synthesis. Carbon nitride isotype heterojunctions constructed by controlled thermal condensation are shown to exhibit lower recombination of excitons relative to the pristine carbon nitride. As a consequence photocurrent generation and visible light driven H2 production activity was enhanced. This increase is attributed to the surface passivation and improved electron mobility of built-in electric field which arises from the topology-induced band offset of favoured type II heterojunction configuration. Building on the insights into the heterojunction-activity dependence, new type II graphitic carbon nitride (C3N4), Nb2O5 (C3N4-Nb2O5), heterojunctions synthesised via a hydrothermal method were exploited for their photodegradation ability of the organic pollutants. The synergic effect of carbon nitride and Nb2O5 coupling leads to the substantial photocatalytic activity improvement which can be attributed to the formation of an intimate interface and gradual attenuation of energy-wasteful charge recombination processes in C3N4-Nb2O5 heterojunctions materials. While water splitting and pollutant decomposition using semiconductors has received the bulk of attention, the possibilities concerning chemical synthesis are only beginning to be meaningfully exploited. We, therefore, employed carbon nitride to catalyse photo organic synthesis. It was demonstrated for the first time that carbon nitride can efficiently catalyse the photoacetalization reactions of aldehydes/ketones with alcohols, forming acetals at high yields using visible light under ambient conditions. Mechanistic studies suggest that the transient charge separation at the surface of this material is sufficient to catalyse the reaction in the absence of Lewis or Brønsted acids or solvent systems. Since the photoacetalization of aldehydes occurs under conditions similar to those of alcohols oxidation, both using visible light and carbon nitride as a catalyst, the two reactions actually proceed via different mechanisms. This study also demonstrates, visible light induced heterogeneous auto-tandem catalysis, coupling the oxidation and subsequent acetalization of alcohols in a single chemical process. This green strategy can be applicable to a wide variety of organic photo-induced synthesis.
39
Yung, Nancy. "The right to be killed : reassessing the case for the moral right to voluntary active euthanasia." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:2aa54686-b621-4323-b836-ce6099b5d2fd.
Full textAbstract:
This thesis defends an individual's moral right to be aided in dying by a physician (that is, voluntary active euthanasia, or VAE), but departs significantly from the view in its favor generally accepted in the bioethics literature. The prevailing view appeals to both respect for an individual's autonomy and promotion of an individual's well-being as necessary conditions for a right to VAE, so as to justify the right only for those suffering grave illnesses and/or disabilities. The author argues that such a view is logically untenable; one or another aspect must be given up. Since invoking the premise that certain individuals would be better off dead necessarily relies on controversial assumptions about both the value of life and the nature and value of death, about which reasonable people disagree, it is the justification from an individual's best interest which must be excluded in a liberal society. The author endorses a self-determination justification for the right to VAE, but rejects understanding this in terms of respecting personal autonomy, instead making the case for a right to VAE grounded in self-ownership. The author's main conclusion is that the right to VAE is a general right applying to all competent adults, not only those suffering grave illnesses or disabilities, or those whose choice for VAE is an exercise of autonomy. Moreover, by analyzing the basis of physician authority over prescription medicine and how this can be justified to a society of self-owners, she maintains that individuals have not only the right to choose VAE without state interference, but also the right to be provided VAE by doctors. Nevertheless, both rights are compatible with reasonable limitations to protect both the interests of VAE seekers and the rights of others.
40
Mao, Yuanbo. "The Rose playhouse in context." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:86467c23-e16b-4ee4-b625-c8deea5cd491.
Full textAbstract:
This thesis conducts the first book-length study on the operation of the Rose playhouse as a key theatrical presence whose operational history spanned over a transitional period for early modern English theatre. Inspired by the current increasing awareness of the playing company as an organising unit in additional to the author-based perspectives for studying early modern English drama, this project undertakes the task of examining the Rose playhouse as a unit for theatrical production and a nexus where various strands of the material, cultural-geographical, political, financial, as well as literary forces converged and interacted with each other.
41
Battis, Matthias. "Aleksandr A. Semenov (1863-1958) : colonial power, orientalism and Soviet nation-building." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:8c290939-3662-4204-b670-881028aecfae.
Full textAbstract:
This study explores the life of the prominent Russian Orientalist and colonial administrator Aleksandr Semenov (1873-1958). In the course of his long and versatile career in Central Asia - where he came to in 1901 as a low-ranking member of Turkestan's colonial administration, and where he died in 1958 as the first director of the Institute of History, Archaeology and Ethnography of Tajikistan's Academy of Sciences - Semenov participated in the transformation of the region from a Tsarist colony into part of what Francine Hirsch has called an 'Empire of Nations'. His influence on national historiography and notions of national identity was especially marked in the case of the Soviet Union's only Persian-speaking republic, Tajikistan, with which Semenov was connected through his interest and expertise in Persianate Central Asia. This thesis even goes so far as to argue that Semenov's scholarship and his work as an advisor to the Soviet government facilitated the very establishment of Tajikistan, which Paul Bergne has described as a nation initially promoted by Russian Orientalists. Further research in Russian archives is required, however, to better substantiate this claim. Rather than focussing on the (early) Soviet period and on so-called national territorial delimitation of Central Asia, as scholars such as Hirsch and Arne Haugen have done, the present study, in the vein of scholars like Vera Tolz and Vladimir Genis, highlights the ways in which both Bolshevik nationalities policy and Soviet Oriental Studies grew out of the studying and ruling of Central Asia in the late imperial period. It does so through an examination of Semenov's career, scholarship and personal networks, and on the basis of his personal archive in Tajikistan's Academy of Sciences, which has not been researched in any systematic way since the early 1970s, and in which no scholar from outside the former Soviet Union has ever worked.
42
Kapellos, Theodoros. "Critical assessment of the role of cannabinoid receptor 2 in inflammation." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:23d8a031-ac0c-4c07-b670-8cabfeb1a251.
Full textAbstract:
Cannabinoid receptor 2 (CB2R) is a G protein-coupled receptor (GPCR) expressed in the periphery by immune cells, such as B cells, natural killer (NK) cells, neutrophils, macrophages and T cells. It belongs to the endocannabinoid system which also comprises CB1R, endogenous lipophilic agonists called endocannabinoids and the enzymes responsible for their synthesis and degradation. During inflammatory diseases the endocannabinoid system is dysregulated and increased expression levels of endocannabinoids and cannabinoid receptors are observed. Therefore there is a continuing interest to target the endocannabinoid system to restore homeostasis in patients who suffer from a number of inflammatory diseases, such as multiple sclerosis, atherosclerosis, neuropathic pain and others. However, to date there has been no good anti-inflammatory drug in the market or clinical trials that acts via CB2R. The main aim of this DPhil thesis was to critically assess the role of this receptor in health and inflammation with a particular focus on innate immune cell recruitment. Here I describe my findings regarding the immunophenotype of a CB2R knockout (KO) mouse strain at steady state and under acute systemic inflammation. I showed that CB2R KO mice display a trend in neutrophil accumulation and in monocyte egress in the bone marrow, as well as higher myeloperoxidase activity in the liver. These findings support the view that this cannabinoid receptor plays a pivotal role in innate immune cell trafficking during homeostasis. Furthermore, I discovered that CB2R KO animals display exacerbated immune cell recruitment to peripheral tissues in a model of low dose endotoxemia. In particular, I found more neutrophils in the lungs and spleens of CB2R KO mice at the model's peak time point. These observations are consistent with a model in which CB2R plays a non-redundant role in the inhibition of neutrophil migration to injured tissues after an inflammatory insult. My in vitro experiments showed that CB2R-selective agonists had no anti-inflammatory effects during macrophage activation. Looking for a mechanistic explanation for this result, I found that the expression levels of the receptor are severely downregulated upon challenge with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) which suggests that it is possible that CB2R is differentially regulated in immune cells during inflammation. Collectively, the data presented in this thesis support the view that CB2R plays an important role in health and disease in pre-clinical models, but further studies are required to make more soluble CB2R-selective agonists and to understand which immune cells we should aim to target therapeutically.
43
Mahadi, Abdul Hanif. "Ceria morphologies as Pd nanoparticles support for heterogeneous catalysis." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:8c0e2576-b6a0-4fa6-b7a1-be59431fc3d8.
Full textAbstract:
Ceria is well known for its unique properties in fast oxygen mobility and formation of oxygen vacancies which makes ceria an excellent catalyst support for metal nanoparticles. Promotional effect of ceria has been well established in a number of reactions including three-way catalyst and CO oxidation. These unique properties of ceria are dependent on the surface facets it exposes, where they can be enhanced by the exposure of high energy surfaces such as (100) and (110). The work presented in this thesis involves controlling the surface exposed by the ceria support by making them into cube and rod morphology, which predominantly expose the (100) and (110) surface, respectively. Hence, the effect of these surfaces on the ceria support can be investigated. The ceria morphologies were deposited with Pd nanoparticles and their catalytic properties were tested on methane combustion and gas-phase formic acid decomposition reactions. In both of the catalyst test reactions, the Pd deposited on the ceria cubes support had shown superior catalytic properties compared to the Pd deposited on the ceria rods support, indicated by the former's higher activity, TOF and resistance to poisoning. Based on the characterisation techniques performed in this study such as TPR, ambient pressure XPS, STEM-EELS and pulse isotopic oxygen exchange, the enhanced catalytic properties of Pd/ceria cubes were attributed to the high energy ceria (100) surface which led to more favourable formation of oxygen vacancies and faster oxygen mobility.
44
Oxley, Natasha Emma Fortescue. "Talking taboos: the personal over the political? : contemporary Polish playwriting : theme and dramatic technique in selected modern Polish plays." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:036a5a0e-aa99-40f9-b610-4a267bc1e533.
Full textAbstract:
The focus of this thesis is contemporary Polish playwriting after Poland's accession to the European Union in 2004. From a broad reading of plays by many new writers, four playwrights were selected for study on the basis of prominence and artistic merit: Pawel Demirski, Dorota Maslowska, Malgorzata Sikorska-Miszczuk and Przemys law Wojcieszek. Their plays were studied as texts and in performance, and twelve main plays became the focus of closer analysis. The thesis identifies and examines three major concurrent themes in the works of these playwrights. Remembering versus forgetting the past is discussed through the lens of selected aspects of memory studies, including Nora's lieux de mémoire, Hirsch's postmemory and Assman's mnemohistory. The playwrights are shown to share an endorsement of the de-politicisation of collective memory and to advocate a cessation of the passing down of trauma to post-war generations. The human body is highlighted as another concurrent thematic concern and is illuminated by certain tenets of Catholic doctrine as well as Merleau-Ponty's phenomenology. The playwrights' rejection of the tabooisation of the body is demonstrated and the shared notion of the body as both sentient and unifying is exemplified. Social marginalisation is examined as the final concern, with an emphasis on the notion of the 'other', particularly in relation to socio-economic status, sexuality, and religious beliefs. The plays are shown to support and promote a rejection of the myth of homogeneity in favour of openness to diversity. Major dramatic techniques are then closely examined. It is demonstrated that the plays share traits with Lehmann's theory of postdramatic theatre, including a rejection of Aristotelian unities. Key commonalities are evidenced, particularly comedy, bad language, intertextualities with the outside world, and an engagement with Polish social realities. The playwrights' approach to the spectator as a socio-political being is shown to be of paramount importance.
45
Che, Omar Sarena. "Investigating the role of the Crh gene family in Magnaporthe oryzae on cell wall integrity and fungal virulence." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:85092357-b629-46b7-b5f0-a61ae2444198.
Full textAbstract:
The rice blast disease caused by the fungus Magnaporthe oryzae causes significant annual crop losses of up to 30%. The fungal specific cell wall is a potential antifungal target due to the external location and importance to fungal survival and morphogenesis. The skeletal framework of the cell wall is made from glucan chains cross-linked with chitin, facilitated by the Congo Red Hypersensitivity (Crh) enzyme. In Saccharomyces cerevisiae, ΔCrh1/ΔUtr2 mutants exhibit reduced wall integrity and the same is observed in Candida albicans, with reduced virulence in a mammalian host. Little is known about the cell wall in fungal plant pathogens and nothing of the Crh orthologs. Bioinformatics revealed five M. oryzae Crh-like genes lying in two clades. Gene expression analyses revealed up to four-fold elevated expression of MGG_Crh2 and MGG_Utr2 when grown under cell wall stress. Consistently, the corresponding deletant strains showed hypersensitivity towards cell wall perturbants and was attributed to a loss in cell wall rigidity. Cell wall analysis of the mutant ΔΔMGG_Crh2_Utr2 revealed changes in the cell wall composition consistent with the reduction of Crhp activity and activation of cell wall compensatory mechanism often observed in a compromised cell wall. Furthermore, eGFP-tagged MGG_Crh2p showed localisation to the lateral cell wall with high accumulation at septum and polarised growth sites, consistent with sites of chitin accumulation. These mutants are, however, able to form normal infective structures and are fully pathogenic on susceptible rice cultivars. In conclusion, the Crh gene family in M. oryzae is important for cell wall integrity by the cross-linking of chitin to glucan, but dispensable for virulence. Future work should explore the compensatory mechanism of other cell wall proteins in the ΔΔMGG_Crh2_Utr2 as this could shed light on the potential for targeting multiple cell wall components in a synergistic approach to confer effective disease control.
46
Bird, Geoffrey R. "Tourism, remembrance and the landscape of war." Thesis, University of Brighton, 2011. https://research.brighton.ac.uk/en/studentTheses/ac43bbe6-9b32-4211-b62c-ef897b0899e3.
Full textAbstract:
The aim of this thesis is to examine the relationship between tourism and remembrance in a landscape of war, specifically the Normandy beaches of World War II where the D-Day Landings of June 6, 1944 took place. The anthropological investigation employs a theoretical framework that incorporates tourist performance, tourism worldmaking, landscape, cultural memories of war and remembrance. The thesis also examines the tourism-remembrance relationship by way of the various vectors that inform cultural memory, such as the legend of D-Day, national war mythologies and war films, and how these are interpreted and refashioned through tourism.
47
Ajzensztejn, Daniel. "Harnessing the immune system to reject cancers through genetic modifications of tumour cells." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:1aafa1f4-ee10-4081-b621-d81b9979d96a.
Full textAbstract:
The immune system, which defends the body against a wide array of threats, is gaining a growing role in the fight against cancer. For an immunotherapy to be successful, it needs to overcome intrinsically weak tumour-specific immune responses. There are two broad approaches to achieving this goal: targeting the various arms of the immune system or targeting the cancer and its microenvironment. The experiments discussed in this thesis adopt the second approach. Tumours were transduced with a combination of costimulatory molecules: CD48, CD54, CD70 & CD86, the chemokine CX3CL1 and the cytokines: IFNγ, GM-CSF and IL-12. Transduction of costimulatory molecules enhances priming in-vitro and cause tumour rejection and delayed tumour growth in-vivo. This effect is demonstrated with single costimulatory molecules but is more pronounced when multiple costimulatory molecules are transduced. Addition of the cytokines and chemokine enhanced tumour rejection, and also resulted in partial rejection of contralateral parental tumours. Attempts to enhance anti-tumour memory by fusing IL-2 and IL-15 to their respective receptors are also discussed. Work in a human/mouse chimeric PD-1 mouse model shows that transduction of multiple costimulatory molecules is able to overcome intrinsic anti-PD-1 resistance. Radiation is known to result in upregulation of several costimulatory molecules within tumours or their infiltrating dendritic cells. The experiments presented here suggest that radiation therapy may be useful in overcoming anti-PD-1 therapy resistance. In human trials, approximately three quarters of cancers fail to respond to anti-PD-1 therapies. Understanding and potentially overcoming anti-PD-1 therapy resistance is therefore of great interest.
48
Polymeropoulou, Marilou. "Networked creativity : ethnographic perspectives on chipmusic." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:2c16d1ac-10c8-4493-b624-ebe5be41c9f4.
Full textAbstract:
This thesis examines creativity as manifested in an online and transnational network of musicians who compose chipmusic, a kind of electronic music characteristic of 1980s early home computers and videogame sounds. The primary argument is that creativity in chipmusic worlds is networked, meaning that it is dispersed across various activities that are labelled as creative: chipmusic-making, technology-hacking practices that underpin the music, digital cultural practices such as use of social media, online releases, crowdsourcing, staged and screened performances, and any other activity related to chipmusic. The thesis examines the ways in which networked creativity is mediated in the chipscene from an interdisciplinary methodological viewpoint informed by ethnomusicology, anthropology, and sociology. Although the chipscene is geographically dispersed across more than thirty countries worldwide, the chipscene network is well-connected. Communication and music circulation practices of chipmusicians are enabled by the internet. This thesis primarily discusses chipmusic culture that suggests a rich context where creativity discourse is as intensely diverse as the chipscene itself, in which it is embedded. In looking at the creative process and performance practices, I employ a mixed methods approach based on ethnographic research methods and social network analysis, to examine how intrinsic and extrinsic aspects of chipmusic-making, such as ideology, cultural values, network infrastructure, chiptune poetics and aesthetics, distribution of creative roles, authenticity, differentiation, genre dynamics, and intellectual property issues, shape creativity.
49
Khanfar, Nehad. "A comparative critical analysis of the concepts of error and misrepresentation in English, Scottish, Islamic, international contract law, and Palestinian draft civil law." Thesis, Abertay University, 2010. https://rke.abertay.ac.uk/en/studentTheses/577cbdf3-2be9-4856-b623-5183bc88057e.
Full textAbstract:
Although the laws of error and misrepresentation have a decisive impact on contract and contractual relationship, existing studies of Islamic jurisprudence, and the CISG have occasionally discussed or considered these fundamental topics. These legal systems do not assume the obvious approach found in comparison with their counterparts, English and Scottish contract laws, which form independent and comprehensive concepts in their legal research and argument. This thesis fills the gap in the literature by a comparative, critical analysis studying error and misrepresentation in Islamic contract law and the CISG, with the purpose of developing these concepts based on English and Scottish contract law in general and English law in particular as the main guidance, from which the organisational structure is derived for clear definitions of the categories of error and misrepresentation. This thesis investigates the linguistic and historic streams of the concept of error and misrepresentation in Islamic contract law “relying on the Qur’anic context”, thus creating entirely different approach to both concepts, and giving further guidance to other researchers to develop and improve their view of these significant concepts. Based on the existing studies and theories, this thesis analyses and criticises in particular the views of English and Scottish law with respect to the categories of error and misrepresentation. At the same time, this study builds a new approach to the concepts of error and misrepresentation by analysing and criticising relevant case law arguments, and by synthesising some types of error. This thesis offers a thorough comparison especially between Islamic and English contract law. These views are designed to introduce the legal systems cited in this thesis closer to each other and will establish an interactive approach, especially between Islamic and English contract law. Therefore, this thesis establishes a new Islamic-Anglo approach to misrepresentation as a result of actual interactivity between these legal systems. As a result, the author of this thesis offers an extensive critical analysis of the concepts of error and misrepresentation in the Palestinian Draft Civil Law, producing academic recommendations to be taken into consideration by its draftspersons. These recommendations can also be applied to Egyptian and Jordanian civil law.
50
Cervelli, Filippo. "Ima deshō : the vacuum of immediacy in contemporary Japanese literature and popular culture." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:521d5f5e-d34d-454a-b622-a0454783cf80.
Full textAbstract:
The value of literature in the contemporary age is a controversial issue. The challenge posed by the interpretation of this era is expressed by the provocative remarks of critics such as Karatani Kōjin and Suzuki Sadami maintaining that after the 80s modern "pure" literature died (History and Repetition, 2012; The Concept of "Literature" in Japan, 2006). Reading Karatani and Suzuki's comments as merely provocative, signifying that a form of literature has died, this study enquires into how literature (and the arts) have changed and found new ways of expression after the historical break of 1989. The dissertation offers immediacy as a possible answer. Immediacy is a theme, a literary device stressing the present moment submerging clear notions of past and present. The precondition for immediacy is an ideological vacuum, experienced by characters across age groups and genders, where they do not share social ideologies or collective purposes. In this isolation, they concentrate only on their local realities, on what they perceive directly (physically and emotionally), acting quickly and repeatedly in the absence of critical thought. The constant action is often carried out in response to corporeal stimuli, specifically violence and sex, that grant immediate gratification in the vacuum. However, at the core characters indulging in immediacy long for inter-personal connections. Building a community based on critical thought and mutual understanding is the solution to escape from immediacy. The dissertation explores manifestations of immediacy in contemporary Japanese literature and popular culture (manga and anime) published or broadcast between 1995 and 2011. Through the analyses of cultural theories, literature by Takahashi Genichirō, Taguchi Randy and Hirano Keiichirō, and influential works in manga and anime (Neon Genesis Evangelion, Psycho-Pass and Shingeki no kyojin), it shows the theme's relevance and discusses how it contributes to the broader fields of contemporary Japanese literature and popular culture. By doing so, the dissertation also provides a study of the current artistic panorama in Japan, one that is often neglected critically, but that speaks of its culture with great force and imagination.