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Deliberation, Democracy, and Mechanisms for Cooperation
Get PDFThis thesis explores group decision-making and mechanisms to encourage cooperation through three experimental studies.
Study one uses a public goods game (PGG) with informal and formal sanction mechanisms to understand how team decision-making differs from individual decision-making in a democratic institutional setting. Teams consistently outperform individuals when sanctioning schemes are available, by selecting higher sanction rates when choosing the formal scheme and pro-socially targeting punishment toward low-cooperators when using the informal scheme. This improved decision-making appears to be a result of deliberation and has implications for using team decision-making to overcome moral hazards.
Building on this, study two examines team behaviour in a real effort experiment to understand the impact of democratic decision-making. Specifically, in one treatment teams may vote on whether to implement a policy that reduces the returns from free-riding within their group, while in the other treatment, this policy is randomly implemented. Teams exhibit significantly higher productivity when they are able to democratically decide whether to implement the policy, regardless of the vote outcome. While teams in these treatments also increase their time free-riding, the higher productivity compensates for this and so it does not harm overall production. As in the first chapter, this study highlights the benefits of autonomous team-decision making in improving cooperation.
Study three explores how a group may encourage cooperation to prevent a more costly problem in a two-stage PGG. Subjects complete real effort tasks that either reward them directly or improve the payoff schedule in the following stage, forming a second-order social dilemma. Free-riding does not dominate the pre-stage nor does cooperation decline as strongly as observed in other PGG, demonstrating how leveraging fewer resources to overcome related social dilemmas can make cooperation easier. Further, providing a simple cost- and ramification-free feedback mechanism considerably increases the level of cooperation observed
A Bayes Linear Analysis of Multilevel Models
Get PDFIn this thesis, Bayes Linear methods for modeling multilevel data are presented
and discussed. Second-order exchangeability judgements are exploited to formulate
subjectivist versions of multilevel models. Bayes linear methods are applied to
estimate model parameters and for diagnostic checks. Closed-form expressions of
estimators are derived, allowing insight into relationships between the quantities
thereof. The canonical analysis and resolution transforms are used to guide sample
design and sample size determination under cost constraints. A finite version of a
multilevel model is formulated, analysed and compared to infinite versions, giving
further insight into sample design issues via the finite resolution transform.
A new Bayes Linear Minimum Variance Estimation (BLIMVE) approach is de-
veloped to estimate variances. Estimated variances are used to perform two-stage
Bayes linear analysis of more complex multilevel models. The methods developed
are shown to be applicable in cases of small level-2 samples. The Bayes linear analy-
ses of multilevel models are applied to an educational data set using special-purpose
codes written in the R Statistical Language
An investigation into the role of Small Ubiquitin-like MOdifier (SUMO) in plant response to phosphate deficiency
Get PDFRice (Oryza sativa) is a staple food crop for more than half of the world’s population and provides 20% of dietary energy all over the world. Although it is the main source of calories, nearly 60% of rice is grown in soils which are low in phosphorus especially in Asia and Africa.
Inorganic Phosphate (Pi) is a non-renewable and indispensable macroelement for plant growth. Pi levels in soil are modulated by interaction with other elements such as aluminium and iron. This interaction between other elements regulates the availability of Pi to plants even after the application of fertilizers. Given the limitations of bioavailable Pi in soils, it is important to develop crops tolerant to low phosphate. This would be helpful to resource-poor farmers.
Due to their immobile nature plants have developed complex molecular signalling pathways that allows them to discern changes in the environment and adapt their growth and development. Post Translation Modifications (PTMs) play an important role in plants in providing a conduit to detect the changing environment and influence molecular signalling pathways to adapt growth and development. In recent years the PTM SUMOylation has been shown to be critical for plant growth and development. It is known that plants experience hyperSUMOylation of target proteins during stresses such as heat, salinity, drought and phosphate starvation. We provide new evidence for the role of SUMO in plant responses to Pi starvation. Here we demonstrate that PSTOL1 is SUMOylated in planta, and this affects its autophosphorylation activity. Moreover, we have investigated the targets of PSTOL1 using yeast two hybrid and coimmunoprecipitation techniques. Further, we also provide new evidence for the role of SUMO in plant responses to Pi starvation in rice and Arabidopsis. Our data demonstrated that overexpression of non – SUMOylatable version of OsPSTOL1 negatively affects the root parameters of rice grown under low Pi. Interestingly, our data also showed that overexpression of PSTOL1 in a heterologous system, Arabidopsis positively impacts overall plant growth under high and low Pi by modulating root system architecture.
Therefore, unraveling the role of SUMOylation to improve plants’ ability to survive in phosphorus-deficient soil will open-up new ways to enhance the productivity of rice varieties
Reading traumatic memory in Henri Dutilleux’s music
No full textThis thesis uses a hermeneutical approach to examine the ways the music of Henri Dutilleux engages with the trauma of the Second World War. It considers the composer’s work in its cultural context, and analyses it in relation to various literary and philosophical texts. Setting out in occupied France, it begins with an exploration of Dutilleux’s formative experiences as a composer. On the one hand, throughout this period, Dutilleux shows a commitment to various forms of musical resistance, most notably setting to music the poetry of prominent figures of the French Resistance, such as Jean Cassou’s Trente-trois sonnets composés au secret (1944). On the other, the especially complex circumstances of the Occupation saw Dutilleux working for the compromised broadcasting station Radiodiffusion nationale and composing the music for the Vichy propaganda film Forces sur le stade (1942). The composer’s dualistic profile typifies the reason why the processing of ‘the dark years’ (‘les années noires’) has proven particularly difficult in France. From Charles de Gaulle’s ‘resistancialist myth’ (‘mythe résistancialiste’) to François Mitterrand’s refusal to accept the French Republic’s responsibility during the Occupation, the nation’s double discourse of denial continued late into the twentieth century. It is therefore highly significant that Dutilleux’s Second Symphony, Le double (1959), should conceptually foreground duality. While its conformity to the Ars gallica ethos of re-appropriating the symphony establishes a dialectical opposition between its ‘traces of philosophy’ (‘traces de philosophie’) and its vestiges of the Beethovenian symphonic model, other features of Le double, such as the division of the orchestra into two distinct ensembles, symbolically evoke the phenomenological notion of split consciousness, which most markedly came to the fore in Jean-Paul Sartre’s philosophical investigations conducted during the Occupation. From a historical perspective, it also seems symbolic that Dutilleux should have waited until the end of the twentieth century before addressing Holocaust trauma in his composition The Shadows of Time (1997). This programmatic work responds directly to the nation’s ‘duty of memory’ (‘devoir de mémoire’) principle, and its anti-monumental character offers a striking re-enactment of the experience of trauma that comes to light through the Adornian notion of the aesthetic ‘breakthrough’
Obstetric Violence as a Civil Battery: Exploring the Limitations of Tort Law in the Context of Unauthorised Vaginal Examinations
Get PDFThis thesis considers the use of the civil tort of battery to address one form of obstetric violence: unauthorised vaginal examinations. The work critically engages with the benefits and limitations of applying tortious battery to this manifestation of obstetric violence, and determines the extent to which the action could address the wrongs and harms of UVEs
Experimental and Computational Studies of Oxide Ion Conductors
Get PDFThe work in this thesis focuses on the study of oxide ion dynamics with the aim to develop improved oxide ion conductors. As the main techniques used to achieve this were ab initio molecular dynamics (AIMD) and quasielastic neutron scattering (QENS), this combined approach is also the focus of the literature review in Chapter 1.
Chapter 2 introduces the methods used for synthesis, characterisation, and further study of the materials studied.
Chapter 3 investigates the effect of the dopant on the oxide ion dynamics in two doped -BiO oxide ion conductors: BiVO and BiPO. QENS allowed observation of nanosecond dynamics, corresponding to the diffusion of the oxide ions in the Bi-O sublattice via vacancy-hopping, and picosecond dynamics, corresponding to localised motion within the dopant sublattices. AIMD gave further insight into the different oxide ion dynamics in BiVO and BiPO, showing that the flexibility of the V coordination environment plays an important role, creating additional vacancies in the Bi-O sublattice, consistent with the superior conductivity of the vanadate.
Chapter 4 describes the systematic study of conductivity of the complex scheelite-type materials: Bi(BO)(B'O) (B = Fe, Ga, FeTi; B' = Mo) as well as Bi(BO)(B'O) (B = Sc, In; B' = Mo). Impedance measurements indicate that interstitial oxide ions are responsible for conductivity in these materials, and the conductivity of Bi(FeTiO)(MoO) was found to be 1.5 10 S cm at 800 C, which is comparable to the scheelite-type oxide ion conductor LaNbWO
Chapter 5 discusses the study of two hexagonal perovskites: BaNbMoO and BaNbMoO. Using variable temperature powder X-ray diffraction, the reversibility of the phase transition in BaNbMoO was demonstrated for the first time. QENS showed that oxide ion dynamics in both compounds are too slow to be observed on a nanosecond timescale. In BaNbMoO, AIMD revealed a continuous oxide ion migration pathway in the plane, and moreover showed an important out-of-plane contribution to the long-range diffusion. This allowed suggestion of a new doping strategy to further enhance oxide ion conductivity.
Chapter 6 discusses results obtained from the first AIMD simulations on a Dion-Jacobson phase oxide ion conductor, CsBiTiNbO, revealing an important contribution of the O2 site to the long-range diffusion. This suggests that oxide ion migration occurs predominantly via an O1-O2-O1 pathway, demonstrating the importance of rotationally flexible octahedra for high ionic conductivity in this new family of oxide ion conductors
Of Rurban and its Waters
Get PDFUsing a qualitative approach and a case study method, this thesis advances the conceptualisation of rurban and contributes to the understanding of corresponding rurban water governance. In the context of Haldwani, a small city in the Kumaon Himalaya of Uttarakhand State in India, it is argued that a rurban space may or may not be at the immediate periphery of the urban centre, and it may or may not become urban. In this thesis rurban is conceptualised through the flows of goods, services, and resources between rural and urban. It is seen as a construct that is process-based and not an entity that is socio-organisational; it is studied through processes that lead to its creation and not as a state of being, or a way of life; as rurbanisation and not as rurbanism. In studying rurbanisation, emphasis is laid on enhanced historical sensitivity towards the economic, socio-political, and demographic foundations of rural-urban changes.
In the dynamic context of rurban, a corresponding ever-evolving water governance is established. Institutional bricolage is used as a conceptual tool to unpack the water governance in rurban Haldwani.
Rurban water governance is imbued with the agency of the users and is characterised by ‘thick’ institutions made by piecing and layering of historical, contemporary, traditional, customary, and statutory practices, norms, rules, and codes of conduct. The research captures changes in everyday practices and logics surrounding water access and use, as well as the meanings locals ascribe to the shifting spatial contexts of rural-urban interaction.
This study paves the way for future studies on rurban resource governance, with a greater acknowledgement of the role and agency of rurban residents in making of the rurban space, and in (re)creation of institutional arrangements around resource use and access
The Reception of the Ruins of Palmyra in the Long Eighteenth Century: 1678-1820.
Get PDFRediscovered in the late seventeenth century by English explorers, it was not until the arrival of Robert Wood, James Dawkins and Giovanni Battista Borra that the ruins of Palmyra in Roman Syria were communicated more broadly to a Western audience. Wood’s Ruins of Palmyra (1753) - funded by plantation owner Dawkins’ wealth and driven by the architectural draftsman Borra’s plates - transformed Palmyra from a little known curiosity into a cultural sensation. This thesis uses the illustrated publication as a fulcrum to explore the ways in which images of the city’s major monuments permeated the architectural and visual culture of the period. From illusionary exhibits at Vauxhall Pleasure Gardens to miniature Plaster of Paris models, Palmyra was transformed into a diverse range of different media that captivated a widespread audience with the picturesque appeal of its desert ruins.
Designed as an investigation of Palmyra’s place in cultural and architectural history, the project is motivated by the visual archive of the site split between various collections across Europe and the United States. The objective is to excavate the legacy of Palmyra in the Western imagination and explore each source in its historical and cultural context. In so doing, the ruins’ significant role within the classical tradition can be outlined systematically for the first time as a rival to Rome and Athens. The reception of the ancient city altered from an interaction with its archaeological record to a preference for the pictorial quality of its exquisitely preserved ruins. Rather than an epitaph for a now mutilated site, this work offers new approaches for research into one of the most important and beautiful sites in the region
Characterisation of new genes involved in Arabidopsis vascular development
No full textThe vascular system of plants is composed of two main tissues: the xylem and phloem, which arise from meristematic cells positioned between them. Xylem is the woody tissue responsible for water transport, while the phloem transports photosynthates. PHLOEM INTERCALATED WITH XYLEM (PXY) is a receptor-like kinase, which in cooperation with its peptide ligand TRACHEARY DIFFERENTIATION INHIBITORY FACTOR (TDIF), controls the formation and maintenance of the vascular tissue. Despite the crucial importance of PXY-TDIF in controlling vascular development, the principles coordinating these elements remain unknown. TDIF is derived from CLE41, but the mechanism whereby CLE41 is cleaved into TDIF, TDIF secretion by phloem cells, and events in the cytoplasm following TDIF binding to PXY is unknown. Where some components of TDIF-PXY signalling have been described, interacting factors are not known. Consequently, knowledge of PXY signalling remains somewhat limited. To identify new components of TDIF-PXY signalling, a mutagenesis screen was performed in lines over-expressing TDIF. In this thesis, wa3 and wa10 were identified as suppressors of the TDIF over-expression phenotype, and were thus hypothesised to encode components of PXY signalling. The wa3 lesion was not identified, but wa10, characterised by a complete suppression for 35S::CLE41 was found to encode a WD40/transducing domain-containing protein, which we renamed PUCK. Further alleles were used to verify that mutations in PUCK could suppress CLE41 overexpression phenotypes. Genetic interactions with pxy, er and bp were also analysed
Factors shaping the population structure and historical abundance of pinnipeds and penguins
Get PDFThe idea that there is a causal chain between ecological pressures, demographic trends, and the distribution of genetic variation in a population underlies the use of genetic markers to model biogeographic history and conservation priorities. Ecological traits are increasingly being linked to genetic loci in studies of natural selection, but are often only gestured at in studies using neutral markers to study population structure and demographic history. In this thesis, I investigate the modern population structure of the South American sea lion (Otaria flavescens) using SNPs derived from reduced-representation genome sequencing (RADseq) and mitochondrial loci, finding no evidence for nuclear structure, but confirming the existence of matrilineal (mitochondrial) structure and suggesting that it may have developed relatively recently. I then show that the populations of O. flavescens and a sympatric and ecologically similar penguin species, Spheniscus magellanicus, expanded at different times in the mid-to-late Holocene, paralleling recent dietary shifts indicated by analysis of stable isotopes (δ15N and δ13C), possibly towards more benthic prey.
To help identify populations with especially similar demographic histories and try to understand what ecological factors explain their similarity, I developed a program called ‘align_stairwayplot.py’, which quantitatively compares demographic histories based on a metric combining the magnitude of, and level of model support for, their growth or decline trajectories at aligned time points. With the support of this tool, I found that populations of pinniped and penguin species shared common patterns in their demographic histories that allowed them to be clustered with reasonable accuracy, even with low sample sizes. Antarctic and sub-Antarctic penguins had highly similar demographic responses to the last glacial maximum (LGM), but that the response was weaker in the most ice-tolerant species, the emperor penguin. Globally distributed pinniped species fell into clusters based on the similarity of their demographic histories; their relationships were best explained by differences in latitude from among the factors considered, but conclusions were limited by lack of diet information and small sample sizes with respect to some factors
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