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Unveiling the True Colours of Red Quasars
No full textThe archetypal signature of an unobscured quasar, which constitute the majority of the optically-selected quasar population, is broad emission lines superimposed onto a luminous blue thermal continuum. Consequently, it was long believed that quasars are only blue in colour. However, the discovery of a small, but significant, subset of quasars with redder continuum emission over 20 years ago, has challenged the conventional view. In this thesis I have investigated the fundamental differences between red and blue quasars, using SDSS- and NuSTAR-selected quasar samples, where the latter quasars represent the less luminous end of the population. Consequently, we have found that the majority NuSTAR red quasars ascribe their redness to dominant host galaxy emission. On the other hand, we have shown that the luminous SDSS quasars are outshine their host galaxy. The evidence presented here for the SDSS-selected quasars supports dust-reddening as the key ingredient for the observed colours in the intermediate-radio, compact red quasars, with jet- and wind-driven outflows. This is consistent with the picture of red quasars being in a young, evolutionary phase, enshrouded by a cocoon of dust, with strong winds and compact or frustrated jets. Our ongoing investigations appear to be confirming this phenomenological picture, although the key studies to conclusively confirm or refute this view are still to come
Assessing the palaeoceanographic and glaciological changes from the LGM to present in the Baltic Sea Basin and Baffin Bay, a multi-geochemical approach
Get PDFThe application of multiple geochemical techniques provides a robust tool for analysis, especially in regard to the study of sediment cores affected by complicated provenance, oceanographic and glaciological dynamics over time.
A multi-geochemical approach utilising proxies such as osmium isotopes (187Os/188Os), biomarker, XRF, qXRD, REE, radiocarbon dating and sedimentological details was applied to sediment cores from Baffin Bay, the Baltic Sea and the Skagerrak. This approach was applied with the goal of further understanding the complicated ice sheet dynamics and palaeoceanographic changes since the Last Glacial Maximum around the core localities, and how these may have been influenced by changes in climate (e.g., the Younger Dryas), which has the potential to help provide context for future glaciological and oceanographical changes in response to climate shifts. The use of the 187Os/188Os system as a proxy for glaciological and changes in basin inflow/drainage was also further tested, being applied to cores in the Skagerrak and Baltic Sea for the first time.
Through using combinations of the geochemical techniques listed above, large scale changes in the Baltic Sea Basin’s history can be identified through the tracking of inflow and drainage events both inside and outside the basin. The first evidence in the central Skagerrak for the final drainage of the Baltic Ice Lake through south-central Sweden is found, and the transition of the freshwater Ancylus Lake into the brackish Littorina Sea stage are clearly depicted in the data from the central Baltic Sea. These techniques, however, are unable to differentiate the weak, short-lived marine incursions into the Baltic Basin during the Yoldia Sea stage from the varying influxes of freshwater due to melt of the Fennoscandian Ice Sheet. Further, in Baffin Bay, a radiogenic, felsic sediment source is recorded during the Baffin Bay Detrital Carbonate layers. The potential provenance of this is likely material transported by the Greenland Ice Sheet, although a Laurentide Ice Sheet source is not ruled out completely due to similar geologies between west Greenland and Baffin Island. Further, synchronous behaviour of ice sheets is recorded over BBDC1 coincident with the B lling-Aller d and Older Dryas, and asynchronous behaviour is recorded over BBDC0 coincident with the Younger Dryas showing a dynamic response from the ice sheets over both warmer and cooler climate periods
STAKEHOLDER ENGAGEMENT IN SUSTAINABILITY REPORTING IN INDONESIA
Get PDFThis research aims to understand the ways the preparers of sustainability reports in Indonesia embed stakeholder engagement in sustainability reporting. This research seeks to understand the perceived role of stakeholder engagement in sustainability reporting and examines whether the report preparers decouple their stakeholder engagement disclosures from the actual practices. The neo-institutional theory is used to illuminate the companies’ non-conformity responses to institutional influences.
This research utilises mixed methods by deploying questionnaires, sustainability reports and semi-structured interviews. The questionnaire survey was analysed using descriptive statistics. The interviews were conducted face-to-face and analysed using thematic analysis. Content analysis of stakeholder engagement disclosures was also undertaken on the 2007 to 2018 sustainability reports issued by the companies participating in the interviews.
The findings of this research reveal that the report preparers attempt to embed stakeholder engagement in the companies’ sustainability reporting in response to coercive, normative and mimetic influences. However, stakeholder engagement is loosely embedded as a result of contextualising the Global Reporting Initiative (GRI)’s conception of stakeholder engagement into Indonesia’s local contexts. Stakeholder engagement is perceived as having important roles in mandatory corporate social responsibility (CSR) programmes and materiality assessment to define the report content. External stakeholders are engaged more inclusively in the former whereas internal stakeholders take control of the latter.
It is not evident that the report preparers in Indonesia decouple stakeholder engagement disclosures from practices. However, the ways in which the companies practise their stakeholder engagement (means) deviate from the goals of stakeholder engagement suggested by the GRI’s principles for defining the report content (ends), known as the means-ends decoupling. The report preparers in Indonesia accept the GRI’s concept by meeting the suggested indicators, but unintentionally overlook the GRI’s principles that are required to be implemented as a new institution, rather than intentionally avoiding them.
The main contribution of this research to the literature is that it provides insights into the need to embed stakeholder engagement in sustainability reporting in an integral way, including by translating the GRI’s global conception into local context. This research also provides insights into the presumption that ‘companies report the practice’ of stakeholder engagement in sustainability reporting—as suggested by the GRI and the extant literature. Just because the companies report the practice (means) by making reference to the GRI, it does not necessarily follow that the companies have conformed to the goals of stakeholder engagement suggested by the GRI’s principles for defining the report content (ends). Taking into full consideration Indonesia’s politicoeconomic, sociocultural and legal contexts, which can be dissimilar to other local contexts, this research contributes to an understanding of decoupling, especially the means-ends decoupling, which tends to be unintentional in the companies’ non-acquiescent response to institutional influences. The decoupling indicates that the report preparers consider the GRI’s stakeholder engagement indicators as technical prescriptions leading to box-ticking activities, rather than being thoroughly understood and implemented as a new institution. Besides, this research offers a practical contribution in that the companies’ sustainability reporting consultants could shepherd their clients’ stakeholder engagement, guided by the GRI standards (previously called guidelines), to go beyond merely meeting the GRI indicators and producing ‘nice to read’ sustainability reports
Investigation of the Role of G3BP in Stress Granule Formation in Senescence
Get PDFSenescent cells accumulate with age and are defined as the cells that irreversibly lose their ability to proliferate. They are characterized by an enlarged flat cell phenotype, enlarged nucleus with persistent DNA damage foci, and an increase in senescence-associated β-galactosidase (SA-β-GAL) activity. The accumulation of senescent cells with ageing is associated with physiological decline and age-related diseases.
Cells experience stress and damage from internal or external sources which induce various responses ranging from recovery to cell death. They respond to stress by regulating RNA translation to allow the expression of proteins required for cell viability. During stress, untranslated mRNAs are re-directed from polysomes to cytoplasmic aggregates known as stress granules. The assembly of stress granules is promoted by RNA-binding proteins including G3BP which is the nucleating protein of stress granule assembly.
Mammalian cells have three G3BP proteins: G3BP1, G3BP2a and G3BP2b, encoded by 2 genes G3BP1 and 2. We investigated the formation of stress granules in proliferative, stress induced premature senescent (SIPS) and replicative senescent cells in primary human dermal fibroblast cells and U2OS cell lines. Senescence phenotype, stress granule formation, lipid droplet accumulation and differential proteome-wide expression were investigated in WT U2OS cells and in cells lacking G3BP1/2 as well as in cells that were reconstituted with a single form of G3BP
Openness to Competitors and Firm Innovation
Get PDFThis thesis aims to explore how firms can be open to competitors to innovate, mainly focusing on the determinants of openness to competitors, whether they should adopt knowledge-protection mechanisms and why they select different openness modes. Through a systematic review of the literature on the determinants of open innovation, I find that previous studies have provided insights in improving our understanding of the topic from a range of theoretical perspectives. Yet, extant research has shown diversities and discrepancies in the findings about how internal factors affect open innovation (i.e., “internal factors of open innovation success”). By identifying four dimensions of organization factors (i.e., resource investment, organizational structure, human capital and individual attitudes) and reviewing their effects on the implementation of open innovation, I generate a literature framework and discuss several directions for future research. Based on this, I focus on open innovation in competitive contexts, i.e., the openness to competitors, a field that has received relatively less attention. Then, I conduct two empirical studies using the data from the Spanish Community Innovation surveys. The first examines the determinants of openness to competitors from the absorptive capacity (ACAP) view. This study extends this view by adding a perspective of selective openness. The results suggest that after innovation failures, firms with more R&D investments are more likely to search for knowledge from competitors (competitor search), whereas they are less likely to build formal cooperation with them (competitor cooperation). Further analysis suggests that this risk-averse propensity is because of managers’ fear of the risks from competitors. The second empirical study examines whether or not a firm should adopt knowledge-protection mechanisms. I follow the ACAP view and conceptualize the process of absorbing competitors’ knowledge to innovate into two stages: potential and realized. I try to uncover the process through which R&D investment affects innovation performance by establishing the absorption of competitors’ knowledge as a mediator. My findings reveal that a firm’s R&D investment will increase its innovation performance, which can be achieved by absorbing knowledge from competitors. In addition, knowledge protection positively moderates the relationship between R&D investment and the absorption of competitors’ knowledge, while it negatively moderates the relationship between the absorption of competitors’ knowledge and innovation performance. Overall, this thesis contributes to the ACAP view and the literature on open innovation by exploring the determinants of openness to competitors, and by reconciling the debate on the paradox of openness and protection
On the Hasse Principle for Systems of Forms
Get PDFWe prove the Hasse principle for a smooth projective variety defined by a smooth system of two cubic polynomials in variables. The main tool here is the development of a version of Kloosterman refinement for a smooth system of equations defined over
A Commentary on Select Poems of Propertius 2.1-12
Get PDFThis thesis is a study of Propertius 2.1-12; I focus on specific elegies and contribute to the debate on whether the transmitted Book 2 of Propertius contains two originally separate books. I combine some literary critics’ poststructural approaches with some textual critics’ scepticism of particular aspects of the manuscript tradition to produce a text with accompanying commentaries and introductions to poems 2.1, 2.2, 2.3, 2.5, 2.6, 2.8, 2.9, 2.11 and 2.12, in addition to a main introduction. The notes and poem introductions explore how the text intersects with contemporary politics and philosophy, as well as contemporary and historical poetry and visual culture, to produce literature which is rich in potential meanings. As a result, the thesis contributes to our understanding of Propertius’ poems as pieces of art produced in the early 20s BCE. In accordance with modern commentary theory, the notes are interpretative, and the poem introductions counteract the atomisation inherent in lemmatisation.
As well as analysing the poems individually, I argue that poems 2.1-12 form a cycle that can be interpreted independently of 2.13-34, although, on current evidence, the form(s) in which these poems circulated in the ancient world is unclear. Following the resurgence in narratological interpretations of elegy, and inspired by the recent use of Hellenistic ethics to examine the corpus, I trace a unifying romantic narrative that reflects on the dangers of νόσοι, and the resulting ἀκράτεια, across 2.1-12
Surface Modification of PDMS Films through the Addition of Amphiphiles & Oils
Get PDFThere is a great deal of industrial interest in surfactant/polymer systems. In the case of fouling-release coatings, there is a desire to better understand the surface modification of coatings through the restructuring or migration of amphiphilic additives. This thesis is focussed on characterisation of model coatings consisting of a poly(dimethylsiloxane) network and one of a variety of nonionic surfactants to improve understanding of the factors affecting their accumulation at polymer interfaces, and the properties they impart on the coating. This is with the intention to feed into predictive models, capable of shifting industrial formulation away from current “brute force” methods.
Concentration profiling techniques did not reveal an excess of surfactant at the air-PDMS surface. However, adsorbed surfactant was detected at the water-PDMS interface, demonstrating a seemingly reversible accumulation of surfactant. Such accumulation yielded hydrophilised PDMS surfaces, driven by a reduction in the interfacial energy.
The phase behaviour also plays a role in the surface modification behaviour. Using members of the polyethylene glycol monododecyl ether (CE) surfactant series, a positive correlation between the measured hydrophilisation profile and the incompatibility in PDMS was found. However, such rapid hydrophilisation behaviour was not observed for the incompatible commercial fluorosurfactant Fluorolink E10-H, showing that the chemistry of the hydrophobic moiety is vital in dictating the surface behaviour. This difference between the fluorosurfactant and the oxyethylene alkyl ethers in PDMS may be due to the disintegration of surfactant self-assemblies in the latter systems. The importance of phase behaviour was further suggested by PDMS doped with tetraethylene glycol monododecyl ether (CE) being affected by the inclusion of alkane oils to the system, whereas Fluorolink E10-H-doped films showed no such behaviour.
This work has shown that it is possible to mimic many aspects of of the complex behaviour of surface-active materials in silicone resin, using simple, well-defined surfactants
The Temptation of Eve in Proba's Cento Vergilianus and Milton's Paradise Lost
Get PDFRe-narrations of biblical texts have a long and complex history. In this thesis I shall seek to answer two of the questions posed by the re-narration of biblical narratives. Firstly, I shall address the issue of why Christians have felt it necessary to re-write biblical narratives. I shall then turn my attention to the more interesting issue of how these texts could be, and indeed were, received as authoritative after the closing of the biblical canon. I shall begin by providing an overview of the scholarship so far. The second chapter will then address issues of terminology, genre, and methodology. Chapter three contains the first of my case studies, an analysis of the temptation of Eve in Proba's Cento Vergilianus. This is followed in chapter four by an investigation of the concepts of authorship and scriptural authority in late antiquity, the importance of an apostolic connection for a work's authority, the development of an authorial apostolic succession, and how this led to Proba's text being received as a form of subordinate scripture. Chapter five presents my second case study, Milton's Paradise Lost and is in turn followed by chapter six, which plots the history of literary interpretation as an inspired prophetic activity from its origins in the Jewish literature of the Second Temple period, through the Early Church's authorial apostolic succession, to the re-appropriation of prophetic identity by Protestant Reformers in the fifteenth and sixteenth centuries. Finally, I offer a brief conclusion in which I draw together the various means by which biblical epics have enabled authors to compose scriptural texts after the closing of the biblical canon in order to demonstrate the continuing existence of scripture beyond the Bible, and to call for a re-evaluation of the definition of 'scripture' as a result of these findings
Optimizing Weights And Biases in MLP Using Whale Optimization Algorithm
Get PDFArtificial Neural Networks are intelligent and non-parametric mathematical models inspired by the human nervous system. They have been widely studied and applied for classification, pattern recognition and forecasting problems. The main challenge of training an Artificial Neural network is its learning process, the nonlinear nature and the unknown best set of main controlling parameters (weights and biases). When the Artificial Neural Networks are trained using the conventional training algorithm, they get caught in the local optima stagnation and slow convergence speed; this makes the stochastic optimization algorithm a definitive alternative to alleviate the drawbacks. This thesis proposes an algorithm based on the recently proposed Whale Optimization Algorithm(WOA). The algorithm has proven to solve a wide range of optimization problems and outperform existing algorithms. The successful implementation of this algorithm motivated our attempts to benchmark its performance in training feed-forward neural networks. We have taken a set of 20 datasets with different difficulty levels and tested the proposed WOA-MLP based trainer. Further, the results are verified by comparing WOA-MLP with the back propagation algorithms and six evolutionary techniques. The results have proved that the proposed trainer can outperform the current algorithms on the majority of datasets in terms of local optima avoidance and convergence speed
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