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The atmospheric carbon dioxide concentrations (CO2) are projected to rise from 400 ppm to 1000 ppm by the end of 21st century. The increase in atmospheric CO2 has been absorbed by the ocean resulting in a process called ocean acidification. Concurrently, the increase of atmospheric CO2 also intensifies the greenhouse effect, resulting in an increase of ocean surface temperature. The progressive modification of ocean environment is expected to affect marine ecosystems via changes in species behaviour, physiology and survival that will determine population, interaction within the community, with implications for biodiversity-mediated ecosystem functioning. Therefore, studying the combined effects of both drivers is fundamental for our understanding of future ocean environments. This PhD thesis reveals the impacts of both acidification and warming on behavioural and physiological responses of estuarine intertidal key species (Cerastoderma edule and Scrobicularia plana) and community. The community response to stressors can be due to direct effects of climate change on individual species as well as indirect effects via alterations of trophic interactions. In summary, this PhD reveals the impacts of lowered pH and elevated temperature on estuarine intertidal sediments at different levels of biological organisation. The observed distinct sensitivity of marine intertidal species to these stressors highlights the importance of ecosystem-based approaches incorporating all interactions.

Public Private Partnerships (PPP) have come to be preferred by governments for infrastructure development over traditional procurement. PPP is seen as the answer to many shortcomings of traditional procurement. Despite the complex nature of a PPP procurement process, governments around the world are emphasising and promoting competition within the procurement process. Competition is recognised as a significant element in the abundance of academic literature. Competition in the procurement process leads to desirable results for the procuring authority, by achieving value for money, encouraging innovation and promoting efficiency. Nevertheless, there is evidence that competition is still lacking within the PPP procurement process, so the idea of obtaining efficiency from the private sector may not be fully realised. This thesis first examines the procurement process from the global practice, and the integration of competition within the complexity of PPP. It then focuses on analysing the less known Malaysian PPP procurement process and the competition organised within its procurement process. A case study was conducted on the Malaysian Public Private Partnership Unit, Unit Kerjasama Awam Swasta (UKAS), to investigate the manner of competition incorporated within PPP in Malaysia. UKAS is the central agency responsible for facilitating and coordinating PPP implementation in Malaysia. The case study was generated from a combination of thirteen semi-structured interviews and multiple document reviews to address the research objectives. Content analysis was adopted to examine the interview transcripts and documents. Nvivo was later used to manage the coding process. Based on the empirical findings, in its effort to make the country’s PPP programme a success, UKAS has been flexible in its implementation, with less emphasis on incorporating competition within the procurement process. UKAS, however, still manages to procure infrastructure using PPP for the reasons for adopting PPP. This result in inconsistencies in UKAS governance on procurement process. Where the findings illustrate that value for money can be achieved by other means, the researcher concludes that competition involves more than achieving value for money; it can also be used as a procedural barrier, hence achieving good governance.

Police and Crime Commissioners (PCCs) are hailed as one of the greatest constitutional reforms of the police in modern times and were elected in 2012 in a blaze of controversy. Whilst some claim these powerful actors can ensure policing is more responsive to local priorities, others claim that PCCs will undermine democratic police accountability by encouraging populism and inequalities, and become too close to their chief constables to ensure that they are more robustly held to account. This thesis investigates whether PCCs have improved local police accountability through a mixed-methods study of how police-initiated stops are governed in three PCC areas, using interviews, observations, and statistical and documentary analysis. As such, it is one of the first empirical studies to explore this new model of police governance, certainly in relation to the operation of police powers. Research suggests that police-initiated stops are a flash-point in relations with ethnic minority communities, are disproportionately used against them, and has reduced perceptions of police legitimacy. Despite this, their use has grown exponentially and, as this thesis argues, is exemplary of a democratic deficit in local police accountability whereby police officers have become more responsive to national government in exercising their powers rather than local priorities. Unexpectedly, stop and search became heavily politicised during the fieldwork, resulting in improved governance and dramatic reductions in their use. The findings suggest that this was due to national developments, thus indicating that although police powers are amenable to external influence, their governance remains highly centralised. However, chief officers remain powerful in determining whether any reforms are implemented locally. Despite potential controversies, PCCs have been able to influence various operational practices but appear too hesitant to risk this for 'minority issues' like police-initiated stops, thus undermining their own capacity to enhance local democratic police accountability.

In recent years there has been an increasing interest in analysis and identification of complex molecules for the medical diagnostics, pharmaceutical research and homeland security applications. If these molecules are present in high concentration, a technique known as Raman spectroscopy can be utilized. Unfortunately, only one in every 1012 photon incidence on molecule undergoes Raman scattering resulting in weak Raman absorption. An efficient technique to overcome this limitation is to utilize surface-enhanced Raman scattering (SERS) whereby molecules are placed on the surface of nanostructured metallic substrate which performs the function of transducting photons into and out of the molecules. SERS extends the scope of Raman scattering to detect molecules at low concentrations to few/single molecule level. Previously the ‘KlariteTM’ substrate consisting of an inverted array of square based pyramidal nanostructures patterned onto a Silicon substrate has been demonstrated to afford highly reproducible SERS signals with approximately 107 enhancement factor. In this report, the effect of geometrical parameters associated with the inverted pyramidal array on SERS effect for sensing applications was investigated. Geometrical parameters studied include pitch length, pit size, aspect ratio of the base of pyramid and fill factor. 3D computational modelling based on Rigorous Coupled Wave Analysis (RCWA) is used to bridge with theory. From these observations, the geometrical parameters of inverted pyramid nanostructures have been optimized for better sensing ability. A test chip is fabricated for the purpose of performing a matrix experiment, allowing deconvolution of geometrical variables: lattice pitch (1000nm-3000nm), pit size (500nm-2500nm), pit aspect ratio [width to length]. Fabrication steps include electron-beam lithography, anisotropic wet etching and metallization. Computational and experimental reflectometry systems were applied to enable the identification and analysis of a variety of dispersive features including propagating surface plasmons, localized surface plasmons and diffraction dispersion. From the study of inverted pyramid, plasmonic behaviors are observed: 1. the surface plasmon polariton depends strongly on polarization. 2. Highly dispersive features arising from simple surface diffraction effects appear insensitive to polarization state. 3. As the pit size gets bigger, the diffraction efficiency decreases but the wavelength/angular position remain the same. 4. Diffractive features are relatively sharp and clearly defined (narrow bandwidth), and are highly dependent on lattice pitch. Hence they move in wavelength and angle (e.g. highly dispersive) as pitch is varied. These features relate to the coupling of light into or out of the sensor chip. 5. Localized surface plasmons have characteristic of small wavelength shift over wide angular range (low dispersion), and are generally broader in bandwidth. Plasmon features can conclusively be identified over diffractive features by making comparisons between simulations ‘with’ and ‘without’ the top metal coating. In order to derive the optimal geometry for SERS sensor, a highly stable test molecule which is known to form a monolayer coating on gold is required. For this purpose benzenethiol was used as standard in this work. Devices were tested using a Renishaw Invia Raman system. The main wavelength of interest here is 785nm where this laser is readily available and compatible with the end user Raman system. Full details of the optical and Raman measurements are carried out on the silicon test platform. Results show that the averaged SERS enhancement factor was only slightly dependent upon lattice pitch, but was highly dependent on pit size and aspect ratio. Density of the pits plays a further role simply by increasing the number of pits/unit area and so provides extra increase in SERS signal. The experimental data shows this is not simply a surface area dependent effect, but the optimal SERS signal can be obtained by close packing as tightly as possible pits of the optimal size. Minimum spacing (between adjacent pits) of 250nm is found to give the highest SERS enhancement. The optimal aspect ratio was found to be 1:1.2 and the optimal pit size determined to be 1000nm. This new optimized design shows 10-fold improvement in sensitivity compared to current available benchmark Klarite. The study has also explored the possibility of replicating the optimized design to a cost effective and disposable polymer for the purpose of mass production. This was carried out using nanoimprint lithography. The replicated plastic sensor is comparable to the benchmark silicon Klarite. As a proof of principle, the qualitative performance in two demonstrator molecules such as ibuprofen and melamine has been carried out. The disposable plastic sensor was demonstrated for the possibility of dual sensing mechanisms such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS). The sensitivity of plastic sensor using SPR mechanism is 225.83nm/RIU on thiol molecule. The work has also been carried out for an alternative SERS sensor design by changing the sidewall profile to 90˚ angle from (100) silicon etched plane. Changing the sidewall profile makes impact on the plasmonic behaviour. The straight sidewalls are favourable to the localized plasmon mode. The structures with slope sidewalls are favourable to both localized and propagating plasmons inside the cavities. This work was conducted as part of the FP7 ‘’PHOTOSENSE’’ consortium project.

Construction organisations have often been criticised for resistance to change and for failing to adopt innovative approaches to improve future business performance. Thus, the aims of this research is to improve knowledge-sharing approaches in construction organisations in Malaysia for improved performance, and the development of a conceptual model to support the implementation and embedding of appropriate knowledge-sharing approaches. It is anticipated that this will aid the implementation of knowledge-sharing approaches within Malaysia construction organisations and ultimately contribute to an improvement in organisation performance. This research employed both quantitative and qualitative approaches. Using random sampling, 1000 questionnaires were distributed to managers of small, medium and large construction organisations in Malaysia. Of these, 384 were useful for data analyses, a 38% valid response rate. To complement the questionnaire survey, 49 semi-structured interviews were conducted with top, mid and junior level managers of these organisations. Content analysis was used to analyse the information obtained through these interviews, whilst descriptive and inferential statistics were used to analyse the questionnaire survey. The results suggest that internet technologies as the most used formal approaches to knowledge sharing, and face to face social interactions as the most used informal approaches to knowledge sharing that are presently employed in Malaysian construction organisations. There is no significant difference in formal and informal approaches to knowledge sharing employed across different sizes and different managerial level of Malaysian construction organisations. In particular developing a knowledge-sharing strategy and integrating this into the company’s goals and strategic approach was regarded as the most challenging aspect in setting up knowledge-sharing approaches. Choosing an appropriate method to assess the impact of knowledge-sharing initiatives on business performance have found as the main challenges in implementing knowledge-sharing approaches by the construction organisations. The research further revealed that providing a conducive workplace setting, and providing training for education, personal and team development for effective knowledge sharing as most ready to setup and implement knowledge-sharing approaches. Furthermore this research has also recognised that the construction organisations can benefit from knowledge-sharing approaches in different ways to different size of organisation. The findings also indicate that the three top contributions of knowledge-sharing approaches to organisation performance are: increases efficient operations and reduces costs, improves better decision-making, and improves project and services delivery to the market. There is also conclude that no one knowledge sharing approaches that is likely to lead to successful outcomes in all organisations, but there are certain issues worthy of consideration in developing knowledge-sharing initiatives that offers potential for success. The realisation of this success will, however, depend on a host of factors, including organisational culture, structure and human resource practices. The findings from the research were then used to develop a conceptual model for the successful implementation of knowledge sharing in organisations and validated using a validation questionnaire survey within a range of SMEs and large construction organisations. The model presents a holistic way of accounting the key factors that impact upon the successful implementation of knowledge sharing in construction organisations. Such knowledge is essential to the management of construction organisations for achieving meaningful improvement in their approach to foster knowledge sharing.

This thesis presents a feasibility study on the conversion of biomass-derived pyrolysis oils to hydrogen gas via the advanced steam reforming processes of chemical looping reforming (CLR) and sorption enhanced steam reforming (SESR). According to thermodynamic equilibrium, the optimum conditions of steam reforming of model pyrolysis oils compounds were around 600°C and molar steam to carbon ratio (S/C) of 3, to save raising excess steam in the process. Palm empty fruit bunches (PEFB) pyrolysis oil and pine pyrolysis oil were investigated as renewable feedstock for H2 production. The experiments were carried out in a down-flow packed bed micro reactor using commercial Ni catalyst at 1 atm. The SIC of 1.89 (moist fuel) was found to provide the best operating conditions for steam reforming of both pyrolysis oils. In the SESR experiments, dolomite was mixed in the reactor bed to capture C02 produced from the steam reforming of pyrolysis oils. High sorption enhancement effects were demonstrated in particular for pine oil. Short CLR experiments were performed tor both oils using the same Ni catalyst acting as oxygen transfer material. The oils were able to reduce the catalyst close to 90% despite high O-content, and undergo CLR. The feasibility of steam reforming of aqueous fraction of pyrolysis oils was performed with co-reforming of ethanol using two catalysts: 'A' with a NiO loading of 18 wt% on α-alumina, and 'B' with 25 wt% NiO on γ-alumina. The aqueous phase was derived from water phase separation of the pine oil at a 1: 10 oil :water mass ratio. Both catalysts demonstrated high fuel conversion and H2 yield for S/C ratios between 2.4 and 4.8. Chemical looping reforming performed at S/C of 3.66 resulted in almost 90% reduction of catalyst A and around 20% reduction of catalyst B whilst maintaining nearly complete fuel conversion.

The present study tried to find out the implementation status of National Action Plan (NAP) for Education for All (EFA) in Myanmar by reviewing the achievement of EFA core indicators (CI). This was done by reviewing the EFA reports of the two latest years available, in this instance, the NAP 2003 and the only available later report, the Mid-decade Assessment Report 2007. This was supplemented by findings from, review of records and registers of five schools, household survey of an urban and a rural area, interview of a National EFA Team member, Focus Group Discussion (FGD) with teachers and community members and Field observations made by the researcher. The selection of schools and areas for household survey were carried out by means of stratified random sampling. Purposive sampling was used in selecting participants for FGDs. It was found that out of the 18 CI, Myanmar was able to report achievement of the target in 10 even though some were of doubtful accuracy and reliability, could not achieve target in 4 and data was not available for the remaining 4. The data reported for Myanmar in the UNESCO Global Monitoring Reports were also used to check the achievements of CI. From these data Myanmar was found to be in the lower middle part of the worldwide spectrum of EFA achievement with the possibility of not achieving some indicators by the year 2015. An interview of a member of the EFA team and Focus Group Discussions with selected teachers, PTA and community elders were also conducted to identify the difficulties, constraints and limitations met in implementation and monitoring the EFA activities. A feasible set of recommendations were then made based upon the difficulties, constraints and limitations identified above, with the aim of fostering greater achievement in coming years.

This thesis describes the synthesis and analysis of organometallic complexes that feature oligo-phenylene ethynylene based ligands. Chapter 1 introduces the general topic of molecular electronics and provides a general overview of the interest in phenylene ethynylene systems as foundation architectures for molecular wires. The role of metal complexes in molecular electronics and the application of the cluster - surface analogy to the study of model systems is also described. Chapter 2 describes the synthesis of oligo-phenylene ethynylene pro-ligands of the general form Мe(_3)SіС≡СС(_6)H(_4)C≡СС(_6)H(_4) (1-5), in which R is either an electron donor (Me, OMe) or acceptor (СО(_2)Ме, NO(_2), CN). The compounds were synthesised either via Sonogashira Pd/Cu cross-coupling reactions or via the nucleophilic attack of benzoquinones by lithiated acetylide anions and subsequent reduction. The desilylation of these compounds afforded the terminal alkynes НС≡СС(_6)Н(_4)С≡СС(_6)Н(_4)R (6-10). Furthermore, the extended "three-ring" 1,4- bis(phenyl ethynylbenzene) derivatives Мe(_3)SіС≡СС(_6)Н(_4)С≡СС(_6)Н(_4) ≡C(_6)H(_4)С≡СSiMe(_3), 11 and Мe(_3)SіС≡СС(_6)Н(_4)С≡СС(ОМе)(_2)(Н)(_2)С≡С(_6)Н(_4)С≡CSiMe(_3), 13 and the terminal alkyne НС≡СС(_6)Н(_4)С≡СС(OMe)(_2)(H)(_2)C≡ C(_6)(h)(_4)C≡CH (14) have also been prepared. These compounds were fully spectroscopically characterised and in the case of 14 the molecular structure analysis is discussed. Chapter 3 discusses the synthesis of the gold(I) oligo-phenylene ethynylene complexes The complexes were prepared by treating the ligands precursors 1-5 with АuСl(Рl(_3)) (L = Ph or Су) in the presence of NaOMe to afford complexes Аu(С≡СС(_6)Н(_4)С≡СС(_6)Н(_4)R)PPh(_3) [R = Me (15), OMe (16), СО(_2)Me (17), NO(_2) (18) and CN (19) and Аu(С≡СС(_6)Н(_4)С≡СС(_6)Н(_4)R)PCy(_3) [R = Me (20), OMe (21) and NO(_2) (22)]. The "three-ring" complexes {Аu(РРh(_3))}2(μ-С≡СС(_6)H(_4)С≡СС(_6)Н(_4)С=С(_6)Н(_4)С≡С), 23 and {Аu(РРh(_3)}(_2)( μ-C≡CC(_6)H(_4)C≡CC(_6)(OMe)(_2)H(_2)C≡C(_6)H(_4)C≡C 24 were also prepared. These complexes were spectroscopically characterised and molecular structural analyses reveal intermolecular interactions between the phenylene ethynylene portion of the molecules in the solid state, but not aurophilic interactions. Chapter 4 examines the synthesis of half-sandwich Ru(L(_2))Cp' [L = РРh(_3), Cp' = Cp ; L(_2) = dppe, Cp' = Cp*) acetylide complexes derived from simple phenyl, tolan and oligo(phenylene ethynylene) based acetylenes. The electrochemical properties of these complexes have been explored, as have some of the molecular structural details. Chapter 5 describes the synthesis of some cluster complexes. The gold acetylide complexes Аu(С≡СС(_6)Н(_4)С≡СС(_6)Н(_4)R)(РРh(_3)) react readily with Ru(_3)(CO)(_10)(μ-dppm) to afford phenylene ethynylene derivatives Ru(_3)(μ-АuРРh(_3))(μ-С(_2)С(_6)Н(_4)С≡СС(_6)Н(_4)-R)(μ-dppm)(C0)(_7) (38-42) in which the conjugated organic moiety is "end-capped" by the cluster and an R group that is either electron donating or withdrawing (R = Me, OMe, СО(_2) Мe, NO(_2), CN). The clusters 38-42 are linked to the hydrido clusters Ru(_3)(μ-Н)(μ-С(_2)С(_6)Н(_4)С≡СС(_6)Н(_4)R)(СО)(_7) (36 and 37) through the well-known isolobal relationship between H and Аu(РR(_3)). In addition, the bis-cluster {Ru(_3)(μ-dppm)(CO)(_7)}(_2){(μ-ΑuΡΡh(_3))}(_2)(μ-C(_2)C(_6)H(_4)C≡CC(_6)H(_4)C≡CC(_6)H(_4)C(_2)) (43) has also been prepared. All the clusters reported in this chapter were crystallographically determined. Structural, spectroscopic, photophysical and electrochemical studies were conducted and have revealed little electronic interaction between the remote substituent and the organometallic end-caps. Chapter 6 explores the novel, preparative scale stoichiometric transmetallation reactions involving the simple Аu(С≡СR)(РРh(_3)) (R = Ph or С(_6)Н(_4)Мe) complexes. These gold(I) complexes have been treated with several inorganic and organometallic compounds MXL(_n) [M = metal, L(_n) = supporting ligands, X = halide], to afforded the corresponding metal-acetylide complexes M(C≡CR)L(_n), with representative examples featuring metals from Groups 8-11. The acetylide products were fully characterised by usual spectroscopic methods including the molecular structural analysis. Chapter 7 concludes the general summary of the thesis and discusses briefly the findings achieved in each chapter and the vital role of oligo-phenyelene ethynylenes ligands in the construction of numerous organometallic complexes which show interesting and promising properties for the molecular wires development. In addition, further future work is also proposed on other systems that feature this ligands.

Quality of life (QOL) is an extremely important concept in the promotion of appropriate and successful health care programmes. However, there is a need for conceptual clarity to unravel the complexities of terminology in different medical conditions and the underlying factors that have a direct influence on the quality of life for people with coronary heart disease. The primary objective of this thesis is to propose a theoretical model which specifies the domains of QOL and the interrelationships among these domains. The objectives of the study are four-fold: (1) To examine whether a cardiac rehabilitation programme has a beneficial effect on cardiac heart disease patients; (2) To evaluate the primary components of generic health-related quality of life assessment tools for people with coronary heart disease; (3) To identify the main factors governing disease-specific health-related quality of life assessment tools amongst patients with coronary heart disease; (4) To examine a variety of conceptual models of QOL and to determine their relevance to cardiac patients. First, in order to provide conceptual clarity, a comprehensive review of QOL measures was undertaken. Second, data was collected on a cardiac rehabilitation programme in a county hospital using Short Form-36 (SF-36) and Quality of Life for Myocardial Infarction (QLMI) instruments. This data was analysed using a number of techniques including (l)meta-analysis; (2)discriminant analysis; (3)factor analysis and (4)structural equation modelling. Analysing the data in this way enabled the development and clarification of the specific domains of the quality of life model. Meta-analysis involved pooling the results of several studies, these were then analysed to provide a systematic, quantitative review of the data. The results found that the related studies did not have consistent outcomes to support the positive effects of a cardiac exercise rehabilitation programme on quality of life in coronary patients. Findings from the SF-36 indicate that older people with coronary heart disease gain more pain relief than their younger counterparts. After a cardiac exercise rehabilitation progranune, statistically significant improvements occurred in physical function, social function, role limitation/physical, energy/vitality, body pain, and change in health-related dimensions of quality of life. The first-order five domains model includes the symptom domain, the restriction domain, the confidence domain, the self-esteem domain and the emotion domain. This model represents an appropriate model of quality of life for people with coronary heart disease compared to the three-domain model and the four-domain model. In terms of the second-order QOL model, the five-domain model also has an adequate fit to the data. According to the result of structural equation modelling, three models, including the null model, the alternative model I and the alternative model n, did not fit the data perfectly. However, the construct of full latent variable model gradually increased the fit statistics from the null model to the alternative model I and from the null model to alternative model n. Therefore, it can be concluded that the paths and indicators of the three models need to be further adjusted in order to provide a more appropriate model. Nevertheless, this is a first trial to examine a full model of quality of life for people with coronary heart disease using the structural equation analyses. As such, this study provides a new approach to examining the difference between empirical studies and theoretical approaches.

The phenomena of seabed bathymetric changes in Dundee harbour, eastern Scotland have been investigated, by use of archive bathymetric data. The bathymetric data were available from the Dundee Port Authority, from its past annual harbour maintenance programmes during the period of 1989 to 1993. Archive bathymetric data are seen as under-utilised, after being used for their intended purposes. A methodology was therefore developed to use sequential bathymetric data to estimate the deposition and erosion of sediment over a period of time. This is in the form of a systematic procedure of processing for comparison of data from different dates. The comparison or differencing of bathymetric data in their original form cannot be directly applied. This would require each data point to be located at spatially common positions (i.e. grid points) and could be achieved only through interpolation. A procedure known as 'gridding' is instead used to prepare depths at the spatially fixed points or nodes. Six different methods of interpolation have been examined and trial computations using a common data subset for each individual method conducted. The results of the interpolation were often substantially different from one method to another. A technique known as the Blending Interpolation Technique is proposed to overcome the uncertainty in depth interpolation. Computer programs were specifically written for this study and for the visualisation of the phenomena of deposition and erosion, use was made of the available UNIRAS software package. The methodology and procedures of this study are not only applicable for an estuarine harbour environment, but are also equally applicable to any areas such as large reservoirs, lakes or coastal ports and harbours, that are continuously affected by the phenomena of sedimentation and erosion, where their estimation and quantification are of critical importance. This study, however, has demonstrated the usefulness of the Blending Interpolation Technique which is seen as a future tool to detect, monitor and quantify seabed changes, in particular where bathymetric data of the same area are available from different dates. It also serves to prolong the usefulness of archive bathymetric data kept for an area.

A seismic stratigraphic study of the regional lines for the offshore Sarawak area was undertaken with the aim of understanding the tectonics and sedimentation history of the hydrocarbon prolific Sarawak Basin. The aim here is to develop a workable stratigraphic scheme, a model of the sedimentation history of the basin, a model for Tertiary tectonics, and an analysis of the subsidence history of the basin. Six unconformities have been identified within the Tertiary sedimentary succession, based on seismic reflection and well data. Some unconformities coincide with eustatic sea-level falls; others are probably tectonic in origin. An alternative stratigraphic scheme for the Sarawak Basin was developed by subdividing the whole Tertiary succession into seven sequences. Palaeoenvironment maps of the basin document the interaction of tectonics and sedimentation commencing in late Oligocene times. Deposition started with a NW-SE coastline and a broad coastal plain, almost perpendicular to the present-day coastline (NE-SW) developed during late Miocene times. The maps illustrate the likely distribution of Sarawak Basin source and reservoir rocks which will help in effective planning for future exploration in the area. The Sarawak Basin formed as a result of NW-SE trending right lateral fault movement during late Oligocene to Pliocene times. This dextral movement was responsible for creating the NW-SE coastline and divided the offshore Sarawak area into two sub-basins. Deposition and preservation of coastal plain and shallow-marine sediments continued in the eastern area while the western area remained as a 'high' until late Miocene times and subsided during late Early to Middle Miocene. The dextral strike-slip movement which controlled the evolution of the Sarawak Basin is sub-parallel to a number of lineaments elsewhere in Sarawak. The timing of movement suggests a progressive younging in an eastward direction. Basin modelling suggests that the Sarawak Basin was characterised by rapid subsidence in the early stage of basin formation with a high stretching factor and episodic movements. This suggests that the basin did not form as a foreland basin nor as a typical rift basin, but indicates a strike-slip origin. Supplementary evidence for this is provided by the findings of the regional seismic stratigraphic study, which suggests that the whole onshore area of Sarawak and northern Borneo was subjected to strike-slip tectonism during Tertiary times. The driving force may have been initiated by the lateral movement between the Sundaland and South China Continental blocks, probably due to collision between Indian and Asian plates during the Middle Tertiary, continuing with the opening of the South China Sea during the Oligocene. The end result of tectonism in the region, however, is believed to be the combination of strike-slip movements and the counter-clockwise rotation of Borneo during the Oligo-Miocene. The superiority of the proposed strike-slip tectonic model over the present subduction model is the capability to explain most of the geological phenomena, including the absence of evidence for any subduction taking place in the area. The findings of this study should contribute towards a better understanding of the tectonics of the area which will be able to provide information on the development of structural traps for hydrocarbon plays that are believed to have formed by strike-slip tectonism.

Abd al-Qadir al-Jilani, a Muslim scholar who lived in Baghdad during the eleventh and twelfth centuries, was active in da'wah during his lifetime. Baghdad at the time was the capital of the Abbasid caliphate and the centre of the Muslim world. This thesis is an attempt to analyse al-Jilani's contributions to the methodological studies of Islamic da'wah. He is commonly known as a great sufi and the founder of the Qadiri Order. However, in this study I would like to highlight other dimensons of al-Jilani's expertise, namely those in the field of Islamic da'wah. Al-Jilani's methodology in da'wah can be taken largely from his books al-Fath a1-Rabbani and al-Ghunyah. After examining the contents of these books, besides other sources which ware written by historians and biographers, his methodology in da'wah can be summarised as follows: da'wah by goodly counsel, education, fatawa (legal decisions or interpretations), exemplary conduct and providing services and aids. In his capacity as principal of his school in Baghdad, al-Jilani was responsible for the spread of Islam among the people. His preaching instilled "faith in dead hearts" whilst simultaneously initiated productivity and energy in the people. As a sufi al-Jilani introduced a method of spiritual education for his disciples and made regulations for them to follow and practise in his book, al-Ghunyah. Al-Jilani frequently delivered fatawa and he often gave religious opinions as guidance, in addition to being a prolific writer. Al-Jilani was therefore, an outstanding figure in the field of da'wah in his time. His powerful personality and broad knowledge coupled with his spiritual strength helped him to spread Islam worldwide. The combination of sufism and shari'ah in his works showed his general spirit of reform in the field of da'wah. The connections between sufism, reform and da'wah are thus examined and discussed for their importance in Islam.

A 40 cc Ge(Li) detector has been used to study the gamma rays emitted in the decay of Cobalt-60, Areenic-74 and Neodymium-147. A system for measuring directional correlations has been constructed with a fast-slow electronics arrangement utilising the Ge(Li) detector and a NaI(Tl) scintillation counter, and the directional correlations of gamma-gamma cascades in Germanium-74 and Promethium-147 have been studied.

Coffee production in Vietnam has increased almost 100-fold within the past three decades, positioning it to become the second-largest coffee exporter in the world after Brazil. The U.S. is a top market for Vietnamese coffee. In this study, we estimate a conditional demand system of expenditure share equations for coffee from Vietnam, Brazil, Colombia, and an aggregate of seven other countries in the U.S. coffee market using the Linear Approximation Almost Ideal Demand System (LA/AIDS) and based on monthly time-series data from 2000 to 2020 with a total of 252 observations. Compensated and uncompensated own-price, cross-price, and expenditure elasticities were statistically significant at p < 0.001. Vietnamese coffee was found to be inelastic. The results suggest that increasing Vietnamese coffee prices could increase its revenue, while Brazilian and Colombian coffee exporters should be more careful in raising their coffee prices.

Internal combustion engines (ICEs) continue to be a major contributor to environmental air pollution. Emissions from ICEs play a big role in climate change and cause significant human and environmental problems due to both regulated and non-regulated tailpipe emissions. This has prompted the United States Environmental Protection Agency (EPA) to raise the emissions standards for ICEs causing engine manufactures to develop engines more efficient in reducing emissions. These EPA regulations have led some to transition from standard fossil fuels (gasoline and diesel) to alternative fuels and to raise the standard of emissions control technologies. The alternative fuels in this study include ethanol blend gasoline and compressed natural gas (CNG). Emissions technology of interest will include selective reduction catalyst (SCR), diesel oxidation catalyst (DOC), diesel particulate filter (DPF), and three-way catalyst (TWC). With the increasing fleet of vehicles on the road, some non-regulated emissions have become emissions of relevance as some are precursors in the formation of harmful secondary particulate matter (PM). This study investigates regulated emissions from CNG and diesel street sweepers in the South Coast Basin region of California. Second, this study investigates two non-regulated emissions, ammonia (NH3) and nitrous oxide (N2O), in the present fleet of light-duty passenger vehicles (2016-2021) fueled with 10% ethanol blend gasoline (E10) and 15% ethanol blend gasoline (E15).

Inherited retinal degenerations affect millions of people worldwide, with few or no treatment options. The most prevalent form of progressive retinal degeneration is retinitis pigmentosa, a heterogenous disease affecting over one million people around the world. Over 70 genes have been shown to cause retinitis pigmentosa, mainly affecting rod photoreceptors. As genetic mechanisms are identified, gene therapy becomes a promising potential treatment through gene replacement. However, gene replacement therapy is not a viable option for several of these diseases, where autosomal dominant forms such as the P23H mutation of rhodopsin require gene silencing instead of replacement. Since retinitis pigmentosa patients mostly present mutations in genes necessary for correct function of rod photoreceptors, leading to subsequent loss of cones, it is possible to target cone survival and provide a wide-ranging solution. Rod-derived cone viability factor (RdCVF) has been shown to be essential for cone survival, as it is produced and secreted by rods and promotes glucose uptake by cones. Chapter 2 of this dissertation examines the delivery of RdCVF through an AAV viral vector to a transgenic pig model of autosomal dominant P23H retinitis pigmentosa. Previous studies have shown cone rescue through delivery of RdCVF in mice, and here we explore therapeutic delivery to a large animal model that more closely resembles humans. In this study we report that RdCVF rescue is dose-dependent, as well as dependent on retinal regions reached by AAV. While electroretinogram results are not conclusive, immunohistochemistry indicates improvements in cone morphology and even rod retention in the retinal tissue. For more common recessive retinal diseases, such as the wide variety involving neuronal ceroid lipofuscinoses (NCL), gene replacement therapy is desirable. Of the 14 genes responsible for NCL, all but one are recessive, causing lysosomal dysfunction that leads to cerebellar atrophy, seizures, and in most cases retinopathies and vision loss. As gene therapies are developed targeting the brain, it is also advantageous to target the retina, as patients would require both forms of treatment. In chapter 3 of this dissertation, a gene therapy for CLN11, caused by mutations to the progranulin gene, is developed. Progranulin is a protein secreted mainly by microglia in the brain and retina, and is then endocytosed by neurons, thus regulating their lysosomal function. Absence of progranulin causes cerebellar atrophy, seizures, ataxia, dementia and vision loss. In this study we characterize the retinal degeneration in a progranulin knockout mouse model of CLN11 and study the effects of gene replacement at different time points. While mice that receive AAV vectors carrying the progranulin gene at post-natal day 3 or 4 show reduction in retina thinning, mice intravitreously injected at months 1 and 6 show no improvement, and mice injected at 12 months of age show increased retinal thinning in comparison to their controls. Thus, delivery of progranulin proves to be time sensitive, requiring early delivery. This is potentially due to its secretion, although further studies are required to elucidate this phenomenon.

Viewpoints on different assessment systems used throughout the world are diverse and continually evolving, shaped by shifts in the forms of assessment: from exam-dominated systems to school-based assessment; from norm-referenced to criterion-referenced assessment; and from assessment of learning (AoL) to assessment for learning (AfL). This has resulted in a shift in the role of teachers and in the conceptualisation of their requisite assessment knowledge and skills, commonly known as their assessment literacy. However, very little attention has been paid to pre-service teacher (PST) AfL literacy despite research evidence showing that initial teacher education is problematic and PST AfL literacy remains relatively low. Drawing on a socio-cultural approach which views the relationship between theory and practice as praxis, this study investigated in what ways pre-service teacher education can be adapted to help develop AfL literacy among PSTs. Using design-based research (DBR) methodology, a needs-based professional development (PD) program for PST AfL literacy was developed at a leading university in Myanmar. A total of 335 PSTs, with 30 PSTs in the intervention group and 305 PSTs in the cohort group, were asked to self-assess their AfL literacy before and after the program through a survey based on Nguyen (2016). An analysis of the pre- and post-survey showed a significant intervention effect of the PD on PSTs’ overall AfL literacy. In addition, semi-structured individual interviews were undertaken with the intervention group before and after their two-week teaching practicum in schools. This data was analysed together with data collected during their practicum, including lesson plans, observation checklists and audiotapes of lessons. This data demonstrated the ways in which the PSTs in the intervention group were able to apply their knowledge and skills learnt in the PD program in actual teaching practice. The findings revealed that there was an interaction of influences among the PSTs’ beliefs, understandings and confidence in AfL literacy, their efforts to apply AfL strategies in their practicum, and their supervising teachers and students’ responses to these. The overall findings of the study demonstrate the value of DBR as a pedagogical approach to professional development in pre-service teacher education, and the important contribution of explicit teaching of AfL literacy to preservice teachers as one way to change the assessment culture in schools to focus more on improving student learning.

This dissertation explores the manipulation of charges in a 2-D self-assembled organic molecular cluster and the manipulation of a molecular machine, a nanocar, using a low temperature ultrahigh vacuum scanning tunneling microscopy on a metal substrate.A donor-acceptor type organic charge transfer salt, α-(BEDT-TTF)2-I3 or α-ET2-I3 (BEDT-TTF=ET=Bis(ethylenedithio)tetrathiafulvalene), is thermally deposited onto Ag(111) substrate for different coverages. The scanning tunneling microscope (STM) investigation reveals different molecular assemblies in the first layer clusters, from partially ordered to ordered arrangements, at the sub-monolayer regime. At slightly higher coverages, the formation of charge density wave (CDW) is observed for the first time at both 5K and 80K substrate temperatures on 2 and 3 monolayer thick molecular islands. The nature of CDW is studied using scanning tunneling spectroscopy (STS) and density functional theory calculations. Furthermore, the observed CDW in the molecular islands is manipulated by using inelastic electron tunneling (IET) and the electric field supplied from the scanning tunneling microscope (STM) tip. The CDW patterns can be destroyed above 1.6V bias however, the same CDW pattern can be reinstated when the STM images are acquired by reducing the bias voltage. Using IET manipulation, the bi-stable deformation nature of CDW modulation is explored, and switching between two CDW states as a function of electric field and current densities are statistically analyzed.The molecular nanomachine, the nanocar, formed by using supermolecular [5]pseudorotaxane as an H-shaped frame and four Cucurbit[7]uril (CB[7]) as wheels, is thermally deposited on Au(111) substrate. The STM tip is used to extract a wheel from a nanocar to confirm its integrity upon deposition onto the surface, and to investigate the structure of the wheel. The chassis of the nanocar includes positive charges, which are used for the controlled driving of the nanocar using the STM tip induced electric field manipulation. The threshold electric field required to manipulate is also determined and found to be ~800mV.

Local people in the Central Dry Zone (CDZ) of Myanmar have been facing climatic variability for several decades. They are among the first communities to observe climate and environmental changes first-hand, and are applying traditional knowledge and skills in order to adapt to these changes. We used participatory action research in which a series of group discussions and debates were conducted in community workshops at the village level. Using this input, we analysed the perceptions of the local people about climate variability, impacts, and adaptation practices. The majority of the local people perceived climate change patterns in the CDZ with the increase of temperature and erratic rainfall patterns perceived as the most critical changes. The majority of the people also perceived that the impacts of climate change have already been affecting agriculture and its related sectors, including land and water resources and their livelihood strategies. Most of the local people also perceived that migration of young people away from the communities has gradually increased due to the consequences of climate change impacts. Farmers have already been attempting to cope with those climate change impacts by using locally relevant adaptation measures such as mixed and multiple cropping systems, changing to drought-resistant plant varieties, and using soil conservation measures to cope with water scarcity. In addition, most of the local people perceived that getting information from traditional weather prediction was helpful to cope with drought and erratic rainfall patterns. However, the results suggest the adaptive capacity of the local people in responding to the impacts of climate change can be improved. In this regard, effective adaptation planning relies on the best available knowledge base, and the urgent need to respond to the pressures of climate change has put a premium on the generation, interpretation and use of information to improve adaptive capacity, including improved access to scaling up the traditional best practices of local people.

BACKGROUND: Crohn's disease (CD) is an inflammatory bowel disease (IBD) and has been associated with Mycobacterium avium subspecies paratuberculosis (MAP). MAP has been detected in stool, tissue and blood samples from patients with CD. Gamma interferon (γ-IFN) is an inflammatory cytokine that plays a crucial role in killing intracellular pathogens like MAP, and its receptor (IFNGR1) mutations cause immunodeficiency and severe disseminated mycobacterial infections. The role of MAP in association with IFNGR1 mutation in CD patients have not been investigated. METHODS: In this study, we investigated blood samples of 79 human subjects for MAP infection in association with IFNGR1 gene dysfunction. Samples were divided into 22 CD, 6 Ulcerative colitis (UC), 32 normal healthy and 19 non-inflammatory bowel disease (NIBD). Five variants of IFNGR1 single nucleotide polymorphisms (SNP) were investigated using Taqman Genotyping assay, then IFNGR1 expression measured by RT-PCR and serum IFNGR1 and γ-IFN levels were measured using ELISA. MAP infection was detected using nested PCR. RESULTS: Among 28 IBD patients, 4/6 (66.67%) of UC and 18/22 (81.82%) of CD are tested positive for at least one SNP homozygous minor form compared to 21.88% and 47.37%% in 32 healthy and 19 NIBD (P < 0.05). IFNGR1 gene expression was downregulated 1.4-fold in IBD patients (P =0.07) and 1.7-fold downregulated in MAP positive IBD patients compared to MAP negative IBD patients (P=0.06). Serum IFNGR1 protein levels were downregulated 1.53-fold in IBD patients compared to normal, and 1.4-fold downregulated in MAP positive IBD patients compared to MAP negative IBD patients. MAP infection is more common in rs2234711 SNP positive patients (5/7 =71.42%) (P < 0.05). Serum γ-IFN levels were not elevated in both groups. CONCLUSION: IFNGR1 SNP's, MAP infection and IFNGR1 downregulation were found in higher incidence in IBD, suggesting role of IFNGR1 in susceptibility of MAP infection in IBD patients.

Human cytomegalovirus (CMV) is the major infectious cause of congenital malformation in developed countries. CMV is transmitted from the pregnant mother to the fetus via the placenta, with placental trophoblasts being recognised as an important reservoir for the virus. CMV infection can also lead to changes in cytokine profiles, and inflammation of the placenta, with implications for pathogenesis of fetal disease. This study investigated the importance of viral pentameric complex of gH/gL/pUL128-pUL131A, and cellular platelet-derived growth factor receptor-α (PDGFRα) for CMV infection in placental trophoblasts. The relationship between CMV infection and cellular changes, as well as the immunomodulatory properties of CMV-encoded proteins were also examined. Investigation in trophoblast cell lines has revealed CMV was able to enter these cells via different pathways, involving at least the viral pentameric complex of gH/gL/pUL128-pUL131A and cellular PDGFRα receptor. Infection with four CMV strains (Merlin, TB40E, Towne, AD169), and mutant Merlin strains with deletion of individual open reading frames UL128, UL130, or UL131A, showed the viral pentameric complex was essential for infection of HTR-8/SVneo trophoblasts, but non-essential for infection of SGHPL-4 trophoblasts. Analysis of the cell surface receptor PDGFRα, a receptor for CMV entry into human fibroblasts and glioma cells, showed differential expression of the receptor in these trophoblasts. Neutralisation, and transient expression of PDGFRα in respective SGHPL-4 and HTR-8/SVneo trophoblasts, demonstrated PDGFRα provides a different entry pathway for CMV that is independent of the viral gH/gL/pUL128-pUL131A pentameric complex. CMV infection has been shown to induce many host genes, many of which encode for inflammatory proteins. Analysis of the pro-inflammatory cytokines (CCL2 and TNF-α) in CMV-infected fibroblasts showed significant alteration in intracellular and extracellular CCL2 levels during the course of infection. Comparison between live and UV-irradiated viral infections showed changes in CCL2 levels were a direct response to active CMV replication. There were no significant changes in TNF-α expression during a parallel time course of CMV infection. In transient transfection assays, overexpression of CMV tegument protein pp71 resulted in intracellular and extracellular upregulation of CCL2, which was mediated through transcriptional upregulation. Therefore, CMV-induced upregulation of CCL2 during early stages of infection is mediated, at least in part, by stimulation of viral pp71. Infection with CMV clinical strain Merlin resulted in a pro-inflammatory shift in cytokine profiles in trophoblast cultures, suggesting infected trophoblasts are key contributors for production of inflammatory mediators within the placental tissue. Using the siRNA-targeted inhibition of UL111A and ORF94 gene transcripts, the immunomodulatory properties of these gene products were also investigated in infected SGHPL-4 trophoblasts. Notably, the viral replication in trophoblasts was reduced upon inhibition of UL111A and ORF94 transcripts, although this effect was not observed in MRC-5 fibroblasts. There was no evidence for modulation of cytokine levels in infected trophoblast cultures by UL111A and ORF94 gene products, suggesting these genes may not be critical for immune evasion during CMV infection of the placenta. Despite advances in the diagnosis of maternal and fetal CMV infection, an effective therapy remains unavailable to prevent materno-fetal transmission of the virus, and the adverse pregnancy outcomes associated with infection. This study demonstrated that CMV uses multiple entry pathways, involving at least the viral pentameric complex of gH/gL/pUL128-pUL131A and PDGFRα receptor for entry into placental trophoblasts. This added to the existing knowledge of gB-mediated entry into trophoblast progenitor cells, possibly via co-expressed epidermal growth factor receptor and integrin receptors. These findings indicate therapeutic treatment targeting multiple entry pathways is required for efficient blocking of CMV infection in placental trophoblasts (and possibly other placental cell types), thereby preventing the transmission of virus across the placenta during pregnancy. The induction of CCL2 by infected fibroblasts and trophoblasts indicates immune cells are potentially attracted to the sites of infection and mediates the inflammatory process within the placenta. On the other hand, uninfected immune cells attracted to the site of CMV infection may become infected, and facilitate dissemination of the virus. In addition to the induction of CCL2, CMV-infected placental trophoblasts can also elicit a strong inflammatory response through induction of many pro-inflammatory cytokines. The Th1 predominant pro-inflammatory shift in cytokine profiles has important consequences for placental development, normal placental function, materno-fetal virus transmission, fetal growth and fetal viability. Further investigations are required for improved understanding of virus-cell interactions, particularly, CMV entry and infection in different primary trophoblast cell types, as well as the immunomodulatory properties of other CMV gene products in these trophoblasts.

The evolution of the Ag(111) surface state near the zero, one and two dimensional defects is explored using a ultra-high vacuum low temperature scanning tunneling microscopy. A carbon monoxide CO molecule adsorbed on Ag(111) surface, an Ag(111) step and a BETS-GaCl4 cluster and layer on Ag(111) are used as zero, one and two dimensional defects, respectively. The dI/dV spectra are acquired as a function of distance from the defects in atomic scale and analyze the behaviors of the surface state intensities and on-set energies. In all cases, the surface state intensity decreases near the defects. However the surface state on-set energy shows different behaviors. In this thesis, a simple model based on the interference of plane waves due to reflection is proposed and simulated to explain the oscillations in dI/dV spectra appeared above the surface state onset energy. The results show that unlike Ag(111) step and BETS-GaCl4 layer, the reflection of electrons at the CO molecule and the two dimensional molecular cluster are very weak. These results open similar studies on other interesting system such as superconductor-metal boundary at the ultimate atomic limit.

Even though chlorophosphazene chemistry has been around since the 1800s, it was not until the 1950s when Allcock successfully synthesized the soluble chlorophosphazene polymer that the door to functionalized polyphosphazenes was opened. At present, polyphosphazenes constitute the largest group of inorganic backbone polymers, with their potential applications ranging from elastomers to biomaterials. Most functionalized polyphosphazenes are derived from polychlorophosphazenes. The problems surrounding the synthesis and storage of polychlorophosphazenes hinder the commercial development of functionalized polyphosphazenes. In the quest for a cost-effective synthetic route and for storage solutions, our group focuses on the fundamental chlorophosphazene chemistry. This dissertation discusses our endeavors to understand fundamental chlorophosphazene chemistry, the majority of the work being on the chemistry of [PCl2N]3. The dissertation is divided into six chapters; Introduction, Mechanistic Studies of the Fluxional Behavior of Group 13 Lewis Acid Adducts of [PCl2N]3, Group 13 Super Acid Adducts of [PCl2N]3, Crown ether complexes of HPCl6, Reactions of Group 15 Superacids with Chlorophosphazenes and Conclusion. Chapter I, the introduction, provides the overview of the previous studies of the acid-base chemistry of chlorophosphazenes. Chapter II describes a mechanistic study of the fluxional behavior of the Group 13 Lewis acid adducts of [PCl2N]3 and evaluates the likelihood that these adducts are directly involved as intermediates in the ROP process. The synthesis and characterization of Group 13 superacid adducts of [PCl2N]3 are discussed in Chapter III. The fragile acid HPCl6, which can potentially play an important role in chlorophosphazene chemistry, was isolated as complexes of crown ethers. Chapter IV describes the synthesis and characterization of these complexes. The reactivity of Group 15 acids, HPCl6 and HSbCl6 towards cyclic [PCl2N]n (n = 3, 4, 5, and 6) and polymeric [PCl2N]n follows in Chapter V. This chapter also qualitatively compares the acid strengths of the relatively unknown HPCl6 and HSbCl6 acids to the strengths of more commonly known superacids, such as HAlCl4, HAlBr4, HGaCl4 and superacids with carborane anions.

Ring opening polymerization (ROP) of hexachlorocyclotriphosphazene ([PCl2N]3) produces the phosphazene polymer that can later be functionalized for a variety of applications. However, the ROP process is irreproducible, and its mechanism is not well-understood. It had been proposed that Lewis acid catalysts might abstract a chloride from [PCl2N]3 and promote the bond breakage in the initial step of the ROP. In this research, the interactions of Group 13 Lewis acids with [PCl2N]3 were investigated. Adducts of [PCl2N]3 with AlCl3, AlBr3, and GaCl3 were successfully synthesized and characterized by X-ray crystallography and 31P and 1H VT NMR. Contrary to the previous reports, the Lewis acids did not remove the chloride from [PCl2N]3. Instead, they formed dative bonds with the nitrogen atom on [PCl2N]3. The adduct formation weakened the two P-N bonds on [PCl2N]3 that involved the nitrogen atom participating in the dative bond and its phosphorous neighbors on the ring.

Finite state test theory models the response behavior of an examinee and establishes the relationship between the ability of the examinee and the observed responses on a multiple-choice test. In finite state modeling, various assumptions about item characteristics and the examinees’ response strategies are made to estimate an examinee ability, and willingness to guess. Twelve sets of plausible assumptions about identifiability of distractors and examinee guessing strategies were adopted and the corresponding finite state models were actualized. Three consequences of the adoption of the 12 sets of assumptions were investigated: 1) the extent to which the resulting ability estimates rank ordered the examinees similarly, 2) variation in the magnitude of ability estimates and the estimated willingness to guess across the 12 models, and 3) the extent to which conclusions about examinees subgroups would differ according to the model employed. Also, conventional number-right scores were compared with the finite state scores with respect to the three outcomes just listed. All scoring methods rank ordered the examinees essentially the same. The magnitude of the finite state scores varied considerably across models mainly due to differing assumptions about the identifiability of distractors. Differing assumptions about examinee guessing strategy had surprisingly little effect on the magnitude of the ability estimates, though estimates of willingness to guess varied consistently according to the assumed strategies. Conclusions about group differences also varied across the models as a result of differing assumptions about both item characteristics and examinee guessing strategies.

The grinding models developed previously are concerned with size reduction only. Although they have proven to be useful in the simulation and design of grinding mills, they do not provide information on liberation which is the main objective of most comminution operations. In the present investigation, a population balance model describing the combined processes of size reduction and mineral liberation has been developed for batch grinding operation. The model parameters include conventional breakage rate and breakage distribution functions, along with a new parameter i.e., liberation function that is used to describe changes in particle composition. These parameters have been determined experimentally by examining mill products under optical microscope using a SEM-IPS image analyzer. The areal assays, obtained from the image analysis of monosized particle mounts, have been found to correspond quite closely to the actual chemical assays. It has been found that the method used to prepare particle mounts is critical in achieving accuracy. In the present work, it has been shown that the breakage characteristics of component minerals can be determined by examining the mill feeds and products using an image analyzer. The model parameter analysis has shown that while the breakage rate functions are sensitive to the grinding environment, breakage distribution functions are independent of it. Furthermore, the breakage distribution functions have been found to be normalizable with feed size, thus reducing the number of parameters that must be estimated. The study has also shown that both the breakage rate and the liberation function suggest a preferential breakage of sphalerite over dolomite gangue. The model has been validated by simulating the batch grinding of a sphalerite ore from ASARCO's Young Mine in eastern Tennessee. The model can predict the product size distributions for the total ore and its components, including gangue, sphalerite, and composite particles. An excellent agreement between the model predictions and the experimental results has been observed for both monosized and multisized feed materials. The model is capable of handling multiple classes of composite particles for a binary ore; however, the model has been verified against experimental results by considering only two composite classes. The method of determining liberation functions has also been discussed. The liberation function has been found to be useful for analyzing the liberation mechanisms of composite particles.

Cardiovascular disease remains the leading cause of mortality in Western world. Current treatments for vascular disease include vascular grafting and stenting. Owing to the limitations of current treatments, over the past few years a significant research effort has been directed towards the development of tissue engineered blood vessels (TEBV). However, a TEBV that matches the biological and biomechanical functionality of natural blood vessels has yet to be developed. One of the strategies employed in the development of TEBVs involves the use of decellularised or synthetic scaffolds, which are seeded with the patient’s own cells and physically conditioned in bioreactors, with a view to developing blood-vessel-equivalent functionality prior to implantation. Along this line, the physical conditioning in bioreactors needs to replicate the in vivo haemodynamic stimulation, in order to guide normal cellular function and appropriate graft remodelling and regeneration. However, the in vitro set up, with the cells seeded on to a decellularised or synthetic scaffold and subjected to pulsatile flow in a bioreactor, does not represent a physiological scenario. Even if the bioreactor is able to simulate physiological haemodynamic conditions at the macroscale, the stimulus that would be transferred to the microscale and sensed by the cells to regulate their function is likely to be different from the micro-stimulus sensed by the cells in vivo in a native blood vessel. Therefore, in order to appropriately guide cellular function in vitro it would be necessary to assess the level of micro-stimulus sensed by the native cells in the native blood vessel in vivo, with a view to simulating this micro-stimulus in artificial bioreactor environments for conditioning the cells that are seeded onto scaffolds with non-native histoarhitectures. However, this micro-stimulus that vascular cells are exposed to in vivo cannot be assessed experimentally. The advances in computing and software resources have enabled the use of computational modelling for conducting such assessments. The aim of this project was to develop computational models for assessing the stress and strain fields on the vascular tissue and cells at the macro- and micro-scales, which will assist the bioreactor conditioning towards the development of tissue engineered vascular grafts. The 3D macro-scale simulations involved fluid-structure interaction (FSI) analysis with main focus on the strain on the vascular wall, while the 2D micro-scale simulation involved finite element analysis (FEA), focused on the local strain variation. All simulations were based on relatively physiological structures after experimental assessment. The simulations were also compared against experimental findings for strain. Macro strain resulted in approximately 11% for FSI against 19% for experimental pressure test. However, the limitations of the experimental procedure overestimated the performed dilation. Moreover, the 2D FEA simulations performed under different material properties, as an attempt to approach more physiological conditions, and under uniaxial strain only. The variation in material properties indicated inhomogeneicity, as expected, and also seemed to replicate the local strain spread when compared to experimental findings. However, further investigation is needed, which will involve the development of 3D FEA models, more physiological material properties and biaxial stretching. Under these circumstances, more information may be extracted and eventually applied to the bioreactor conditioning. Nevertheless, the novel methodology developed in this project for the study of the strain at the micro-level allows the further investigation on the tissue micro-environment.