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With improved care, infants born preterm are likely to survive both in high and low-resource settings. However, rate of postnatal growth failure is known to be high around the world although studies in Southeast Asia are still lacking. Effective interventions are needed to ensure that preterm infants can grow optimally. Nutrition, as one of the most important aspects in the postnatal care of preterm infants should be the top priority. Application of feeding practices varies, due to the differing protocols in neonatal units and medical conditions of the infants. In my first study (Chapter 2), nutritional practices and intakes among preterm infants in the neonatal units in Malaysia and the UK are compared and the association with growth at discharge was analysed. Results have shown that a higher number of Malaysian infants received breast milk (Malaysia: 98%, UK: 76%, p=0.001) and parenteral nutrition (Malaysia: 80%, UK: 38%, p<0.001) during admission. Malaysian infants received more protein (3.0 vs 2.7g, p=0.004) and had fewer energy and protein deficits (-191.6 kcal/kg vs -254.5 kcal/kg, -11.4 g/kg vs -15.4 g/kg) on week 1-4 of life as compared to infants in the UK unit. Despite this, more than half of infants in both units were discharged with growth failure, defined as a change in weight-for-age Z-score (WAZ) of >-1.28. Infants who had a longer length of stay had a larger drop in WAZ in the Malaysia unit. This relationship was not found in the UK cohort where protein intake and protein energy ratio (PER) were the variable that associated with changes in WAZ between birth and discharge. From the first study, the differences in breast milk use between the neonatal units were highly apparent. Therefore, I designed the next study to look at breastfeeding in the UK neonatal unit in more detail (Chapter 3). Here, a retrospective observational study in a neonatal unit in the UK using the BadgerNet database was conducted on the prevalence of breastfeeding between 2017 and 2020. This included the duration when the COVID-19 pandemic had started, allowing me to investigate any changes of practices associated with it and the impacts on the prevalence of breastfeeding in the neonatal unit. Results have shown that there were fluctuations in the breast milk feeding prevalence during admission (adjusted OR of 0.70 (95% CI 0.44-1.12, p=0.140) and at discharge (adjusted OR of 0.96 (95% CI 0.62-1.47, p=0.844) during the early COVID-19 pandemic period as compared to the pre-pandemic period, but this was not significant. This could be due to the small sample size in this study which may not be sufficiently powered to detect a difference between the periods, or other factors such as the breastfeeding policies in the study unit which follows the WHO recommendations. The next study also involved the use of a database as a part of the study of feeding practices in neonatal units. Gastro-oesophageal reflux (GOR) is a common condition that affects feeding practices in preterm infants and may impact their growth. It is called gastro-oesophageal reflux disease (GORD) if it presents with complications. In this study (Chapter 4), I used the National Neonatal Research Database (NNRD) to describe patterns of GORD diagnosis and use of anti-reflux medications among preterm infants in England and Wales from 2010 to 2017. Results have shown that more infants receive anti-reflux medication (10-14% of infants) as compared to those who had a GORD diagnosis (4-5% of infants). There was a decreasing trend in the use of anti-reflux medications since 2010, with the most rapid decline occurring after 2013. From this chapter, the patterns of use of different types of anti-reflux medications including Histamine-2 receptor antagonists (H2RA) and proton pump inhibitors (PPI) were also demonstrated. In parallel to this work, I wanted to find out about the current practices and perspectives of management of GORD in preterm infants in the UK. For this, I conducted a two-part scoping survey which was undertaken as a patient and public involvement activity comprised of: i) health practitioners' perspectives on the management of GORD and anti-reflux medications use in neonatal units, and ii) parents' perspectives on the treatment of GORD received by preterm infants during admission in neonatal units (Chapter 5). This study demonstrated the diversity in opinions among health practitioners in determining the signs and symptoms related to GORD. However, self-reported strategies used in their clinical practice were quite consistent. The majority of respondents reported that they do not use anti-reflux medications and preferred a trial of a non-pharmacological approach before pharmacological management (n=80/154 (52%)). A few of the respondents noted that GORD is a self-resolving condition, and they would never treat it. In terms of pharmacological therapy, PPI and feed thickener with antacid (i.e. Gaviscon) were the two most popular (PPI: n=100/154 (65%), Gaviscon: n=93/154, (60%)) and prokinetics (n=27/154 (18%)) were the least medication used. The parents' survey generally showed that parents have a certain level of understanding of the importance of using non-pharmacological strategies on initiating the treatment for GORD. However, further information and reassurance are needed to explain to parents why using medications should not be viewed as the most direct method in managing GORD in these infants. In conclusion, my work has demonstrated findings in two main areas of neonatal research which affect all neonates (i.e. the importance of feeding and growth) and a clinical problem (i.e. GORD) that affects a large number of infants. Infants' characteristics and feeding practices were shown to be varied between the neonatal units studied in the UK and Malaysia and these could impact nutritional requirements and growth outcomes of preterm infants. Current nutritional practices often do not meet recommended intakes and affecting their growth at discharge, especially for protein in preterm infants. However, considering the small sample size and the exploratory nature of this study, the findings should be interpreted with cautions, while also taking into consideration that feeding plan, growth and discharge decision in the units is not a linear pathway and there are other external factors that might affect one pathway or another. In terms of the prevalence of breastfeeding in the neonatal unit in the UK, this study has shown that the effect of COVID-19 pandemic on the rate of breastfeeding was not apparent and the fluctuations were not statistically significant. Larger sample size with the inclusion of more study units might provide a better analysis of the variations observed. Lastly, in the study of GORD and the use of anti-reflux medications among preterm infants, I have shown a discordance between GORD diagnosis and the use of anti-reflux medications. This could be a reflection of difficulties in diagnosing the condition and the lack of evidence-based management strategies. The parents and health care professionals survey supported this. Further research should be guided to design clinical diagnostic tools and evidence-based strategies to manage GORD in preterm infants.

Phosphatidylinositol 5-phosphate 4-kinase (PIP4K) catalyses the formation of phosphatidylinositol 4,5 bisphosphate (PtdIns(4,5)P2) which is a messenger involved in important cellular signalling pathways including the PI3K/Akt/mTOR pathway and the phospholipase C pathway. Three isoforms of PIP4K have been identified, namely PIP4K2α, PIP4K2β, and PIP4K2, which have been shown to play roles in cellular activities such as growth, stress response, immune system regulation, and tumour formation. However, the exact mechanisms engaged by the kinases are still obscure. This study focused on investigating the role of PIP4K in modulating the immune system through regulatory T cells (Tregs), and in growth of cancer cells with inactivated p53. Findings from this study showed that PIP4K2β and 2 isoforms regulate PI3K/Akt/mTOR signalling in Tregs to control cell proliferation, survival, and immunosuppressive activity. This study also suggested that PIP4K controls FOXP3 expression, the master transcriptional regulator of Tregs through a novel PI3K/UHRF1/FOXP3 pathway. Previously PIP4K had been shown to play roles in cancer cell growth, and a discovery of possible synthetic lethal interaction with p53 in cancer cells has made this kinase a promising target for cancer therapy. Findings from this study indicate that the synthetic lethality of PIP4K and p53 is not present in all types of cancer. Rather, it is suggested to depend on the specific mutation of p53 and alteration in expression of PIP4K in the cells. Inhibition of PIP4K also regulates the PI3K/Akt pathway differently in different cancer cells. Together, findings from this study suggested that PIP4K modulates both the immune system and cancer cell growth, and its different role in regulating PI3K/Akt/mTOR pathway could be the key to understand how PIP4K modulates the systemic immune response, and how different cancers can benefit from the expression of this family of lipid kinases.

Viscous fingering is important in many applications and industries and can occur over a wide range of time and length scales. Examples include fluid separation using chromatography and carbon dioxide (CO2) sequestration. The particular type of viscous fingering discussed occurs in first contact miscible (FCM) displacements, which are often encountered in enhanced oil recovery applications such as CO2 injection. Viscous fingering is a highly non-linear phenomenon with a strong dependence on viscosity contrast, diffusion, dispersion and permeability variation. Its dynamics cannot be described analytically except at early time when the fingers grow independently of their neighbours. Predicting the growth of viscous fingering is challenging as it requires numerical simulation with high resolution to ensure physical diffussion and dispersion dominates over numerical errors. We begin our investigation with a quantitative assessment on the inherent errors in numerical simulations resulting from truncation of Taylor’s expansion when approximating the governing partial differential equations describing the flow in porous media. We study the effects of grid orientation and different numerical schemes. We show how the truncation error reduces the growth rate of immiscible viscous fingers for wavenumbers greater than 1 in all cases but does not affect the growth rate of higher wavenumber fingers as much as would be seen if capillary pressure were present. We then proceed to study the life-cycle of miscible fingering, from the early to late time regime. We use simple but effective methods to precisely detect nonlinear phenomena such as finger merging, coalescence and tip-splitting. By investigating the impacts of viscosity ratio and anisotropic dispersion on the fingering patterns, we propose how the scaling of non-linear growth can be made using the results from linear stability analysis. This subsequently allows us to predict when the late time regime will occur. Next we investigate how spatial variations in the permeability including channelling and highly correlated reservoirs influence the viscous fingering. We study how macroscopic efficiency is reduced due to bypassed-oil in channelised reservoirs, and attempt to capture this using a modified 1D Koval model. We use several metrics to provide demarcations between the type of heterogeneity and resulting flow regimes. Finally, we perform numerical simulations of polymer slug fingering using FCM simulator and black-oil simulator with Todd-Longstaff model. We show how the latter may suffer excessive numerical dispersion and we present a simple method to overcome this. Finally, we show that the miscible fingering at the back of the slug may be simplified by using a semi-analytical model that allows a rapid estimation of slug size required to maintain the integrity of the polymer slug.

Background: In Malaysia, information about contraception and safe sexual practices is still not delivered formally to young people in health clinics. Concurrently, unintended teenage pregnancies and the practice of 'baby dumping' are serious public health issues in Malaysia, particularly among young unmarried women. Research in other countries has highlighted several factors that influence the effectiveness of the provision of sexual and reproductive health (SRH) services to adolescents, including comprehensive sex education, friendly services and the use of contraception. Little is known about the provision of sexual healthcare for this group since it has not been examined in depth in a Malaysian context. Aims: This study set out to explore the views and experiences of primary healthcare professionals (HCPs) who deliver SRH services to unmarried adolescents in primary healthcare settings in Malaysia, with a view to identifying the factors that influence the provision of SRH services to unmarried adolescents. A further aim is to consider how the cultural and religious beliefs of HCPs might impact upon the SRH services they provide. Methods: A qualitative study informed by a pragmatic approach was utilised. Thirty-one HCPs were interviewed to understand their experiences of dealing with adolescents and also their views on current SRH services provision. The interviews were conducted over a period of seven months between October 2014 and April 2015, and the data were analysed using thematic analysis. I also critiqued the SRH educational material that intended to be used by HCPs when working with adolescents. The initial critique of the SRH educational material was carried out using a technique broadly informed by critical discourse analysis. Findings and discussion: The findings highlight that SRH services for adolescents are generally a low priority in Malaysia and that formal educational materials do little to address the issue of safe sex or unintended pregnancy. Furthermore the cultural and religious context creates tension for HCP's who provide SRH information and treatment to sexually active unmarried adolescents. Conclusion: The findings can contribute to a better understanding of SRH services provision for unmarried adolescents in Malaysia with a view to addressing more effectively the issues of unintended pregnancies in this group. The evidence from this study can be used in the development of strategies to improve the quality of care and facilitate changes in the provision of SRH services to adolescents in Malaysia.

The unique electrical and optical properties of graphene have attracted application as transparent electrodes, transistors and photodetectors. However, the small flake size of mechanical exfoliated graphene has limited its scalability to large area production. Recently, large area graphene is produced through chemical vapour deposition (CVD) and epitaxial growth method. CVD of graphene on insulator or metal-catalyst is considered low cost and process flexible. This is because graphene film quality and deposition rate can be controlled through process parameters such as temperature, gas flow rate and gas mixture. Large area CVD graphene on metal-catalyst such as Ni or Cu is amongst other established method but the need for processing steps, such as film transfer and metal etching can ultimately damage the graphene and affect device performance. Therefore, the research attention is now focused on catalyst free CVD graphene process on insulator materials such as silicon dioxide (SiO2). In this work, the nanocystalline graphene/graphite (NCG) films are synthesised in a mixture of methane (CH4) and hydrogen (H2) environment using radio frequency chemical vapour deposition (RF PECVD) without metal transition catalyst, deposited directly onto 150 mm diameter silicon wafer with an insulating substrate, such as SiO2, is presented. The as-deposited NCG films properties depend on deposition conditions such as growth temperature, growth time, pressure, mixtures or flow rates of precursor, RF power and substrate material. Initially, the growth temperatures are varied in the range of 600 °C to 850 °C, while keeping other deposition parameters unchanged, and subsequently the properties of the as-deposited NCG film is studied. The nanocrystalline nature of as-deposited film are analysed based on their Raman spectra, whereas the film thickness and sheet resistances are characterised using ellipsometry spectroscopy and a simple four point probe measurements respectively. The electrical properties of the NCG films are performed using I-V measurement on a simple two terminal device with titanium/nickel (Ni/Ti) contacts. Transmission line method (TLM) structures with Ni/Ti probe pads are also fabricated for contact and sheet resistances measurement purposes.

Metal pollutants such as copper released into the aqueous environment have been increasing as a result of anthropogenic activities, a topic causing global concern. Adsorption-based treatment technologies offer opportunities to remediate metal pollutants from municipal and industrial wastewater effluent. The aim of this work was to evaluate the capability of modified cellulose nanowhisker (CNW) adsorbents for the remediation of copper from water matrices under realistic conditions using response surface methodology (RSM) and artificial neural network (ANN) models. The first part of the study explored the preparation and characterisation of modified CNW adsorbents. It also focused on the stability of the modified CNW adsorbents at different time intervals under dry conditions (up to 28 days) and in the water matrix (up to 7 days). The results showed that the modified CNW adsorbents were stable at different time intervals under dry conditions and in the water matrix and proved that the functional groups were permanent and did not degrade under the tested conditions. The stability of these modified CNW adsorbents under these conditions, which is relevant from both the manufacturing and application perspectives, is reported for the first time in this study. The second part of the work focused on using copper as a case study for heavy metal pollution in a clean water matrix, to evaluate removal by modified CNWs under several conditions and ranges appropriate to wastewater treatment plants (WWTPs), using factorial experimental design. RSM and ANN models were employed in order to optimise the system and to create a predictive model to evaluate the Cu(II) removal performance by the modified CNW adsorbents. Moreover, unseen experiments not belonging to the training data set, located both inside and outside the test parameter system, were performed to test the model suitability. This is also novel, as generally only one or two parameter variations have been tested, without checking the chosen model suitability for parameters lying between the tested parameters, and certainly not for parameters lying outside the tested parameter space, as has been done in this study. The results obtained showed that the ANN model outperformed the RSM model when predicting copper removal from a clean water matrix. The Langmuir andFreundlich isotherm models were applied to the equilibrium data, and the results revealed that the Langmuir isotherm (R2 = 0.9998) had better correlation than the Freundlich isotherm (R2 = 0.9461). Experimental data was also tested in terms of kinetics studies using pseudo-first order and pseudo-second order kinetic models. The results showed that the pseudo-second-order model accurately described the kinetics of adsorption. The third part of the work was aimed at gaining a deeper understanding of the complexity and variability of the wastewater matrix, including evaluating the impact of the wastewater matrix temporally on adsorbent performance to remediate copper pollutant from a real-world wastewater matrix. This study has demonstrated that the wastewater matrix composition, which is both complex and variable, has an impact on adsorbent capability and performance. A benchmark study was adopted as a ‘new’ water quality parameter to inform on the effects of the wastewater matrix (wastewater composition and its variability) on the modified CNW adsorbent’s capability to remediate copper from this matrix. Since the process of adsorption from wastewater is often complicated due to the variation in wastewater composition, results obtained from the benchmark experiments were included as one of the independent variables in ANN modelling, unlike in other optimisation studies. The performance of the ANN and RSM models was statistically evaluated in terms of coefficient of determination (R2), absolute average deviation (AAD), and root mean squared error (RMSE) on predicted experimental outcomes. The ANN model including the variability of wastewater composition fitted the experimental data with excellent accuracy and better prediction (R2 = 0.9963) than both the ANN model that did not include this variability (R2 = 0.9945), and the RSM model (R2 = 0.9409). The outcome of this study showed that by supplying the ANN model with the data obtained from the benchmark experiments as the fourth independent variable, it was possible to improve the predictability of the ANN model. Continuous flow experiments for remediation of spiked Cu(II) from the wastewater matrix were conducted. However, the physical structure of modified CNW adsorbents renders them unsuitable for use in column operation. Therefore, a more detailed study of the mechanical properties of CNW adsorbents would be necessary in order to improve the strength and stability of the adsorbents. This work has demonstrated that modified CNW are promising adsorbents to remediate copper from water matrices under realistic conditions including wastewater complexity and variability. The use of models to predict the test parameter system and account for matrix variability when evaluating CNW adsorbents for remediating Cu from a real-world wastewater matrix may also provide the foundation for assessing other treatment technologies in the future.

Numerical models of insect flapping flight have previously been developed and used to simulate the performance of insect flight. These models were commonly developed via Blade Element Theory, offering efficient computation, thus allowing them to be coupled with optimisation procedures for predicting optimal flight. However, the models have only been used for simulating hover flight, and often neglect the presence of the induced flow effect. Although some models account for the induced flow effect, the rapid changes of this effect on each local wing element have not been modelled. Crucially, this effect appears in both axial and radial directions, which influences the direction and magnitude of the incoming air, and hence the resulting aerodynamic forces. This thesis describes the development of flapping wing models aimed at advancing theoretical tools for simulating the optimum performance of insect flight. Two models are presented: single and tandem wing configurations for hawk moth and dragonfly, respectively. These models are designed by integrating a numerical design procedure to account for the induced flow effects. This approach facilitates the determination of the instantaneous relative velocity at any given spanwise location on the wing, following the changes of the axial and radial induced flow effects on the wing. For the dragonfly, both wings are coupled to account for the interaction of the flow, particularly the fact that the hindwing operates in the slipstream of the forewing. A heuristic optimisation procedure (particle swarming) is used to optimise the stroke or the wing kinematics at all flight conditions (hover, level, and accelerating flight). The cost function is the propulsive efficiency coupled with constraints for flight stability. The vector of the kinematic variables consists of up to 28 independent parameters (14 per wing for a dragonfly), each with a constrained range derived from the maximum available power, the flight muscle ratio, and the kinematics of real insects; this will prevent physically-unrealistic solutions of the wing motion. The model developed in this thesis accounts for the induced flow, and eliminates the dependency on the empirical translation lift coefficient. Validations are shown with numerical simulations for the hover case, and with experimental results for the forward flight case. From the results obtained, the effect of the induced velocity is found to be greatest in the middle of the stroke. The use of an optimisation process is shown to greatly improve the flapping kinematics, resulting in low power consumption in all flight conditions. In addition, a study on dragonfly flight has shown that the maximum acceleration is dependent on the size of the flight muscle.

The reduction in government funding and increased competition within the sector has led to ‗marketisation‘ of higher education. Universities, especially those which operate at the international level, are increasingly aware of the need to understand the various needs and wants of their students in order to enhance the overall educational experience which consequently allow them to remain competitive in the global market. Perceived value is one of the key marketing concepts which the importance is widely acknowledged by both researchers and practitioners. Within the commercial sectors, customers‘ perception of value has been suggested to be the primary source for competitive advantage. Numerous studies have proven perceived value to be the precursor for customers‘ behaviours and attitude such as intention and decision to purchase, satisfaction, loyalty and willingness to recommend a particular offering. Nevertheless, only a handful of studies have explored the concept of perceived value within the higher education context and a majority of them were conducted using quantitative approaches. Furthermore, none of the existing studies had explored how this perception of value changes at different stages of consumption and whether this perception is affected by national cultures. This study is an attempt to fill the above gaps in existing body of knowledge. Given its global reputation and authoritative credential in business and management education, the Masters of Business Administration (MBA) was chosen for this investigation. Specifically, the main aim of this study is to understand how graduates from the UK, India and China perceived the value of their MBA. To achieve this aim, two frameworks were developed. The first framework conceptualised perceived value as a construct consisting of two high level components; perceived benefits (or ‗gets‘) and perceived sacrifices (or ‗gives‘). Both components were further broken into a number of sub-dimensions. Monetary and non-monetary sacrifices are the two sub-dimensions for the perceived sacrifices. Meanwhile the perceived benefits were divided into functional (i.e. usefulness of the degree and quality of the programme), social, emotional and epistemic benefits. The second framework conceptualised the dynamic nature of this perception. The MBA in this study was framed as an experiential service consisting of three stages of consumption. At the pre-MBA stage (i.e. prior to enrolment), perception of value is conceptualised as the antecedent for decision to purchase (i.e. enrolment). Meanwhile, perception of value during the programme is conceptualised as the antecedent for students‘ satisfaction with their educational experience. Finally, at the post-MBA stage this perception is conceptualised as the antecedent for students‘ satisfaction with their educational outcomes. Data for the present study was collected through in-depth interviews with twenty-eight participants who graduated from the Leeds University Business School‘s (LUBS) full-time MBA programme between the years 2000 to 2010. The British, Chinese and Indians were chosen for this investigation due to the fact that these are the three biggest pools of students for the UK full-time MBA programmes. Retrospective interview approach was adopted to explore the graduates‘ perception of the MBA‘s value at each stage of consumption. Data from the interviews were analyzed using template analysis approach. Findings from the study show that ascertaining the value of the MBA is a continuous evaluation process. In particular, perceived value of the MBA took different meanings at each phase of the ‗consumption‘ experience with different components dominating the perception. At the pre-MBA stage, the functional and epistemic benefits were found to be the main motivations for prospective students‘ intention to pursue the programme. The former relates to the ability to utilise the degree for attaining career agenda. Meanwhile the latter refers to the desire to learn and gain new knowledge and skills for personal development. The choice of MBA programme was dominated by the need to balance between the price or tuition fee (i.e. monetary sacrifices), quality and usefulness of the degree for career attainment (i.e. functional benefits). During the MBA programme, students mainly evaluate the value of the programme through its quality (i.e. functional benefit), especially the teaching and learning experience as well as the career support which relates closely to the epistemic and functional benefits. In addition, they also gain broader benefits in the form of broadened circle of friends and professional networks (i.e. social benefits) as well as better sense of self (i.e. emotional benefits). These benefits are compared against the sacrifices involved to determine their level of satisfaction with the programme. At the post-MBA stage, graduates initially based their evaluation of value mainly on the impacts of the programme on their career advancement (i.e. functional benefits). As they move on with their career, they continue to reflect on the sacrifices and begin to realise the broader benefits of the programme. This caused them to re-evaluate their initial perception. In addition to the above findings, the study also found that the perception of value in the higher education context is affected by nationality (i.e. culture), age and gender. This study contributed to the understanding of perceived value concept, especially in the context of higher education. The two frameworks developed for the study specify the components of perceived value concept and explains their inter-relationships at different stages of consumption. Data from the interviews provide empirical evidence for the i) personal and idiosyncratic, ii) situational or contextual, iii) comparative and iv) dynamic or temporal nature of the concept which previously have been discussed mainly at theoretical level. The findings also have some practical implications for the business school to improve their MBA programme and remain competitive in the global MBA market.

This thesis explores the influence of family business cultures (FBC) through three-circle model of family business by Gersick et al., (1997), entrepreneurial orientation (EO) by Covin and Slevin (1991) and the New Economic Policy (NEP) from 1971-1990 as the Malaysian government's intervention and affirmative policy on the survival of Malay (MFB) and Chinese (CFB) family businesses, specifically on micro- and small-sized family businesses. Since there was very little knowledge of the operation and survival of family business (FB) in the context of Malaysia across ethnicities, this research study takes a retrospective approach in reviewing secondary-source literature which covers the period from the era of British colonialism starting in the eighteenth century until the post-independence period, especially during the implementation of the NEP from 1971, in order to be able to gain a fair and adequate view of the socio-economic situations across the two major ethnicities i.e. the Malays and Chinese. In addition, two empirical studies were carried out in the Klang Valley as the fastest growing economic region and where the capital city of Malaysia, Kuala Lumpur, is located using the mixed-method research approach by combining both quantitative (Study 1) and qualitative (Study 2) research designs in order to derive more robust and reliable findings. The 226 MFB participants in the study completed a survey questionnaire designed to provide quantitative data, while a further ten samples, five each from MFB and CFB, undertook an in-depth interview of qualitative design. As well as entrepreneurs, the study was complemented by the inclusion of ten non-entrepreneurs, comprising two experts in the two different Malaysian ethnic businesses, two politicians from the ruling and opposition parties, two government policy makers and four bankers, including both commercial and government bankers in order to derive more conclusive understanding. The main findings revealed that the MFB and CFB were rooted differently in terms of their cultural resources, as the former were imbued with the religious beliefs of Islam while the latter practised Confucian cultural values in their businesses. Both ethnicities exhibited longer-term survival in their businesses succeeding beyond the critical first three years, but the CFB had the further advantage of strong bonding in terms of social capital networking within their ethnic group which surpassed that of the MFB, and this explained their dominance in the various businesses since the colonial period. A surprising result was the encouraging number of MFBs which had developed positive links with Chinese business networks, as well as the fact that both ethnicities exhibited similar characteristics in terms of EO. The findings on the effectiveness of the NEP’s implementation on the MFB’s and CFB’s survival were mixed in that there were both direct and indirect influences on their business survival, and that micro-sized businesses struggled more than small-sized businesses and that the more-educated owners gained an advantage in comparison with the less-educated in terms of access to micro and small financing schemes. This study advances the understanding of these issues in its theoretical, methodological and practical contributions; its limitations are acknowledged and suggestions for future research are recommended.

The ability of an organisation to transfer knowledge is one of the key sources of competitive advantage for many of today’s organisations (Argote, 2000). New knowledge is created through interactions between explicit and tacit knowledge (Nonaka and Takeuchi, 1995). From the distinction between explicit and tacit knowledge made by Polanyi’s (1966), it is clear that the former can be transferred with relative ease, particularly using recent advances in information technology. Transfer of tacit knowledge on the other hand, requires social interactions with peers, colleagues, mentors and supervisor (Lahti et al, 2002; Cavusgil et al, 2003). Difficulties associated with this have been referred to as ‘internal stickiness’ (Szulanski, 1996) and is believed to be due to several factors. This study examines difficulties associated with the transfer of managerial tacit knowledge in the relationships involving supervisor and subordinates who work as managers in the Malaysian public sector. After examining previous literature in the field it is hypothesised that the stickiness of knowledge transfer may be associated with the quality of leader member exchange relationships, especially between leaders and their ‘in-group’ versus ‘out-group’ members. For example, in-group relationships are associated with higher levels of trust, respect and obligation compared with out-group relations. Another construct known to be associated with the quality of dyadic relationships is cognitive style (Armstrong, 1999). Cognitive style refers to individual differences in ways of perceiving, organising and processing information and differences in ways in which individuals solve problems, take decisions and relate to others. The research employed a quantitative approach using survey methods. Instruments used in the study included a measure of knowledge transfer stickiness (Szulanski, 1996), Leader Member Exchange (LMX7) (Graen and Uhl-Bien, 1995), Tacit Knowledge Inventory for Managers (TKIM) (Wagner and Sternberg, 1989) and the Cognitive Style Index (CSI) (Allinson and Hayes, 1996). The survey was administered to 1200 managers in the Malaysian Public Sector and 344 completed surveys were returned representing a response rate of 28.7%. Results from a final sample size of 300 managers comprising supervisors and their immediate subordinates are reported. The study successfully determined the relationship between knowledge transfer stickiness, LMX, cognitive style and managerial tacit knowledge. As expected, high-quality LMX leads to higher quality exchanges and concomitant improvements in the transfer of managerial tacit knowledge. Moreover, as hypothesised, individual differences and similarities in cognitive style also influence the transfer of tacit knowledge between supervisor and subordinate. Practical implications are given and recommendation made for future research.

This thesis describes new models and investigations into switching transient phenomena related to the shunt reactors and the Mechanically Switched Capacitor with Damping Network (MSCDN) operations used for reactive power control in the transmission system. Shunt reactors and MSCDN are similar in that they have reactors. A shunt reactor is connected parallel to the compensated lines to absorb the leading current, whereas the MSCDN is a version of a capacitor bank that has been designed as a C-type filter for use in the harmonic-rich environment. In this work, models have been developed and transient overvoltages due to shunt reactor deenergisation were estimated analytically using MathCad, a mathematical program. Computer simulations were then undertaken using the ATP/EMTP program to reproduce both single-phase and three-phase shunt reactor switching at 275 kV operational substations. The effect of the reactor switching on the circuit breaker grading capacitor was also examined by considering various switching conditions. The main original achievement of this thesis is the clarification of failure mechanisms occurring in the air-core filter reactor due to MSCDN switching operations. The simulation of the MSCDN energisation was conducted using the ATP/EMTP program in the presence of surge arresters. The outcome of this simulation shows that extremely fast transients were established across the air-core filter reactor. This identified transient event has led to the development of a detailed air-core reactor model, which accounts for the inter-turn RLC parameters as well as the stray capacitances-to-ground. These parameters are incorporated into the transient simulation circuit, from which the current and voltage distribution across the winding were derived using electric field and equivalent circuit modelling. Further analysis of the results has revealed that there are substantial dielectric stresses imposed on the winding insulation that can be attributed to a combination of three factors. (i) First, the surge arrester operation during the MSCDN energisation, which causes steep voltage change at the reactor terminal. (ii) Second, the nonuniform voltage distribution, resulting in high stresses across the top inter-turn windings. (iii) Third, the rapid rate-of-change of voltage in the assumed worst-case reactor winding location. This is accompanied by a high dielectric (displacement) current through the inter-turn winding insulation. Work within this investigation proposes that a synergistic effect of high electric field and high dielectric current occurring at worst energisation, followed by the thermal effects of steady state operation contributes to the failure of air-core reactors used on the 400 kV MSCDN.

Generally, the growth of all forests accelerate as canopies develop as in young forests and declines substantially soon after maximum leaf area is attained. The causes of this decline trend are multiple. However, age and size are normally coupled growth. Therefore, an experimental manipulation has been done to separate the effects of size from those of age by using traditional grafting techniques. Genetically identical grafted seedlings were produced from scions taken from trees of four different age classes ranged from 4 to 162 years. The aim of this study is to investigate the effects of tree age and tree size on growth, physiology and water use of two broadleaf species by conducting three major experiments. Growth characteristics such as relative growth rate and growth efficiency were measured together with leaf-level gas exchanges and sap flow studies. Comparisons were established among results observed in the field with the ones obtained in the grafted seedlings. The results showed that relative growth rate and growth efficiency decreased substantially with increase in age of donor trees in the field. In contrast, these parameters seemed almost constant on grafted seedlings which are scions taken from different meristematic ages did not show the age-related trend after they were grafted onto the rootstocks. Similar patterns were also observed in net photosynthesis from leaf-level gas exchange and sap-flow-based parameters in both species. In general, these results suggested that size limitation to water and nutrient transport to the top of the canopy is a primary cause that triggered the declination in production of photosynthate and reduced growth of the trees, and/or increase in maintenance respiration with increasing in tree size rather than controlled by meristematic age.

With the increase in more service-oriented industries in the current economy, companies are having to reasses their assets in order to overcome competition. The lifestyles of people have become more fast-paced and along with the effects of globalisation, companies need to be able to adapt quickly to the ever-changing nature of consumer demands. Traditional material assets are no longer the only things that could be considered of value within the organisation. The skills, expertise and knowledge of the employees within the company could also be considered an asset that should be utilised efficiently to generate more income for the company. Furthermore, the advances in technology have created a society where information is utilised and modified at a rapid pace. Therefore, organisations; need to be aware of the knowledge that is within the company and utilise it efficiently to create services and products that would be attractive to the buying market. In the interest of knowledge and it s value within organisations, this research studies the capability of the organisation to manage the knowledge of their employees within the context of Knowledge Management( KM) processes. The research aims to discover how organisations identify the necessary knowledge required within the company and encourage their staff to become more knowledgeable. Moreover, this study includes questioning the extent to which companies have implemented KM strategies within the organisation that would assist them in the management of employee knowledge. Furthermore, the thesis aims to study how knowledge is retained and disseminated within the organisation. Lastly, the Human Resource support systems that would assist in the management of knowledge within the company are also studied. The research takes place within four different companies from four separate industries, namely the pharmaceutical, architecture, telecommunications and the oil and gas industries. The study is conducted using the qualitative multiple case-study method where key members within the chosen organisations are interviewed. It is discovered that although all the companies involved in the research are aware of the importance of their employees' knowledge and that they would like to manage it more efficiently, the organisations have not implemented any formal KM strategy. However, the companies have a variety of other policies and procedures that, when combined, could help the company to manage the knowledge base within the organisation. In addition, the findings of the study raise the issue of utilising support systems such as training and rewards as a means for encouraging employees to remain within the company as well as to contribute to the collective knowledge of the organisation. In conclusion, this research discovers possible points of interest regarding the issues relating to the KM process that should be taken into consideration when planning a KM strategy within an organisation.

To determine the prevalence of the sickle cell gene (HbS) in Yemen and amongst people from different regions of the country living in the capital, Sana'a City, cord blood samples from 1500 consented mothers were collected from hospitals in Sana'a City between July and December 2001. The names and original homes of the parents were recorded. Cationic HPLC analysis was used for screening while isoelectric focusing (IEF) and DNA- PCR were used to confirm haemoglobin S (HbS). Thirty-three samples were found to show Hb FAS giving an overall likely Hb S gene frequency of 0.011. The Hb S gene frequency varied with the part of the country from which the parents came. Amongst people from Taiz and Haja in the west the gene frequency was more than 0.04 but less than 0.004 amongst people from Ibb, adjacent to the governorate of Taiz. Of 66 chromosomes from babies carrying HbS, only 1.5% additionally carried the presence of-158 (C→T) G-gamma globin gene Xmm I site compared with 16.1% of 168 chromosomes from babies without Hb S from the same regions of the sickle cell trait samples identified in this study indicated that the beta S haplotype in not that associated with a milder course found in east Saudi Arabia. In addition to the absence of both Hind III/Ggamma and Hind III/Agamma beta globin polymorphic sites in 26 sickle cell trait samples suggesting the predominant of the African sickle cell haplotype (Benin) in Yemen. The results of this study thus show a higher Hb S gene frequency in the western coastal part of Yemen than in the central mountainous and eastern desert areas. The incidence of affected homozygous births may therefore reach 20/10,000 in the western coastal part of Yemen. A survey to evaluate health care of sickle cell patients was performed using 86 patients attending hospitals in Sanaa City, Yemen. The results showed that the clinical services provided to the sickle cell patients in Yemen were generally very poor. Limited health resources can best be invested in developing a program of education, screening and health care initially prioritising those communities residing in the western areas of Yemen with the highest Hb S gene frequency.

Laser Doppler flowmetry (LDF) has been used extensively over the last twenty years for measuring perfusion of the microcirculation in many clinical fields. One area that had not been studied extensively is in otology. In this study LDF was used to measure perfusion of the microcirculation in four sites of the external auditory meatus. Site 1: skin of the tragus. Site 2: skin of the cartilaginous part of the EAC. Site 3: skin of the deep bony part of the EAC. Site 4: the outer external surface of the tympanic membrane. This study was carried out in three groups: Control subjects (n=43) otitis externa patients (n=20) Myringoplasty patients (n=18). Measurements were made in a controlled environment with standard technique using a Perimed 5000 LDF instrument. Data were presented as arbitrary perfusion units (PU) set by the manufacturer. In the control group, the results showed that there was significant variation in the difference between the four sites with a descending site order of 3:2:1:4. The statistical distribution of the perfusion data showed that there was considerable variation between sites in their distribution patterns. No differences were apparent due to sex, age or core body temperature. There was no difference between right and left ear. There was no correlation between PU at each site, and intrasubject variability was not significant over two measures in n=13 subjects. In the otitis externa patients very large increases in the median PU values for all sites were seen with up to seven fold increases in perfusion being measured. The site order changed to 3:2:4:1. In the myringoplasty group no significant changes were seen pre- and post-operatively although individual patients exhibited substantial variation in individual pre- and post-site measurements. These results provide the first detailed measures of perfusion in the external auditory meatus and tympanic membrane. Whilst these results and the LDF technique are of principally experimental interest, they provide a systematic basis for the use of LDF as a clinical tool in otology.