High performance additive manufactured scaffolds for bone tissue engineering application

This study demonstrates the feasibility of additive manufactured poly(3-caprolactone)/silanized tricalcium phosphate (PCL/TCP(Si)) scaffolds coated with carbonated hydroxyapatite (CHA)-gelatin composite for bone tissue engineering. In order to reinforce PCL/TCP scaffolds to match the mechanical properties of cancellous bone, TCP has been modified with 3-glycidoxypropyl trimethoxysilane (GPTMS) and incorporated into PCL to synthesize a PCL/TCP(Si) composite. The successful modification is confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis. Additive manufactured PCL/TCP(Si) scaffolds have been fabricated using a screw extrusion system (SES). Compression testing demonstrates that both the compressive modulus and compressive yield strength of the developed PCL/TCP(Si) scaffolds fall within the lower ranges of mechanical properties for cancellous bone, with a compressive modulus and compressive yield strength of 6.0 times and 2.3 times of those of PCL/TCP scaffolds, respectively. To enhance the osteoconductive property of the developed PCL/TCP(Si) scaffolds, a CHA-gelatin composite has been coated onto the scaffolds via a biomimetic co-precipitation process, which is verified by using scanning electron microscopy (SEM) and XPS. Confocal laser microscopy and SEM images reveal a most uniform distribution of porcine bone marrow stromal cells (BMSCs) and cellsheet accumulation on the CHA-gelatin composite coated PCL/TCP(Si) scaffolds. The proliferation rate of BMSCs on the CHA-gelatin composite coated PCL/TCP(Si) scaffolds is 2.0 and 1.4 times higher compared to PCL/TCP(Si) and CHA coated PCL/TCP(Si) scaffolds, respectively, by day 10. Furthermore, the reverse transcription polymerase chain reaction (RT-PCR) and western blot analyses reveal that CHA-gelatin composite coated PCL/TCP(Si) scaffolds stimulate osteogenic differentiation of BMSCs the most compared to the other scaffolds. In vitro results of SEM, confocal microscopy and proliferation rate also show that there is no detrimental effect of GPTMS modification on biocompatibility of the scaffolds.

Quantifying variability within technique and performance in elite fast bowlers : is technical variability dysfunctional or functional?

In fast bowling, cricketers are expected to produce a range of delivery lines and lengths while maximising ball speed. From a coaching perspective, technique consistency has been typically associated with superior performance in these areas. However, although bowlers are required to bowl consistently, at the elite level they must also be able to vary line, length and speed to adapt to opposition batters’ strengths and weaknesses. The relationship between technique and performance variability (and consistency) has not been investigated in previous fast bowling research. Consequently, the aim of this study was to quantify both technique (bowling action and coordination) and performance variability in elite fast bowlers from Australian Junior and National Pace Squads. Technique variability was analysed to investigate whether it could be classified as functional or dysfunctional in relation to speed and accuracy.

Development sites in the empty city : from picture book to performance

Picturebooks invite performance every time they are read. What happens to them when they’re adapted for live performance? This ongoing practice led research project (2008-) regenerates and transforms picturebook The Empty City (Hachette/Livre 2007) by David Megarrity and Jonathon Oxlade into a live experience. In this rebuilding, interanimation of text and illustration on the picturebook page suddenly open up into a new and complex structure incorporating composition of music, animation, live action, projected image and performing objects. The presenter is the creator of both the source text and writer/composer of the adaptation, providing a unique vantage point that draws on sources from both within and without the creative process up to and including audience reception. From the foundations up, this paper’s focus is on deep, muddy sites of development in the adaptation process, unearthed treasures, and how perceptions of fear and safety push, sway and stress the building of a new performance work for children in content, form and process.

Maximising the manufacturer performance value through lean initiatives using cost based model

Numerous tools and techniques have been developed to eliminate or reduce waste and carry out lean concepts in the manufacturing environment. However, appropriate lean tools need to be selected and implemented in order to fulfil the manufacturer needs within their budgetary constraints. As a result, it is important to identify manufacturer needs and implement only those tools, which contribute maximum benefit to their needs. In this research a mathematical model is proposed for maximising the perceived value of manufacturer needs and developed a step-by-step methodology to select best performance metrics along with appropriate lean strategies within the budgetary constraints. With the help of a case study, the proposed model and method have been demonstrated.

Photocatalytic hydrogen production with iron oxide under solar irradiation

As solar hydrogen is a sustainable and environmental friendly energy carrier, it is considered to take the place of fossil fuels in the near future. Solar hydrogen can be generated by splitting of water under solar light illumination. In this study, the use of nanostructured hematite thin-film electrodes in photocatalytic water splitting was investigated. Hematite (á-Fe2O3) has a narrow band-gap of 2.2 eV, which is able to utilise approximately 40% of solar radiation. However, poor photoelectrochemical performance is observed for hematite due to low electrical conductivity and a high rate of electron-hole recombination. An extensive review of useful measures taken to overcoming the disadvantages of hematite so as to enhance its performance was presented including thin-film structure, nanostructuring, doping, etc. Since semiconductoring materials which exhibit an inverse opal structure are expected to have a high surface-volume ratio, unique optical characteristics and a shorter distance for photogenerated holes to travel to the electrode/electrolyte interface, inverse opals of hematite thin films deposited on FTO glass substrate were successfully prepared by doctor blading using PMMA as a template. However, due to the poor adhesion of the films, an acidic medium (i.e., 2 M HCl) was employed to significantly enhance the adhesion of the films, which completely destroyed the inverse opal structure. Therefore, undoped, Ti and Zn-doped hematite thin films deposied on FTO glass substrate without an inverse opal structure were prepared by doctor blading and spray pyrolysis and characterised using SEM, EDX, XRD, TGA, UV-Vis spectroscopy and photoelectrochemical measurements. Regarding the doped hematite thin films prepared by doctor blading, the photoelectrochemical activity of the hematite photoelectrodes was improved by incorporation of Ti, most likely owing to the increased electrical conductivity of the films, the stabilisation of oxygen vacancies by Ti4+ ions and the increased electric field of the space charge layer. A highest photoresponse was recorded in case of 2.5 at.% Ti which seemed to be an optimal concentration. The effect of doping content, thickness, and calcination temperature on the performance of the Ti-doped photoelectrodes was investigated. Also, the photoactivity of the 2.5 at.% Ti-doped samples was examined in two different types of electrochemical cells. Zn doping did not enhance the photoactivity of the hematite thin films though Zn seemed to enhance the hole transport due to the slow hole mobility of hematite which could not be overcome by the enhancement. The poor performance was also obtained for the Ti-doped samples prepared by spray pyrolysis, which appeared to be a result of introduction of impurities from the metallic parts of the spray gun in an acidic medium. Further characterisation of the thin-film electrodes is required to explain the mechanism by which enhanced performance was obtained for Ti-doped electrodes (doctor blading) and poor photoactivity for Zn and Ti-doped samples which were synthesised by doctor blading and spray pyrolysis, respectively. Ti-doped hematite thin films will be synthesised in another way, such as dip coating so as to maintain an inverse opal structure as well as well adhesion. Also, a comparative study of the films will be carried out.

Consumers’ intentions to adopt 3G in regional cities in China : a comparative study

Rapid mobile technological evolution and the large economic stake in commercial development of mobile technological innovation make it necessary to understand consumers' motivations towards the latest advanced and updated technologies and services. 3G (the third generation of mobile communication technology) recently started its commercial development in the world‘s largest mobile communication market, China, after being delayed for a few years. Although China fell behind in commercially developing 3G, it is difficult to ignore studying this area, given the size of the market and promising future developments. This market deserves focused research attention, especially in terms of consumer behaviour towards the adoption of mobile technological innovation. Thus, the program of research in this thesis was designed to investigate how Chinese consumers respond to the use of this newly launched mobile technological innovation, with a focus on what factors affect their 3G adoption intentions. It aimed to yield important insights into Chinese consumers‘ innovation adoption behaviours and to contribute to marketing and innovation adoption research. Furthermore, it has been documented that Chinese consumers vary widely between regions in dialect, lifestyle, culture, purchasing power and consumption attitudes. Based on economic development and local culture, China can be divided geographically into distinctive regional consumer markets. Consequently, the results of consumer behaviour research in one region may not necessarily be extrapolated to other regions. In order to better understand Chinese consumers, the disparities between regions should not be overlooked. Therefore, another objective of this program of research was to examine regional variances in consumers' innovation adoption, specifically to identify the similarities and differences in factors influencing 3G adoption, contributing to intra-cultural studies. An extensive literature review identified two gaps: current China-based innovation adoption research studies are limited in providing adequate prediction and explanation of Chinese consumers' intentions to adopt 3G; and there was limited knowledge about the differences between regional Chinese consumers in innovation adoption. Two research questions therefore were developed to address these gaps: 1) What factors influence Chinese consumers' intentions to adopt 3G? 2) How do Chinese consumers differ between regional markets in the relative influence of the factors in determining their intentions to adopt 3G? In accordance with postpositivist research philosophy, two studies were designed to answer the research questions, using mixed methods. To meet the research objectives, the two studies were both conducted in three regional cities, namely Beijing, Shanghai and Wuhan, centred in the three regions of North China, East China and Central China respectively, with sufficient cultural and economical regional variances. Study One was an exploratory study with qualitative research methods. It involved 45 in-depth interviews in the three research cities to gain rich insights into the research context from natural settings. Eight important concepts related to 3G adoption were generated from analysis of the interview data, namely utilitarian expectation, hedonic expectation, status gains, status loss avoidance, normative influence, external influence, cost and quality concern. The concepts of social loss avoidance and quality concern were two unique findings, whereas the other concepts were similar to the findings in Western innovation adoption studies. Moreover, variances in 3G adoption between three groups of regional consumers were also identified, focusing on the perceptions of two concepts, namely status gains and normative influence. The conceptual research model was then developed incorporating the eight concepts plus the dependent variable of adoption intention. The hypothesized relationships between the nine constructs and hypotheses about the differences between regional consumers in 3G adoption were informed by the findings of Study One and the literature reviewed. Study Two was a quantitative study involving a web-based survey and statistical analysis procedure. The web-based survey attracted 800 residents from the three research cities, 270 from Beijing, 265 from Shanghai and 265 from Wuhan. They comprised three research samples for this study and consequently three sets of data were obtained. The data was analysed by Structural Equation Modelling together with Multi-group Analysis. The analysis confirmed that the concepts generated in Study One were influential factors affecting Chinese consumers' 3G adoption intention, with the exception of the concept external influence. Differences were found between the samples in the three research cities in the effect of hedonic expectation, status gains, status loss avoidance and normative influence on 3G adoption intention. The two Studies undertaken in this thesis contributed a better understanding of Chinese consumers' intentions to adopt advanced mobile technological innovation, namely 3G, in three regional markets. This knowledge contributes to innovation adoption and intra-cultural research, as well as consumer behaviour theory. It is also able to inform international and domestic telecommunication companies to develop and deliver more effective marketing strategies across Chinese regional markets. Limitations in the research were identified in terms of the sampling techniques used and the design of the two Studies. Future research was suggested in other Chinese regional markets and into consumer adoption of other types of mobile technological innovations.

The determinants of corporate sustainability performance

This paper investigates the factors that drive high levels of corporate sustainability performance (CSP), as proxied by membership of the Dow Jones Sustainability World Index. Using a stakeholder framework, we examine the incentives for US firms to invest in sustainability principles and develop a number of hypotheses that relate CSP to firm-specific characteristics. Our results indicate that leading CSP firms are significantly larger, have higher levels of growth and a higher return on equity than conventional firms. Contrary to our predictions, leading CSP firms do not have greater free cash flows or lower leverage than other firms.

Thermal performance optimization of building aspect ratio and south window size in five cities having different climatic characteristics of Turkey

The aim of the study is to establish optimum building aspect ratios and south window sizes of residential buildings from thermal performance point of view. The effects of 6 different building aspect ratios and eight different south window sizes for each building aspect ratio are analyzed for apartments located at intermediate floors of buildings, by the aid of the computer based thermal analysis program SUNCODE-PC in five cities of Turkey: Erzurum, Ankara, Diyarbakir, Izmir, and Antalya. The results are evaluated in terms of annual energy consumption and the optimum values are driven. Comparison of optimum values and the total energy consumption rates is made among the analyzed cities.

Improving the performance of facial expression recognition using dynamic, subtle and regional features

Human facial expression is a complex process characterized of dynamic, subtle and regional emotional features. State-of-the-art approaches on facial expression recognition (FER) have not fully utilized this kind of features to improve the recognition performance. This paper proposes an approach to overcome this limitation using patch-based ‘salient’ Gabor features. A set of 3D patches are extracted to represent the subtle and regional features, and then inputted into patch matching operations for capturing the dynamic features. Experimental results show a significant performance improvement of the proposed approach due to the use of the dynamic features. Performance comparison with pervious work also confirms that the proposed approach achieves the highest CRR reported to date on the JAFFE database and a top-level performance on the Cohn-Kanade (CK) database.

Primary students' performance on map tasks : the role of context

This study investigated the longitudinal performance of 583 students on six map items that were represented in various graphic forms. Specifically, this study compared the performance of 7-9-year-olds (across Grades 2 and 3) from metropolitan and non-metropolitan locations. The results of the study revealed significant performance differences in favour of metropolitan students on two of six map tasks. Implications include the need for teachers in non-metropolitan locations to ensure that their students do not overly fixate on landmarks represented on maps but rather consider the arrangement of all elements encompassed within the graphic.

The impact of the Malaysian code on corporate governance: compliance, institutional investors and stock performance

In 2001, the Malaysian Code on Corporate Governance (MCCG) became an integral part of the Bursa Malaysia Listing Rules, which requires all listed firms to disclose the extent of compliance with the MCCG. Our panel analysis of 440 firms from 1999 to 2002 finds that corporate governance reform in Malaysia has been successful, with a significant improvement in governance practices. The relationship between ownership by the Employees Provident Fund (EPF) and corporate governance has strengthened during the period subsequent to the reform, in line with the lead role taken by the EPF in establishing the Minority Shareholders Watchdog Group. The implementation of MCCG has had a substantial effect on shareholders' wealth, increasing stock prices by an average of about 4.8%. Although there is no evidence that politically connected firms perform better, political connections do have a significantly negative effect on corporate governance, which is mitigated by institutional ownership.