Designed biodegradable hydrogel structures prepared by stereolithography using poly(ethylene glycol)/poly(D,L-lactide)-based resins

Designed three-dimensional biodegradable poly(ethylene glycol)/poly(D,L-lactide) hydrogel structures were prepared for the first time by stereolithography at high resolutions. A photopolymerisable aqueous resin comprising PDLLA-PEG-PDLLA-based macromer, visible light photo-initiator, dye and inhibitor in DMSO/water was used to build the structures. Porous and non-porous hydrogels with well-defined architectures and good mechanical properties were prepared. Porous hydrogel structures with a gyroid pore network architecture showed narrow pore size distributions, excellent pore interconnectivity and good mechanical properties. The structures showed good cell seeding characteristics, and human mesenchymal stem cells adhered and proliferated well on these materials.

Project-based organisations : overcoming lack of trust and social networks within small and medium project teams

In sustainable development projects, as well as other types of projects, knowledge transfer is important for the organisations managing the project. Nevertheless, knowledge transfer among employees does not happen automatically and it has been found that the lack of social networks and the lack of trust among employees are the major barriers to effective knowledge transfer. Social network analysis has been recognised as a very important tool for improving knowledge transfer in the project environment. Transfer of knowledge is more effective where it depends heavily on social networks and informal dialogue. Based on the theory of social capital, social capital consists of two parts: conduits network and resource exchange network. This research studies the relationships among performance, the resource exchange network (such as the knowledge network) and the relationship network (such as strong ties network, energy network, and trust network) at the individual and project levels. The aim of this chapter is to present an approach to overcoming the lack of social networks and lack of trust to improve knowledge transfer within project-based organisations. This is to be done by identifying the optimum structure of relationship networks and knowledge networks within small and medium projects. The optimal structure of the relationship networks and knowledge networks is measured using two dimensions: intra-project and inter-project. This chapter also outlines an extensive literature review in the areas of social capital, knowledge management and project management, and presents the conceptual model of the research approach.

Development of a PDLLA-based stereolithography resin for making tissue engineering scaffolds

The use of porous structures as tissue engineering scaffolds imposes high demands on the pore architecture. Stereolithography is a rapid prototyping method based on photo-polymerisation, that can be utilised to make 3D constructs with high spatial control. In this study, biodegradable resins were developed that can find application in stereolithography. Poly(D,L-lactide) (PDLLA) oligomers were synthesised and functionalised with methacrylate end-groups. By mixing the resulting macromers with a diluent, photo-initiator and inhibitor, lowviscosity resins were obtained that were photocrosslinked to yield stiff and strong degradable poly(lactide) networks. Also, porous scaffolds were fabricated on a stereolithography apparatus (SLA) from a nondegradable resin.

Designed poly(ethylene glycol)/poly(D,L-lactide)-based hydrogel structures prepared by stereolithography

Three-dimensional biodegradable poly(ethylene glycol)/poly(D,L-lactide) hydrogel structures were prepared by stereolithography. A photo-polymerisable liquid resin comprising PDLLA-PEG-PDLLA-based macromer, visible light photo-initiator, dye and inhibitor in DMSO/water was used to build the structures. Hydrogels with welldefined architectures and good mechanical properties were prepared. Hydrogel structures with a gyroid pore network architecture showed narrow pore size distributions, excellent pore interconnectivity and good mechanical properties. The structures showed good cell seeding characteristics, and human mesenchymal stem cells adhered and proliferated on these materials.

Sustainable urban development : formulation of indicator-based residential sustainability assessment framework for local level

Purpose–The purpose of this paper is to formulate a conceptual framework for urban sustainability indicators selection. This framework will be used to develop an indicator-based evaluation method for assessing the sustainability levels of residential neighbourhood developments in Malaysia. Design/methodology/approach–We provide a brief overview of existing evaluation frameworks for sustainable development assessment. We then develop a conceptual Sustainable Residential Neighbourhood Assessment (SNA) framework utilising a four-pillar sustainability framework (environmental, social, economic and institutional) and a combination of domain-based and goal-based general frameworks. This merger offers the advantages of both individual frameworks, while also overcoming some of their weaknesses when used to develop the urban sustainability evaluation method for assessing residential neighbourhoods. Originality/value–This approach puts in evidence that many of the existing frameworks for evaluating urban sustainability do not extend their frameworks to include assessing housing sustainability at a local level. Practical implications–It is expected that the use of the indicator-based Sustainable Neighbourhood Assessment framework will present a potential mechanism for planners and developers to evaluate and monitor the sustainability performance of residential neighbourhood developments.

Towards a unified method for the knowledge based urban development framework

Purpose–The growing debate in the literature indicates that the initiative to implement Knowledge Based Urban Development (KBUD) approaches in urban development process is neither simple nor quick. Many research efforts has therefore, been put forward to the development of appropriate KBUD framework and KBUD practical approaches. But this has lead to a fragmented and incoherent methodological approach. This paper outlines and compares a few most popular KBUD frameworks selected from the literature. It aims to identify some key and common features in the effort to achieve a unified method of KBUD framework. Design/methodology/approach–This paper reviews, examines and identifies various popular KBUD frameworks discussed in the literature from urban planners’ viewpoint. It employs a content analysis technique i.e. a research tool used to determine the presence of certain words or concepts within texts or sets of texts. Originality/value–The paper reports on the key and common features of a few selected most popular KBUD frameworks. The synthesis of the results is based from a perspective of urban planners. The findings which encompass a new KBUD framework incorporating the key and common features will be valuable in setting a platform to achieve a unified method of KBUD. Practical implications –The discussion and results presented in this paper should be significant to researchers and practitioners and to any cities and countries that are aiming for KBUD. Keywords – Knowledge based urban development, Knowledge based urban development framework, Urban development and knowledge economy