Passive control of a bi-ventricular assist device : an experimental and numerical investigation

For the last two decades heart disease has been the highest single cause of death for the human population. With an alarming number of patients requiring heart transplant, and donations not able to satisfy the demand, treatment looks to mechanical alternatives. Rotary Ventricular Assist Devices, VADs, are miniature pumps which can be implanted alongside the heart to assist its pumping function. These constant flow devices are smaller, more efficient and promise a longer operational life than more traditional pulsatile VADs. The development of rotary VADs has focused on single pumps assisting the left ventricle only to supply blood for the body. In many patients however, failure of both ventricles demands that an additional pulsatile device be used to support the failing right ventricle. This condition renders them hospital bound while they wait for an unlikely heart donation. Reported attempts to use two rotary pumps to support both ventricles concurrently have warned of inherent haemodynamic instability. Poor balancing of the pumps’ flow rates quickly leads to vascular congestion increasing the risk of oedema and ventricular ‘suckdown’ occluding the inlet to the pump. This thesis introduces a novel Bi-Ventricular Assist Device (BiVAD) configuration where the pump outputs are passively balanced by vascular pressure. The BiVAD consists of two rotary pumps straddling the mechanical passive controller. Fluctuations in vascular pressure induce small deflections within both pumps adjusting their outputs allowing them to maintain arterial pressure. To optimise the passive controller’s interaction with the circulation, the controller’s dynamic response is optimised with a spring, mass, damper arrangement. This two part study presents a comprehensive assessment of the prototype’s ‘viability’ as a support device. Its ‘viability’ was considered based on its sensitivity to pathogenic haemodynamics and the ability of the passive response to maintain healthy circulation. The first part of the study is an experimental investigation where a prototype device was designed and built, and then tested in a pulsatile mock circulation loop. The BiVAD was subjected to a range of haemodynamic imbalances as well as a dynamic analysis to assess the functionality of the mechanical damper. The second part introduces the development of a numerical program to simulate human circulation supported by the passively controlled BiVAD. Both investigations showed that the prototype was able to mimic the native baroreceptor response. Simulating hypertension, poor flow balancing and subsequent ventricular failure during BiVAD support allowed the passive controller’s response to be assessed. Triggered by the resulting pressure imbalance, the controller responded by passively adjusting the VAD outputs in order to maintain healthy arterial pressures. This baroreceptor-like response demonstrated the inherent stability of the auto regulating BiVAD prototype. Simulating pulmonary hypertension in the more observable numerical model, however, revealed a serious issue with the passive response. The subsequent decrease in venous return into the left heart went unnoticed by the passive controller. Meanwhile the coupled nature of the passive response not only decreased RVAD output to reduce pulmonary arterial pressure, but it also increased LVAD output. Consequently, the LVAD increased fluid evacuation from the left ventricle, LV, and so actually accelerated the onset of LV collapse. It was concluded that despite the inherently stable baroreceptor-like response of the passive controller, its lack of sensitivity to venous return made it unviable in its present configuration. The study revealed a number of other important findings. Perhaps the most significant was that the reduced pulse experienced during constant flow support unbalanced the ratio of effective resistances of both vascular circuits. Even during steady rotary support therefore, the resulting ventricle volume imbalance increased the likelihood of suckdown. Additionally, mechanical damping of the passive controller’s response successfully filtered out pressure fluctuations from residual ventricular function. Finally, the importance of recognising inertial contributions to blood flow in the atria and ventricles in a numerical simulation were highlighted. This thesis documents the first attempt to create a fully auto regulated rotary cardiac assist device. Initial results encourage development of an inlet configuration sensitive to low flow such as collapsible inlet cannulae. Combining this with the existing baroreceptor-like response of the passive controller will render a highly stable passively controlled BiVAD configuration. The prototype controller’s passive interaction with the vasculature is a significant step towards a highly stable new generation of artificial heart.

Management: Core concepts and applications

Building on the strengths of its popular previous edition Management: Core Concepts and Applications, 2nd Australasian edition has been thoroughly revised and updated to reflect the three keyaspects of contemporary undergraduate introductory management education: Management theory Concept application Skills development. The text's 16 chapters are presented in a lively and concise mannerideal for the typical 12 or 13 teaching weeks of a semester. Itsflexible framework allows instructors to teach students through the useof interactive tools such as case studies, exercises and projects.These action-oriented learning activities complement the text's solidfoundation of knowledge-based theory material. There is a balanced coverage of both small to medium sizedenterprises and larger multinational organisations operating inAustralia, New Zealand and the Asia-Pacific region. A critical thinkingperspective is integrated throughout the book, asking and encouragingstudents to analyse the theory in light of real-world examples. Each copy of the printed textbook comes with a free copy of the Wiley Desktop Edition:a full electronic version of the text that allows students to easilysearch for key concepts, create their own colour-coded highlights andmake electronic notes in the text for revision. Key themes of the text include: The importance of ethical and socially responsible management Recognition of the continuing need to cater for the increasing diversity of the workforce The importance of managing people, technology, knowledge and quality in achieving organisational goals An appreciation of the challenges and opportunities presented bythe ever changing environment in which contemporary managers operate.

Learning to reflect in the first year of legal education : the key to surviving legal education and legal practice

Lawyers and law students suffer significant rates of depression and substance abuse. This paper suggests that Law Schools have an obligation to assist students to develop the emotional intelligence necessary in order to cope with the stressful nature of legal practice. We draw on Schön’s discussion of the indeterminate zone of professional practice to suggest that reflective practice is the means by which students can become sufficiently emotionally intelligent to become balanced and happy lawyers. We suggest that incorporating reflective practice in intentional curriculum design in the first year of law is an effective first step in assisting students to develop the emotional intelligence necessary to survive the study and practice of law.

An exploratory study of innovation effectiveness measurement between Australian and Thai SMEs

The advantages of using a balanced approach to measurement of overall organisational performance are well-known. We examined the effects of a balanced approach in the more specific domain of measuring innovation effectiveness in 144 small to medium sized companies in Australia and Thailand. We found that there were no differences in the metrics used by Australian and Thai companies. In line with our hypotheses, we found that those SMEs that took a balanced approach were more likely to perceive benefits of implemented innovations than those that used only a financial approach to measurement. The perception of benefits then had a subsequent effect on overall attitudes towards innovation. The study shows the importance of measuring both financial and non-financial indicators of innovation effectiveness within SMEs and discusses ways in which these can be conducted with limited resources.

AITPM Email Newsletter Volume 0904, April 2009: Presidents Message

President’s Report Hello fellow AITPM members, A few weeks ago we saw another example of all levels of Government pulling together in real time to try to deal with a major transport incident, this time it was container loads of ammonium nitrate falling off the Pacific Adventurer during Cyclone Hamish and the associated major oil spill due to piercing of its hull off Moreton Bay in southern Queensland. The oil spill was extensive, affecting beaches and estuaries from Moreton Island north to the Sunshine Coast; a coastal stretch of at least 60km. We saw the Queensland Government, Brisbane, Moreton Bay and Sunshine Coast Regional Council crews deployed quickly once the gravity of the situation was realised to clean up toxic oil on beaches and prevent extensive upstream contamination. Environmental agencies public and private were quick to respond to help affected wildlife. The Navy’s HMAS Yarra and another minesweeper were deployed to search for the containers in the coastal area in an effort to have them salvaged before all ammonium nitrate could leach into and harm marine habitat, which would have a substantial impact not only on that environment but also the fishing industry. all of this during the final fortnight before a State election.) While this could be branded as a maritime problem, the road transport and logistics system was crucial to the cleanup. The private vehicular ferries were enlisted to transport plant and equipment from Brisbane to Moreton Island. The plant themselves, such as graders, were drawn from road building and maintenance inventory. Hundreds of Councils’ staff were released from other activities to undertake the cleanup. While it will take some time for us to know the long term impacts of this incident, it seems difficult to fault “grassroots” government crews and their private counterparts, such as Island tourism staff, in the initial cleanup effort. From a traffic planning and management perspective, we should also remember that this sort of incident has happened on road and rail corridors in the past, albeit on lesser scales. It underlines that we do need to continue to protect communities, commercial interests, and the environment through rigorous heavy vehicle management, planning and management of dangerous goods routesincluding rail corridors through urban areas), and carefully considered incident and disaster recovery plans and protocols. I’d like to close in reminding everyone again that AITPM’s flagship event, the 2009 AITPM National Conference, Traffic Beyond Tomorrow, is being held in Adelaide from 5 to 7 August. SA Branch President Paul Morris informs me that we have had over 50 paper submissions to date, from which a very balanced and informative programme of sessions has been prepared. www.aitpm.com has all of the details about how to register, sponsor a booth, session, etc. Best regards all, Jon Bunker

An exploration of knowledge management and intellectual capital in a nonprofit organisation context

In recent years, practitioners and researchers alike have turned their attention to knowledge management (KM) in order to increase organisational performance (OP). As a result, many different approaches and strategies have been investigated and suggested for how knowledge should be managed to make organisations more effective and efficient. However, most research has been undertaken in the for-profit sector, with only a few studies focusing on the benefits nonprofit organisations might gain by managing knowledge. This study broadly investigates the impact of knowledge management on the organisational performance of nonprofit organisations. Organisational performance can be evaluated through either financial or non-financial measurements. In order to evaluate knowledge management and organisational performance, non-financial measurements are argued to be more suitable given that knowledge is an intangible asset which often cannot be expressed through financial indicators. Non-financial measurement concepts of performance such as the balanced scorecard or the concept of Intellectual Capital (IC) are well accepted and used within the for-profit and nonprofit sectors to evaluate organisational performance. This study utilised the concept of IC as the method to evaluate KM and OP in the context of nonprofit organisations due to the close link between KM and IC: Indeed, KM is concerned with managing the KM processes of creating, storing, sharing and applying knowledge and the organisational KM infrastructure such as organisational culture or organisational structure to support these processes. On the other hand, IC measures the knowledge stocks in different ontological levels: at the individual level (human capital), at the group level (relational capital) and at the organisational level (structural capital). In other words, IC measures the value of the knowledge which has been managed through KM. As KM encompasses the different KM processes and the KM infrastructure facilitating these processes, previous research has investigated the relationship between KM infrastructure and KM processes. Organisational culture, organisational structure and the level of IT support have been identified as the main factors of the KM infrastructure influencing the KM processes of creating, storing, sharing and applying knowledge. Other research has focused on the link between KM and OP or organisational effectiveness. Based on existing literature, a theoretical model was developed to enable the investigation of the relation between KM (encompassing KM infrastructure and KM processes) and IC. The model assumes an association between KM infrastructure and KM processes, as well as an association between KM processes and the various levels of IC (human capital, structural capital and relational capital). As a result, five research questions (RQ) with respect to the various factors of the KM infrastructure as well as with respect to the relationship between KM infrastructure and IC were raised and included into the research model: RQ 1 Do nonprofit organisations which have a Hierarchy culture have a stronger IT support than nonprofit organisations which have an Adhocracy culture? RQ 2 Do nonprofit organisations which have a centralised organisational structure have a stronger IT support than nonprofit organisations which have decentralised organisational structure? RQ 3 Do nonprofit organisations which have a stronger IT support have a higher value of Human Capital than nonprofit organisations which have a less strong IT support? RQ 4 Do nonprofit organisations which have a stronger IT support have a higher value of Structural Capital than nonprofit organisations which have a less strong IT support? RQ 5 Do nonprofit organisations which have a stronger IT support have a higher value of Relational Capital than nonprofit organisations which have a less strong IT support? In order to investigate the research questions, measurements for IC were developed which were linked to the main KM processes. The final KM/IC model contained four items for evaluating human capital, five items for evaluating structural capital and four items for evaluating relational capital. The research questions were investigated through empirical research using a case study approach with the focus on two nonprofit organisations providing trade promotions services through local offices worldwide. Data for the investigation of the assumptions were collected via qualitative as well as quantitative research methods. The qualitative study included interviews with representatives of the two participating organisations as well as in-depth document research. The purpose of the qualitative study was to investigate the factors of the KM infrastructure (organisational culture, organisational structure, IT support) of the organisations and how these factors were related to each other. On the other hand, the quantitative study was carried out through an online-survey amongst staff of the various local offices. The purpose of the quantitative study was to investigate which impact the level of IT support, as the main instrument of the KM infrastructure, had on IC. Overall several key themes were found as a result of the study: • Knowledge Management and Intellectual Capital were complementary with each other, which should be expressed through measurements of IC based on KM processes. • The various factors of the KM infrastructure (organisational culture, organisational structure and level of IT support) are interdependent. • IT was a primary instrument through which the different KM processes (creating, storing, sharing and applying knowledge) were performed. • A high level of IT support was evident when participants reported higher level of IC (human capital, structural capital and relational capital). The study supported previous research in the field of KM and replicated the findings from other case studies in this area. The study also contributed to theory by placing the KM research within the nonprofit context and analysing the linkage between KM and IC. From the managerial perspective, the findings gave clear indications that would allow interested parties, such as nonprofit managers or consultants to understand more about the implications of KM on OP and to use this knowledge for implementing efficient and effective KM strategies within their organisations.

Recruiting older adults to health research studies : a systematic review

Objective: To provide a systematic review of papers comparing the effectiveness of different strategies to recruit older adults (aged 50 years and over) to participate in health research studies, to guide successful recruitment in future research. Methods: Four major databases were searched for papers published between 1995 and 2008 with: target group aged 50 years or over; participants allocated to receive one of two or more recruitment strategies; and an outcome measure of response rate or enrolment in study. Results: Twelve papers were included in the review. Conclusion: For postal questionnaires, recruitment strategies used with older adults had comparable outcomes to those used to recruit from the general population. For other types of studies, strategies involving face-to-face contact may be more effective than indirect methods, but this needs to be balanced against feasibility. Overall, little evidence on the topic exists and more rigorous investigation is necessary.

Rostering ambulance services

This paper developed a model for rostering ambulance crew in order to maximise the coverage throughout a planning horizon and minimise the number of ambulance crew. Rostering Ambulance Services is a complex task, which considers a large number of conflicting rules related to various aspects such as limits on the number of consecutive work hours, the number of shifts worked by each ambulance staff and restrictions on the type of shifts assigned. The two-stage models are developed using nonlinear integer programming technique to determine the following sub-problems: the shift start times; the number of staff required to work for each shift; and a balanced schedule of ambulance staff. At the first stage, the first two sub-problems have been solved. At the second stage, the third sub-problem has been solved using the first stage outputs. Computational experiments with real data are conducted and the results of the models are presented.

The Criminal Codes : Commentary and Materials

This edition has been substantially revised to increase overall clarity and to ensure a balanced examination of the criminal law in the 'Code' states, Queensland and Western Australia. The work has been brought up-to-date in all areas and provides valuable comment on the recent wide-reaching reforms to the law of homicide in Western Australia. Significant developments in both states discussed in this edition include: The abolition of wilful murder and infanticide, and the new definition of murder (WA); The introduction of the new offence of unlawful assault causing death (WA); The abolition of provocation to murder (WA), and whether this excuse still has a part to play (Qld); The reformulation of the excuse of self-defence, and the introduction of excessive self-defence (WA); The creation of offences for drink spiking (Qld and WA); and Current and proposed sentencing considerations (Qld and WA). Fundamental principles of the criminal law are illustrated throughout the book by selected extracts from the Codes and case law, while additional materials foster critical reflection on the law and the need for reform.

Developing a model of technology appropriation: A Marxian perspective

This paper explores the philosophical origins of appropriation of Information Systems (IS) using Marxian and other socio-cultural theory. It provides an in-depth examination of appropriation and its application in extant IS theory. We develop a three-tier model using Marx’s foundational concepts and from this generate four propositions that we test in an empirical example of IS in anesthesia. Using Marxian theory, this paper seeks common ground among existing theories of technology appropriation in IS research. This work contributes to IS research by (1) opening philosophical discussions on appropriation and the human ↔ technology nexus, (2) drawing on these varying perspectives to propose a general conceptualization of technology appropriation and (3) providing a starting point towards a general causal model of technology appropriation.

Employment Relations in Australia, 2nd Edition

The relationship between employers and employees has been one of the most hotly debated issues in Australia in recent times. Recent legislation such as the Workplace Relations Amendment (Work Choices) Act 2005 and the subsequent Fair Work Act 2009 provides stark evidence of this. The impact of these significant developments is explored and analysed in detail in the new edition of this popular text, complete with a balanced coverage of the often contrasting viewpoints of all stakeholders - from governments, unions and employer associations, through to individual employers and employees. The text outlines different approaches to understanding the nature of the employment relationship, with a contextual background as to how this relationship has changed and developed throughout our nation's history.

Diagramming the interior

Mark Taylor's new essay assesses the impact of the diagram on interior design from the late 19th century to the present. Taylor identifies the pop-cultural discourse of advice writing in both books and magazines as a starting point for his analysis. Drawing on diverse sources, his analysis focuses on texts relating to the dynamics of use and flexibility by Catherine Beecher, Harriet Beecher Stowe, Melusina Fay Peirce, Mary Haweis and Christine Frederick among others. The examples in these texts use the home, domestic housekeeping and kitchens as the sites and practices of intervention through which interior design innovations can be enacted. Taylor's analysis identified the innovations in both the social and the political aspects of space and the critique of static space behind these seemingly amateurish and innocuous texts. Identifying these contributions as early precursors of Modernism's open-plan and flexible, dynamic spaces, Taylor also interprets them with a critical concern for the oppositions and hierarchies that can exist in spatial design, and which are the hallmarks of recent Postmodern, phenomenological approaches to interior design and its theorisations. The progressive and subversive "paradigms for living" implicit in these diagrams can be argued to present a model of greater economic, social and political equality as well as representing a more balanced set of power relations in the home. Progressing through the 20th century to the present, Taylor's analysis shifts byond the dressed body and on to the more intimate rituals of the revealed body to further examine how diagrams of the interior, and the interior as a set of diagrams, are also mediators, sites and grounds for the design of social and sexual intimacy. Through a consideration of the link between design, indentity and intimacy (whether of the invisible, fashioned or sexualised body), the diagrms of interiors are reconfigured as radical and critical tools for an animate, material and emancipatory "redressing" of the balance between the body, identity, sexuality, gender, function, mis(use), aesthetics and the interior.

The skin awareness study : promoting thorough skin self-examination for skin cancer among men 50 years or older

Background: Incidence and mortality from skin cancers including melanoma are highest among men 50 years or older. Thorough skin self-examination may be beneficial to improve skin cancers outcomes.--------- Objectives: To develop and conduct a randomized-controlled trial of a video-based intervention to improve skin self-examination behavior among men 50 years or older.--------- Methods: Pilot work ascertained appropriate targeting of the 12-minute intervention video towards men 50 years or older. Overall, 968 men were recruited and 929 completed baseline telephone assessment. Baseline analysis assessed randomization balance and demographic, skin cancer risk and attitudinal factors associated with conducting a whole-body skin self-examination or receiving a whole-body clinical skin examination by a doctor during the past 12 months.--------- Results: Randomization resulted in well-balanced intervention and control groups. Overall 13% of men reported conducting a thorough skin self-examination using a mirror or the help of another person to check difficult to see areas, while 39% reported having received a whole-body skin examination by a doctor within the past 12 months. Confidence in finding time for and receiving advice or instructions by a doctor to perform a skin self-examination were among the factors associated with thorough skin self-examination at baseline.---------- Conclusions: Men 50 years or older can successfully be recruited to a video-based intervention trial with the aim reduce their burden through skin cancer. Randomization by computer generated randomization list resulted in good balance between control and intervention group and baseline analysis determined factors associated with skin cancer early detection behavior at baseline.

Elucidating the links between UV radiation and vitamin D synthesis : using an in vitro model

Ultraviolet radiation (UV) is the carcinogen that causes the most common malignancy in humans – skin cancer. However, moderate UV exposure is essential for producing vitaminDin our skin. VitaminDincreases the absorption of calcium from the diet, and adequate calcium is necessary for the building and maintenance of bones. Thus, low levels of vitamin D can cause osteomalacia and rickets and contribute to osteoporosis. Emerging evidence also suggests vitamin D may protect against falls, internal cancers, psychiatric conditions, autoimmune diseases and cardiovascular diseases. Since the dominant source of vitamin D is sunlight exposure, there is a need to understand what is a “balanced” level of sun exposure to maintain an adequate level of vitamin D but minimise the risks of eye damage, skin damage and skin cancer resulting from excessive UV exposure. There are many steps in the pathway from incoming solar UV to the eventual vitamin D status of humans (measured as 25-hydroxyvitamin D in the blood), and our knowledge about many of these steps is currently incomplete. This project begins by investigating the levels of UV available for synthesising vitamin D, and how these levels vary across seasons, latitudes and times of the day. The thesis then covers experiments conducted with an in vitro model, which was developed to study several aspects of vitamin D synthesis. Results from the model suggest the relationship between UV dose and vitamin D is not linear. This is an important input into public health messages regarding ‘safe’ UV exposure: larger doses of UV, beyond a certain limit, may not continue to produce vitamin D; however, they will increase the risk of skin cancers and eye damage. The model also showed that, when given identical doses of UV, the amount of vitamin D produced was impacted by temperature. In humans, a temperature-dependent reaction must occur in the top layers of human skin, prior to vitamin D entering the bloodstream. The hypothesis will be raised that cooler temperatures (occurring in winter and at high latitudes) may reduce vitamin D production in humans. Finally, the model has also been used to study the wavelengths of UV thought to be responsible for producing vitamin D. It appears that vitamin D production is limited to a small range of UV wavelengths, which may be narrower than previously thought. Together, these results suggest that further research is needed into the ability of humans to synthesise vitamin D from sunlight. In particular, more information is needed about the dose-response relationship in humans and to investigate the proposed impact of temperature. Having an accurate action spectrum will also be essential for measuring the available levels of vitamin D-effective UV. As this research continues, it will contribute to the scientific evidence-base needed for devising a public health message that will balance the risks of excessive UV exposure with maintaining adequate vitamin D.

How can entrepreneurial musicians use electronic social networks to diffuse their music

Principal Topic: ''In less than ten years music labels will not exist anymore.'' Michael Smelli, former Global COO Sony/BMG MCA/QUT IMP Business Lab Digital Music Think Thanks 9 May 2009, Brisbane Big music labels such as EMI, Sony BMG and UMG have been responsible for promoting and producing a myriad of stars in the music industry over the last decades. However, the industry structure is under enormous threat with the emergence of a new innovative era of digital music. Recent years have seen a dramatic shift in industry power with the emergence of Napster and other file sharing sites, iTunes and other online stores, iPod and the MP3 revolution. Myspace.com and other social networking sites are connecting entrepreneurial artists with fans and creating online music communities independent of music labels. In 2008 the digital music business internationally grew by around 25% to 3.7 Billion US-Dollar. Digital platforms now account for around 20% of recorded music sales, up from 15 % in 2007 (IFPI Digital music report 2009). CD sales have fallen by 40% since their peak levels. Global digital music sales totalled an estimated US$ 3 Billion in 2007, an increase of 40% on 2006 figures. Digital sales account for an estimated 15% of global market, up from 11% in 2006 and zero in 2003. The music industry is more advanced in terms of digital revenues than any other creative or entertainment industry (except games). Its digital share is more than twice that of newspapers (7%), films (35) or books (2%). All these shifts present new possibilities for music entrepreneurs to act entrepreneurially and promote their music independently of the major music labels. Diffusion of innovations has a long tradition in both sociology (e.g. Rogers 1962, 2003) and marketing (Bass 1969, Mahajan et al., 1990). The context of the current project is theoretically interesting in two respects. First, the role of online social networks replaces traditional face-to-face word of mouth communications. Second, as music is a hedonistic product, this strongly influences the nature of interpersonal communications and their diffusion patterns. Both of these have received very little attention in the diffusion literature to date, and no studies have investigated the influence of both simultaneously. This research project is concerned with the role of social networks in this new music industry landscape, and how this may be leveraged by musicians willing to act entrepreneurially. Our key research question we intend to address is: How do online social network communities impact the nature, pattern and speed that music diffuses? Methodology/Key Propositions : We expect the nature/ character of diffusion of popular, generic music genres to be different from specialized, niche music. To date, only Moe & Fader (2002) and Lee et al. (2003) investigated diffusion patterns of music and these focus on forecast weekly sales of music CDs based on the advance purchase orders before the launch, rather than taking a detailed look at diffusion patterns. Consequently, our first research questions are concerned with understanding the nature of online communications within the context of diffusion of music and artists. Hence, we have the following research questions: RQ1: What is the nature of fan-to-fan ''word of mouth'' online communications for music? Do these vary by type of artist and genre of music? RQ2: What is the nature of artist-to-fan online communications for music? Do these vary by type of artist and genre of music? What types of communication are effective? Two outcomes from research social network theory are particularly relevant to understanding how music might diffuse through social networks. Weak tie theory (Granovetter, 1973), argues that casual or infrequent contacts within a social network (or weak ties) act as a link to unique information which is not normally contained within an entrepreneurs inner circle (or strong tie) social network. A related argument, structural hole theory (Burt, 1992), posits that it is the absence of direct links (or structural holes) between members of a social network which offers similar informational benefits. Although these two theories argue for the information benefits of casual linkages, and diversity within a social network, others acknowledge that a balanced network which consists of a mix of strong ties, weak ties is perhaps more important overall (Uzzi, 1996). It is anticipated that the network structure of the fan base for different types of artists and genres of music will vary considerably. This leads to our third research question: RQ3: How does the network structure of online social network communities impact the pattern and speed that music diffuses? The current paper is best described as theory elaboration. It will report the first exploratory phase designed to develop and elaborate relevant theory (the second phase will be a quantitative study of network structure and diffusion). We intend to develop specific research propositions or hypotheses from the above research questions. To do so we will conduct three focus group discussions of independent musicians and three focus group discussions of fans active in online music communication on social network sites. We will also conduct five case studies of bands that have successfully built fan bases through social networking sites (e.g. myspace.com, facebook.com). The idea is to identify which communication channels they employ and the characteristics of the fan interactions for different genres of music. We intend to conduct interviews with each of the artists and analyse their online interaction with their fans. Results and Implications : At the current stage, we have just begun to conduct focus group discussions. An analysis of the themes from these focus groups will enable us to further refine our research questions into testable hypotheses. Ultimately, our research will provide a better understanding of how social networks promote the diffusion of music, and how this varies for different genres of music. Hence, some music entrepreneurs will be able to promote their music more effectively. The results may be further generalised to other industries where online peer-to-peer communication is common, such as other forms of entertainment and consumer technologies.