Bioconversion of α-Linolenic Acid into n-3 Long-Chain polyunsaturated fatty acid in hepatocytes and ad hoc cell culture optimisation

This study aimed to establish optimal conditions for a cell culture system that would allow the measurement of 18:3n-3 (ALA) bioconversion into n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA), and to determine the overall pathway kinetics. Using rat hepatocytes (FaO) as model cells, it was established that a maximum 20:5n-3 (EPA) production from 50 mM ALA initial concentration was achieved after 3 days of incubation. Next, it was established that a gradual increase in the ALA concentration from 0 up to 125mM lead to a proportional increase in EPA, without concomitant increase in further elongated or desaturated products, such as 22:5n-3 (DPA) and 22:6n-3 (DHA) in 3 day incubations. Of interest, ALA bioconversion products were observed in the culture medium. Therefore, in vitro experiments disregarding the medium fatty acid content are underestimating the metabolism efficiency. The novel application of the fatty acid mass balance (FAMB) method on cell culture system (cells with medium) enabled quantifying the apparent enzymatic activities for the biosynthesis of n-3 LC-PUFA. The activity of the key enzymes was estimated and showed that, under these conditions, 50% (Km) of the theoretical maximal (Vmax = 3654 mmol.g21 of cell protein.hour21) Fads2 activity on ALA can be achieved with 81 mM initial ALA. Interestingly, the apparent activity of Elovl2 (20:5n-3 elongation) was the slowest amongst other biosynthesis steps. Therefore, the possible improvement of Elovl2 activity is suggested toward a more efficient DHA production from ALA. The present study proposed and described an ad hoc optimised cell culture conditions and methodology towards achieving a reliable experimental platform, using FAMB, to assist in studying the efficiency of ALA bioconversion into n-3 LC-PUFA in vitro. The FAMB proved to be a powerful and inexpensive method to generate a detailed description of the kinetics of n-3 LC-PUFA biosynthesis enzymes activities in vitro.

Digital shimmer: popular music and the intimate nexus between fan and star

Conception of ‘star performance’ through popular music is stratified which generates diverse and often contradictory forms of thought. For example, stars and celebrities plausibly act as a ‘culture medium’ in which, through imagination, one’s identity is assembled, realised or constructed. What to become and how to be are questions we individually and collectively contend with throughout our lives to varying degrees (Maslow, 1954; 1968). Predominant use of digital technologies has seen the delivery of sound much altered. Music, be it Giuseppe Verdi’s La Traviata or Iron Maiden’s The Number of the Beast, once sourced via analogue legacy devices such as ‘old-school’ tape cassette or vinyl record is now a series of zero and one digits. Advocates argue that the key benefit of digitalisation is the ability to compress data because sound generates large files of information. The discourse of digitalisation begs the question of how a series of ones and zeros, albeit in a plethora of configurations, registers with listening bodies and affects ‘the sublime’. It is without doubt that some musical experiences afford indescribable, unlocatable sensation—even enchantment (as defined by Bennett, 2001: 5 and called forth by Redmond: 2014: 126). Such musical experiences might be in the presence of the performer or in their absence such as in the case of recorded music. In this context, any sense of ’real’ space and place is less definitive allowing for ‘special encounters’ to be imagined and felt. For these reasons, music and all that the use of the word might convey, the proposed notion of phaino-ken here, acts as the lens through which to examine the meaning and value of celebrity and star embodiment.

Fostering information security culture in small and medium size enterprises: an interpretive study in Australia

By having an effective organisational information security culture where employees intuitively protect corporate information assets, small and medium size enterprises (SMEs) could improve information security. However, previous research has largely overlooked the development of such a culture for SMEs, and the national context in which SMEs operate. The paper explores this topic and provides key findings from an interpretive Australian study based on a literature review, two focus groups and three case studies. A holistic framework is provided for fostering an information security culture in SMEs in a national setting. The paper discusses key managerial challenges for SMEs attempting to develop such a culture. The main findings suggest that Australian SME owners do not provide sufficient support for information security due to insufficient awareness of its importance and may also be affected by national attitudes to risk. The paper concludes that Australian SME owners may benefit from adopting a risk-based approach to information security and should be educated about the potential strategic role of information technology and information security. The paper also identifies the value and difficulty of promoting a behavioural and learning approach to information security to complement traditional technological and managerial approaches. Implications for theory and practice are discussed.

Establishing information security culture in Australian small and medium enterprises

This thesis develops a framework of key influences that must be considered in order to enable development of an information security culture in Australian small and medium enterprises. The study argues that, by ensuring that key influences are in place, an effective information security culture will evolve.