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The work reported here forms part of a UK Joint Information Systems Committee (JISC) funded project (BL4ACE) (http://bl4ace.tvu.ac.uk/). This project built on previous work that evaluated the effectiveness of a learning design to underpin academic competence in a Business Studies degree. A significant concern of the blended learning design was to scaffold independent learning activities by incorporating and reusing interactive Reusable Learning Objects (RLOs) within a Virtual Learning Environment (VLE). This paper reports on improvements in learner experience and performance following the transfer of the established Business Studies learning design across subject domains to a Science module. It reports on the enhancement of both modules by reusing and repurposing existing RLOs from other Institutions, and evaluates the experiences of both Business and Science students using the support provided through the interactive learning materials. (Contains 1 table and 5 figures.)

Results show that the respiratory ultradian oscillation in Saccharomyces cerevisiae is temperature dependent and it is lost when the temperature is altered beyond the temperature compensation region. Furthermore, changing the range of dilution rates also affect the mode of oscillation, suggesting that the oscillation in respiratory output is clock-dependent.

Abstract Background Outbreaks of food poisoning associated with drinking un-pasteurised apple juice contaminated with enterohaemorrhagic Escherichia coli O157:H7 are a cause of serious illness and occasionally death. Whilst a well-established heat process (pasteurisation) will readily eliminate the pathogen, some consumers are demanding more fresh-like foods that have not been subjected to processing methods that are perceived as severe and may lead to loss of flavour and vitamins. Therefore, alternative methods are being investigated to replace pasteurisation and improve the safety of minimally-processed juices. The addition of natural antimicrobial substances such as the phenolic substances carvacrol and p-cymene (derived from the essential oils of herbs and spices) provides a potential new route to assure safety and extend the shelf-life of raw fruit juices. The aim of this study was to evaluate the addition of very low concentrations (0.25–1.25 mM) of carvacrol and p-cymene both individually and in combination as a novel means of controlling Escherichia coli O157:H7 in un-pasteurised apple juice. Results When inoculated at a level of 4 log CFU/ml into un-pasteurised apple juice (pH 3.20 ± 0.06), Escherichia coli O157:H7 survived for up to 3 and 19 days at 25° and 4°C, respectively. Treatment of the juice with 1.25 mM carvacrol or p-cymene reduced the numbers of E. coli O157:H7 to undetectable levels within 1–2 days at both storage temperatures. The effective concentrations of carvacrol could be reduced even further by combining it at 0.5 mM with cymene at 0.25 mM. The phenolic compounds were biocidal against both spoilage yeasts and E. coli O157:H7 thereby increasing the shelf-life and improving the safety of un-pasteurised apple juice, particularly when stored at chill temperatures. Conclusion The results showed that the natural antimicrobial compounds carvacrol and p-cymene could potentially be used to extend the shelf life and improve the safety margins in un-pasteurised chilled fruit juices.

An introduction is presented in which the editor discusses various papers within the issue on topics including the antimicrobial properties of sulphur and silver nanoparticles, antimicrobial properties of zinc nanoparticles, and inhibition of bacterial growth using silver nanoparticles.