Chromatographic profiling and multivariate analysis for screening and quantifying the contributions from individual components to the bioactive signature in natural products

A new approach for assigning bioactivity to individual components in extracts from natural products is presented and validated. 60 mixtures were created according to a uniform design from 12 chemical components of which 7 possessed antioxidant activity. The synthetic mixtures were characterized by chromatographic profiling and their antioxidant power was assessed by use of the Ferric Reducing Antioxidant Power (FRAP) assay. 40 of the prepared mixtures were used as a training set to create a cross validated partial least squares (PLS) regression model with the FRAP measurement as response. The remaining 20 mixtures were used as an independent external validation set. The bioactive signature was singled out from the multi-component PLS model using target projection (TP). In addition to excellent prediction performance of antioxidant strength from the bioactive signature, our approach, called Quantitative Pattern-Activity Relationship (QPAR), was able to rank 6 of the 7 bioactive components according to individual bioactive strength. The ratios of bioactive capacity of the two most active components to the two least active components were close to 100 to 1. This explains why one of the two least bioactive components was not detected

South East Queensland Gay Community Periodic Survey: June 1998

Gay Community Periodic Surveys surveys are regularly conducted in Sydney, Melbourne, Brisbane, Cairns, Canberra, Adelaide and Perth to monitor changes in sexual and other risk practices over time among Australian gay men who are gay community attached, recruited from gay sex-on-premises venues, social sites and clinics

Queensland Gay Community Periodic Survey: June 1999

The Queensland Gay Community Periodic Survey is an annual cross-sectional survey of gay and homosexually active men recruited through a range of sites in Brisbane, the Gold Coast and the Sunshine Coast, and Cairns. The project was funded by Queensland Health. The Periodic Survey provides an annual snapshot of sexual and HJV-related practices among gay and homosexually active men.The major aim of the Queensland Periodic Survey is to provide data on levels of safe and unsafe sexual practice in a broad cross-sectional sample of gay and homosexually active men. To this end, men were recruited from a number of gay-community venues and sexual health clinics

An investigation into international postgraduate students’ decision-making process

This paper analyses the student decision-making model for international postgraduate (PG) students with a concentration on consumer service marketing principles. Using a grounded theory approach and exploratory techniques (focus groups), it investigates qualitatively why the UK is the destination choice, the rationale for the programme of study and the feelings of these students as they have progressed throughout the whole of the service consumption period. The longitudinal study incorporated focus groups with a sample size of 35 MBA students with each participant contributing four times over an eighteen months period and seven sets of focus groups were held making a total of 28 focus group sessions. Results found that uncertainty and shock in the initial periods were followed by more positive experiences later in the consumption process. Being a PG student can be challenging as tutors presume there is a prior awareness of the UK Higher Education learning environment and this was certainly not the case. Consequently students had felt intimidated earlier on but as the consumption process progressed and they started to experience their modules and learn, their confidence grew, because they had found their voice

Genomics in marine monitoring: New opportunities for assessing marine health status

This viewpoint paper explores the potential of genomics technology to provide accurate, rapid, and cost efficient observations of the marine environment. The use of such approaches in next generation marine monitoring programs will help achieve the goals of marine legislation implemented world-wide. Genomic methods can yield faster results from monitoring, easier and more reliable taxonomic identification, as well as quicker and better assessment of the environmental status of marine waters. A summary of genomic methods that are ready or show high potential for integration into existing monitoring programs is provided (e.g. qPCR, SNP based methods, DNA barcoding, microarrays, metagenetics, metagenomics, transcriptomics). These approaches are mapped to existing indicators and descriptors and a series of case studies is presented to assess the cost and added value of these molecular techniques in comparison with traditional monitoring systems. Finally, guidelines and recommendations are suggested for how such methods can enter marine monitoring programs in a standardized manner