Senate consideration of unratified treaties to limit nuclear testing.

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Trait physiology and crop modelling as a framework to link phenotypic complexity to underlying genetic systems

New tools derived from advances in molecular biology have not been widely adopted in plant breeding for complex traits because of the inability to connect information at gene level to the phenotype in a manner that is useful for selection. In this study, we explored whether physiological dissection and integrative modelling of complex traits could link phenotype complexity to underlying genetic systems in a way that enhanced the power of molecular breeding strategies. A crop and breeding system simulation study on sorghum, which involved variation in 4 key adaptive traits-phenology, osmotic adjustment, transpiration efficiency, stay-green-and a broad range of production environments in north-eastern Australia, was used. The full matrix of simulated phenotypes, which consisted of 547 location-season combinations and 4235 genotypic expression states, was analysed for genetic and environmental effects. The analysis was conducted in stages assuming gradually increased understanding of gene-to-phenotype relationships, which would arise from physiological dissection and modelling. It was found that environmental characterisation and physiological knowledge helped to explain and unravel gene and environment context dependencies in the data. Based on the analyses of gene effects, a range of marker-assisted selection breeding strategies was simulated. It was shown that the inclusion of knowledge resulting from trait physiology and modelling generated an enhanced rate of yield advance over cycles of selection. This occurred because the knowledge associated with component trait physiology and extrapolation to the target population of environments by modelling removed confounding effects associated with environment and gene context dependencies for the markers used. Developing and implementing this gene-to-phenotype capability in crop improvement requires enhanced attention to phenotyping, ecophysiological modelling, and validation studies to test the stability of candidate genetic regions.

Predictive genetic test decisions for Huntington's disease: Elucidating the test/no-test dichotomy

Predictive genetic testing for serious, mature-onset genetic illness represents a unique context in health decision making. This article presents findings from an exploratory qualitative Australian-based study into the decision making of individuals at risk for Huntington's disease (HD) with regard to predictive genetic testing. Sixteen in-depth interviews were conducted with a range of at-risk individuals. Data analysis revealed four discrete decision-making positions rather than a 'to test' or not to test' dichotomy. A conceptual dimension of (non-)openness and (non-)engagement characterized the various decisions. Processes of decision making and a concept of 'test readiness' were identified. Findings from this research, while not generalizable, are discussed in relation to theoretical frameworks and stage models of health decision making, as well as possible clinical implications.

Vaccine components and constituents: Responding to consumer concerns

Vaccination remains a vital strategy in the prevention of infectious disease. Commercial vaccine formulations contain a range of additives or manufacturing residuals, which may contribute to patient concerns about vaccine safety. Primary health care professionals are well placed to address patient concerns about vaccine safety. We describe the key constituents present in vaccines, discuss issues related to safety and acceptability of these constituents, and provide a table highlighting constituents of commercially available vaccines in Australia.

Trait physiology and crop modelling to link phenotypic complexity to underlying genetic systems

New tools derived from advances in molecular biology have not been widely adopted in plant breeding because of the inability to connect information at gene level to the phenotype in a manner that is useful for selection. We explore whether a crop growth and development modelling framework can link phenotype complexity to underlying genetic systems in a way that strengthens molecular breeding strategies. We use gene-to-phenotype simulation studies on sorghum to consider the value to marker-assisted selection of intrinsically stable QTLs that might be generated by physiological dissection of complex traits. The consequences on grain yield of genetic variation in four key adaptive traits – phenology, osmotic adjustment, transpiration efficiency, and staygreen – were simulated for a diverse set of environments by placing the known extent of genetic variation in the context of the physiological determinants framework of a crop growth and development model. It was assumed that the three to five genes associated with each trait, had two alleles per locus acting in an additive manner. The effects on average simulated yield, generated by differing combinations of positive alleles for the traits incorporated, varied with environment type. The full matrix of simulated phenotypes, which consisted of 547 location-season combinations and 4235 genotypic expression states, was analysed for genetic and environmental effects. The analysis was conducted in stages with gradually increased understanding of gene-to-phenotype relationships, which would arise from physiological dissection and modelling. It was found that environmental characterisation and physiological knowledge helped to explain and unravel gene and environment context dependencies. We simulated a marker-assisted selection (MAS) breeding strategy based on the analyses of gene effects. When marker scores were allocated based on the contribution of gene effects to yield in a single environment, there was a wide divergence in rate of yield gain over all environments with breeding cycle depending on the environment chosen for the QTL analysis. It was suggested that knowledge resulting from trait physiology and modelling would overcome this dependency by identifying stable QTLs. The improved predictive power would increase the utility of the QTLs in MAS. Developing and implementing this gene-to-phenotype capability in crop improvement requires enhanced attention to phenotyping, ecophysiological modelling, and validation studies to test the stability of candidate QTLs.

Application of digital image processing techniques to the photometric testing of vehicle headlamps

The aim of this Interdisciplinary Higher Degrees project was the development of a high-speed method of photometrically testing vehicle headlamps, based on the use of image processing techniques, for Lucas Electrical Limited. Photometric testing involves measuring the illuminance produced by a lamp at certain points in its beam distribution. Headlamp performance is best represented by an iso-lux diagram, showing illuminance contours, produced from a two-dimensional array of data. Conventionally, the tens of thousands of measurements required are made using a single stationary photodetector and a two-dimensional mechanical scanning system which enables a lamp's horizontal and vertical orientation relative to the photodetector to be changed. Even using motorised scanning and computerised data-logging, the data acquisition time for a typical iso-lux test is about twenty minutes. A detailed study was made of the concept of using a video camera and a digital image processing system to scan and measure a lamp's beam without the need for the time-consuming mechanical movement. Although the concept was shown to be theoretically feasible, and a prototype system designed, it could not be implemented because of the technical limitations of commercially-available equipment. An alternative high-speed approach was developed, however, and a second prototype syqtem designed. The proposed arrangement again uses an image processing system, but in conjunction with a one-dimensional array of photodetectors and a one-dimensional mechanical scanning system in place of a video camera. This system can be implemented using commercially-available equipment and, although not entirely eliminating the need for mechanical movement, greatly reduces the amount required, resulting in a predicted data acquisiton time of about twenty seconds for a typical iso-lux test. As a consequence of the work undertaken, the company initiated an 80,000 programme to implement the system proposed by the author.

Why do firms invest in consumer advertising with limited sales response? A shareholder perspective

Marketing managers increasingly recognize the need to measure and communicate the impact of their actions on shareholder returns. This study focuses on the shareholder value effects of pharmaceutical direct-to-consumer advertising (DTCA) and direct-to-physician (DTP) marketing efforts. Although DTCA has moderate effects on brand sales and market share, companies invest vast amounts of money in it. Relying on Kalman filtering, the authors develop a methodology to assess the effects from DTCA and DTP on three components of shareholder value: stock return, systematic risk, and idiosyncratic risk. Investors value DTCA positively because it leads to higher stock returns and lower systematic risk. Furthermore, DTCA increases idiosyncratic risk, which does not affect investors who maintain well-diversified portfolios. In contrast, DTP marketing has modest positive effects on stock returns and idiosyncratic risk. The outcomes indicate that evaluations of marketing expenditures should include a consideration of the effects of marketing on multiple stakeholders, not just the sales effects on consumers.

Relationship fading in business-to-consumer context

The objective of this paper is to explain the phenomenon of relationship fading in a business-to-consumer (B2C) context and to identify the key antecedents and drivers in this process. Fading relates to a gradual decline in consumers’ willingness to continue a relationship with a company. Therefore it may help to elucidate the ‘unexplained’ relationship dissolution and customer defection. Led by an assumption that a relationship between a consumer and a brand is like the one between individuals, the paper proposes that the trajectory of relationship fading reflects disaffection processes similar to the ones suggested in marital and romantic relationships between individuals. Stages of the fading process and their characteristics are presented. Academic and practical implications are subsequently presented.

Relationship fading in business-to-consumer context

The objective of this thesis is to develop a better understanding of the relationship fading phenomenon in business-to-consumer context. Fading relates to a gradual decline in consumer’s willingness to continue a relationship with a company. Therefore, understanding the fading process may help to elucidate the ‘unexplained’ relationship dissolution and customer defection. Led by an assumption that a relationship between a consumer and a brand is like the one between individuals, the thesis proposes that the trajectory of relationship fading reflects the disaffection processes similar to the ones suggested in marital and romantic relationships between individuals. The approach taken to answering this research question is a multi-study approach. This type of approach allows addressing each individual research question independently, using the most appropriate research methods. As a result, the thesis comprises three adjacent studies. All three studies are linked and together contribute to a better understanding of the relationship fading process, which is the main topic of the thesis. Based on the results from the first study, a set of boundary conditions of relationship fading is identified. The results of the second study suggest that predictors of relationship fading stage can be uncovered. Thirdly, different restoration techniques are explored, aiming to describe their effectiveness in various relationship fading stages. Individual objectives of the three studies are accomplished. All three studies contribute to achieving the overall objective of the thesis, namely to developing a better understanding of the phenomenon of relationship fading.

Investigating an Alternative Treatment to Cystic Fibrosis: Testing the Effect of Panax ginseng C.A. Meyer extracts on Pseudomonas aeruginosa

The predominant pathogen found in the lungs of cystic fibrosis (CF) patients is Pseudomonas aeruginosa. The success of the infection is partially due to virulence factor production, which is regulated by quorum sensing (QS) signaling. Currently, antibiotics are used to treat the infection, but resistant forms of P. aeruginosa have evolved, necessitating alternative treatments. Previous animal studies showed that treatment with extracts from the Chinese herb Panax ginseng C.A. Meyer reduced bacterial load resulting in a favorable immune response. It is hypothesized that ginsenosides, the major bioactive compounds in ginseng, is responsible for this effect. This study explores the role of ginseng extracts in attenuating P. aeruginosa virulence. A sequential extraction was performed using hexane, methylene chloride, methanol, and water. High performance liquid chromatography (HPLC) analysis showed the methanol and water ginseng extracts contained the known ginsenosides Rb1, Rb2, Rc, Rd, Re, and Rg1• All extracts were tested on biomonitor strains of Agrobacterium tumefaciens,Chromobacterium violaceum, and P. aeruginosa. Antibacterial and anti-QS activity were assessed using a disc diffusion assay. This was then followed by thin layer chromatography (TLC) bioautographic assay to further separate active compounds. The hexane and dichloromethane extracts, that lacked ginsenosides, displayed antibacterial activity against C. violaceum, whereas methanol and water extracts had anti-QS activity. The results of the bioassay with the pure ginsenoside standards showed that they lack antibacterial or anti-QS activity. Our results indicate that there are bioactive compounds, other than ginsenosides, that are the cause of antibacterial effects and anti-QS in the ginseng extracts.