Expertise in topographic map reading is dependent on efficient processing of geographical information presented in a standardised map format. Studies have supported the proposition that expert map readers employ cognitive schemas in which prototypical configurations held in long term memory are employed during the surface search of map features to facilitate map comprehension. Within the experts' cognitive schemas, it is assumed that features are grouped according to spatial configurations that have been frequently encountered and these patterns facilitate efficient chunking of features during information processing. This thesis investigates the nature of information held in experts' cognitive schemas. It also proposes that features are grouped in the experts' schemas not only by their spatial configurations but according to the abstract and functional roles they perform. Three experiments investigated the information processing strategies employed by firstly, skilled map readers engaged in a map reproduction task and secondly, expert map readers engaged in a location comparison exercise. In the first and second experiments, skilled and novice map readers studied and reproduced a town map and a topographic map. Drawing protocols and verbal protocols provided insights into their information processing strategies. The skilled map readers demonstrated superior performance for reproducing contour related data with evidence of the use of cognitive schemas. For the third experiment, expert and novice map readers compared locations within map excerpts for similarities of boundary extents. Eye-gaze data and verbal protocols provided information on the features attended to and the participants' search patterns. The expert group integrated features into their cognitive schemas according to the abstract roles they performed significantly more frequently than the novices. Both groups employed pattern recognition to integrate features for some of the locations. Within a similar experimental design the second part of the third experiment examined whether experts also integrated the abstract roles of remote features and village grouping concepts within their cognitive schemas. The experts again integrated the abstract roles of physical features into their schemas more often than novices but this strategy was not employed for either the remote feature or grouping categories. Implications for map design and future Geographic Information Systems are discussed.

Abstract Gibberellins (GAs) are a class of plant hormones that regulate many aspects of plant growth and development including seed germination, stem elongation and fruit development. To investigate the regulation of GA biosynthesis and the impact of altered GA levels on plant growth and development, transgenic pea (Pisum sativum L. cv. Carneval) plants were generated to overexpress PsGA3ox1 (codes for GA 3-hydroxylase which converts GA20 to bioactive GA1) under the control of the CaMV-35S promoter. Increased expression of the transgene PsGA3ox1 was correlated with altered plant phenotype including longer internodes, larger stipules and tendrils, and longer pods. Transgenic lines also showed upregulation of the GA catabolic genes PsGA2ox1 and/or PsGA2ox2, suggesting that GA1 substrate-induced feedback regulation also occurs to maintain GA homeostasis. Changes in endogenous GAs, quantified using an isotope dilution method, indicated that an increased flux in GA biosynthesis occurred in the expanding internodes, stipules and tendrils of the PsGA3ox1-overexpressor lines. Higher bioactive GA1 levels and growth were correlated with lower PsGA2ox1 transcript levels in elongating internodes, and oscillation of these parameters between adjacent elongating internodes in the PsGA3ox1-overexpression lines suggests that coordination of bioactive GA levels and growth occurs between adjacent internodes. During germination and early seedling growth, GA gene expression studies suggested that PsGA3ox1-overexpression increased the flux through to bioactive GA in the cotyledons, shoots and roots of pea seedlings, resulting in longer shoots but shorter roots. Auxins are a class of plant hormones involved in growth and differentiation of plants that can influence GA biosynthesis and action. The location and action of auxins is in part regulated by auxin carrier proteins. The expression patterns of the putative auxin efflux carrier genes PsPIN1 and PsPIN2 in elongating internodes were correlated with vascular re-patterning events in this tissue, and PsGA3ox1-overexpression appears to increase internode PsPIN1 and PsPIN2 transcript abundance and the formation of the vascular connections between the internode and the axillary buds. Overall, characterization of PsGA3ox1-overexpressor lines in pea demonstrated that bioactive GA levels are tightly regulated in pea tissues for the coordination of plant growth and development. / Plant Science

The multiplex PCR experiment is to amplify multiple regions of a DNA sequence at the same time by using different primer pairs. Although, in recent years, there are lots of methods for PCR primer design, only a few of them focus on the multiplex PCR primer design. The multiplex PCR primer design is a tedious task since there are too many constraints to be satisfied. A new method for multiplex PCR primer design strategy using genetic algorithm is proposed. The proposed algorithm is able to find a set of suitable primer pairs more efficient and uses a MAP model to speed up the examination of the specificity constraint. The dry-dock experiment shows that the proposed algorithm finds several sets of primer pairs for multiplex PCR that not only obey the design properties, but also have specificity.

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