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Over the last 20 years there have been dramatic advancements in our understanding of language; particularly regarding the ontogeny, phylogeny and neurobiology of syntactic abilities. Yet, how these language processes evolved remains unclear. The ability to extract information about the regularities present in sequentially presented stimuli has been related to both the acquisition and use of natural syntax. As a result, structured sequence learning is considered to be one of the general cognitive abilities from which language could have evolved. If sequence learning does represent an early precursor to human syntactic processing, there should be evidence of comparable sequence learning abilities in other primates with whom humans share a common ancestor. To this end, this thesis explores the sequence learning abilities of humans, and their evolutionary relatives, the macaque. Artificial grammars (AG) were used to create sequences that emulate some of the order-based relationships found between words in a sentence. The first study used a nonadjacent AG where the first syllable in a triplet is predicted the third syllable. Electroencephalography (EEG) was used to show that the macaque brain potentials elicited by a violation to the nonadjacent relationships were more similar to those previously found in infants, than adults tested on the same paradigm. Together the results indicated that both infants and macaques extracted the sequencing relationships more automatically than adults who have already acquired language. The subsequent studies tested how humans and macaques respond to identically structured sequences of either auditor)’ or visual stimuli. Behavioural results showed that sequence learning in both humans and macaques occurs in a very similar manner across the modalities. Subsequent imaging work also found correspondences across the two species, finding that similar frontal and parietal regions were associate with both auditory’ and visual sequence learning. Although, results in the macaque are preliminary and presented as a case study. Together, the studies provide evidence that human sequencing abilities stem from an evolutionary’ conserved capacity to extract regularities from sequentially presented stimuli and that this process is similarly represented in both humans and macaques.

Calcium Dependent Antibiotic (CDA), is a nonribosomal lipopeptide antibiotic from Streptomyces coelicolor. It is an undecapeptide with an unusual N-terminal 2,3-epoxyhexanoyl fatty acid side chain. It contains many nonproteinogenic amino acids such as D-4-hydroxyphenylglycine, D-3-phosphohydroxyasparagien, L-3-methylglutamic acid and Z-2,3-dehydrotryptophan. CDA is very similar in structure to the antibiotic daptomycin, which under the trade name Cubicin has recently been approved for the treatment of skin infections. The work described in this thesis focuses on a number of different areas, with the overall aim of delineating the biosynthetic origin of CDA and investigating the possibility of producing modified cyclic lipopeptides through a combined chemical and biochemical approach. Strategies used in engineering the biosynthesis of CDA may then be applied to other related, nonribosomal peptides of therapeutic importance, in order to improve their biological activity.

In this study, data collected in a survey of Scottish sheep farmers was used to corroborate and augment secondary data available in the literature on sheep ectoparasites and their control in 1999/2000.  The data was used to design and construct a decision tree model, which was used to determine probability weighted profit-maximising control strategies for six flock types/size groups that were representative of Scottish sheep farms.  Organophosphate (OP) based dips, applied in both the autumn and spring/summer, were found to be the profit-maximising control strategy for five flock types/size groups.  The exception was for small (100-ewe) lowground flocks, where two applications of cypermethrin in pour-on formulation maximised the avoidable disease losses. Each of these strategies can give rise to animal welfare, human health and /or environmental externalities.  OP dips can damage human health and the environment but minimise animal welfare losses, and cypermethrin pour-on, while non-damaging to human health and the environment, can result in some avoidable welfare losses, as ectoparasite control is less effective than for OP dips. Using multi-criteria analysis (MCA), the economics of sheep ectoparasite control from a social standpoint has also been examined.  Some profit-maximising control strategies do not necessary maximise social benefits.  A conflict can arise between the farmer and society.  The minimum cost that society would need to be willing to accept in order to finance possible incentives for sheep farmers to switch from the profit-maximising control strategy to strategies that provide different bundles of social benefits is estimated.