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A puzzle is generated by two intuitions about artworks: 1. There is no prima facie reason to take artworks to be mind-independent objects; 2. Aesthetic judgments are objective. These intuitions seem to be in tension, for if artworks or their aesthetic properties are mind-dependent, how can aesthetic judgments be objective? The common solution to the puzzle lies in rejecting or revising one of the two intuitions. Typically, realists reject 1, and many antirealists reject 2. I develop an antirealist aesthetic theory that accommodates both intuitions, focusing on critical disagreement between epistemically optimal judges, realist difficulties with supervenience and response-dependence, the role of imagination in the experience of artworks, and the metaphorical quality of aesthetic discourse. The hallmark of realism, namely the mind-independence of aesthetic qualities, is an untenable commitment that yields an impoverished view of artworks. A cognitivist anti-realism is available which preserves the objectivity of aesthetic discourse and yields a richer conception of artworks and our interaction with them.

The standard paradigm of active galactic nuclei (AGN) postulates that their luminosity, L ~ 1039−48erg s−1, derives from the accretion of gas onto a supermassive black hole, mass M ~ 106−9M☉, at the centre of a host galaxy. Echo or reverberation mapping affords a method of relating flux variations at different wavelengths to determine the nature of the flux emitting regions, with μ-arcsecond resolution. The results of an intensive two-month campaign of ground based spectrophotometric monitoring of the Seyfert 1 galaxy NGC 7469, with a temporal resolution of ≤1 day, are presented. Application of echo mapping techniques reveal the virial mass of the central source to be MNGC 7469 ~106−7 M☉, and a compact broad Balmer line emitting region ~ 5 light days from the central source. Together, this evidence suggests the existence of a supermassive black hole in NGC 7469. Further, evidence for significant wavelength- dependent continuum time delays is presented, with optical continuum variations lagging those at UV wavelengths by about 1-2 days. The wavelength-dependent time delays, (λ), are consistent with the predicted T ∝ λ 4/ 3 relationship for an irradiated blackbody accretion disc with temperature structure T(R) ∝ R−3/4 and hence may represent the indirect detection of an accretion disc structure in NGC 7469. It is shown that wavelength-dependent time delays test the standard black-hole accretion disc paradigm of AGN, by measuring T(R) of the gaseous material surrounding the purported black hole. Moreover, a new direct method is presented that combines observed time delays and the spectral energy distribution of an AGN to derive a redshift-independent luminosity distance; assuming the observed time delays are indeed due to a classical accretion disc structure. The luminosity distance permits an estimate of the Hubble constant, H0-the expansion rate of the Universe. The first application of the method yields H0(cos i/0.7)1/2 = 38 ± 7km s−1 Mp −1. A more accurate determination of H0 requires either an independent accurate determination of the disc inclination i or statistical average of a moderate sample of active galaxies. This method permits determination of redshift-independent luminosity distances to AGNs, thereby, giving a new route to H0, and by extension to fainter objects at z ~ 1, q0.

1. Physiological experiments were devised to study the electrical responses of ochinoderm muscle during contraction. The smooth muscle forming the lantern retractors of Eching conducts spike potentials at a speed off 4 cms. A sec. 2. Three muscle systems examined with the electron microscope reveal a layout that varies in complexity. The muscle cells give rise to processes that are synapsed upon by nerves. 3. The area containing the ribbon axons described by Smith (1950) was examined and the ribbon axons shown to be selectively stained muscle cells. 4. In the three muscle systems examined controlling ganglion was found to be associated sytams. 5. The ganglia contained large numbers of structures that are described as synapses. These synapses are of a simple type and do not possess the specialisations that are present in the synapses of some other invertebrate phyla. 6. The sensory cells of the epithalium are described and an examination has indicated that the cells of the general epithelial are all sensory and contribute axons to the nerve plexus. Some of these epithalial cells are modified into probable chemoreceptors, light receptors and are found in statocysts. 7. A hypothesis to account for the co-ordination of the behaviour of echinoderms in propounded.

Cells of ataxia telangiectasia (AT) individuals are hypersensitive to a variety of DNA damaging agents such as ionizing radiation and bleomycin, presumed to be due to an intrinsic defect in repair of DNA damage. The nature of the DNA lesion(s) to which AT cells are abnormally sensitive, and the defect in DNA repair are presently unclear. The major part of this project aimed at investigating the sensitivity of AT cells to DNA double-strand breaks (dsb) generated by restriction endonucleases (RE), thereby verifying the hypothesis that AT cells are deficient in the processing of dsb. AT lymphoblastoid cell lines (AT-PA and AT-KM) used in this study were initially characterized and found to be approximately 3 times more sensitive to ionizing radiation in the induction of micronuclei (Mn) and chromosomal aberrations (CA) compared with a normal lymphoblastoid cell line (N-SW). Other cellular characteristics were observed in AT-PA cells following-irradiation such as normal induction and rejoining of dsb and reduced inhibition of DNA synthesis. By using SLO poration, RE were introduced into the AT and normal cell lines and the yield of CA resulting from RE-induced dsb were subsequently investigated. The frequencies of CA induced by Pvu II were 2 - 4 fold higher in AT-PA than in N-SW cells at both 5 h and 24 h sampling times. The enhanced frequency of CA in AT cells treated with Pvu II was principally a result of an increase of chromatid aberrations, rather than chromosome aberrations at 24 h. higher frequencies of chromatid exchanges appeared in AT-PA than in N-SW cells. The results suggest that AT cells are characterized by a defect in dsb processing that converts a higher number of dsb into CA than in the normal cell line. With respect to the different end-structures of RE-induced dsb, cohesive-ended dsb generated by BamH I and Pst I were found to induce lower frequencies of CA than blunt-ended dsb generated by Pvu II and EcoR V in both the AT cell lines and the normal cell line. The results support the previous observations that cohesive-ended dsb are less clastogenic than blunt-ended dsb (Bryant 1984). Although inducing lower frequencies of CA than Pvu II and EcoR V, BamH I and Pst I induced higher number of CA in both AT-PA and AT-KM cells when compared with N-SW cells, again indicating a defect in processing cohesive-ended dsb exists in AT cells. A potent DNA repair inhibitor, Ara A, was found to potentiate the production of CA by RE in AT and normal cells. The enhancement ratios (by ara A) for CA induced by Pvu II and Pst 1 were higher in N-SW cells than in AT-PA and AT-KM cells. Ara A appeared to have no effect on the frequencies of CA induced by BamH I in any of the cell lines tested. Based on these findings, a mechanism for the rejoining of RE-induced dsb in which DNA repair synthesis may be involved is proposed, and it is postulated that dsb in AT cells are subjected to greater end degradation. Inhibition of DNA synthesis was observed in normal cells after treatment with Pvu II and EcoR V, while EcoR I and BamH I had only minor effect. AT-PA cells were found to be resistant to RE-induced inhibition of DNA synthesis, as in the case of ionizing radiation. This result suggests that RE-induced blunt-ended dsb mimic radiation-induced lesions in supressing DNA synthesis in normal cells and that AT cells respond to RE-induced dsb in a similar way to damage induced by ionizing radiation. Finally, when a nuclear extract from N-SW cells was introduced into Pvu Il-treated AT-PA cells, it was able to confer a normal frequency of CA. In contrast, neither whole cell nor nuclear extracts from normal cells influenced the production of CA induced by y-rays. These findings provide evidence for the presence of factor(s) in normal nuclear extract which complements the defect in processing of RE-induced dsb in AT cells.

A series of P4 (Cbz and t-Boc) N-protected potential substrates and inhibitors, containing the P1 to P4 substrate recognition sequence of the type 2 adenovirus proteinase (Leu-Ala-Gly-Gly) were prepared by solution phase peptide coupling techniques and tested for activity against the proteinase. The potential substrates contained the amide and ester moieties at the P1 carbonyl position and the potential inhibitors contained the alcohol, acid, bromide, aldehyde, ketone, dimethylacetal, nitrile, alkenic, malonyl and epoxysuccinate moieties at the P1 carbonyl position. The esters, the t-Boc urethane and the p-nitroanilide moieties were substrates for the proteinase and the acid and the amides did not bind to the proteinase. Preliminary results show that the other inhibitors were mostly noncompetitive inhibitors for the adenovirus proteinase with approximate Ki's between 15 and 200 μmol dm-3. The test results indicate that the amides must contain a carbonyl group at P2' to bind to the proteinase; the loss of the P1' amine product is the rate limiting step for the hydrolysis of a substrate by the adenovirus proteinase; the P acid product leaves before the P' amine product, which is in complete contrast to classical cysteine proteinases such as papain; little protonation of the P1'amide nitrogen or the P1 carbonyl oxygen of the adenovirus proteinase-substrate complex occurs before the nucleophilic attack on the P1 carbonyl carbon of the adenovirus proteinase-substrate complex.

Chapter 1 General Introduction: The general introduction initially presents the major landmarks in muscle research of the last 3 millennia. The proteins of the contractile apparatus and their role in muscle contraction are described. There is then a description of how contractile proteins are known to alter through the expression of isoforms. Finally, a description of fish muscle and its fibre types is given, followed by the aims of the thesis. Chapter 2 Materials and Methods: An account is given of the materials and methods used throughout this thesis. This includes myofibril preparation and electrophoretic techniques. The techniques described are one and two dimensional polyacrylamide gel electrophoresis (PAGE), iso-electric focusing (lEF), peptide mapping, and one and two dimensional alkali-urea PAGE. The methods used to fix, stain and store the gels are then given, followed by the protocol used for Western blotting. Finally, the analysis of proteins bands is described. Chapter 3 Temperature and the plasticity of myofibrillar proteins during ontogeny in the Atlantic herring (Clupea harengus L.): Many aspects of development are influenced by temperature. The aim of this study was to investigate the effect of rearing temperature on the development and myofibrillar protein expression during ontogeny in the Atlantic herring (Clupea harengus L.). Chapter 4 The effect of body size on the myofibrillar protein composition of fast muscle fibres in the short horn sculpin (Myoxocephalus scorpius L.): The contractile properties of muscle vary with body length in fish. The aim of this study was determine if the proteins altered with body size in the short-horn sculpin (Myoxocephalus scorpius L.). Furthermore, could changes in protein expression be related to differences in contractile properties. Chapter 5 The myofibrillar proteins of Antarctic and sub-Antarctic fish: The myosins of Antarctic fish are specialised for function at low temperature. The aim of this study was to determine if the myofibrillar proteins present in Antarctic fish were highly conserved for function in this stable, low temperature environment. The variation in protein structure from myotomal fast muscles and the m. adductor profundis between five Antarctic fish species from two genera was compared with five sub-Antarctic species from four genera. The myofibrillar proteins of both the Antarctic and sub-Antarctic species showed a high degree of similarity between fish within the same genera. However, the isoforms present were considerably different between genera in both the Antarctic and sub-Antarctic species. Furthermore, the extent of the variation in protein isoforms between genera of the Antarctic fish was similar to that of the sub-Antarctic fish. This suggests that divergence in the tertiary structure of myosins from these species has occurred and that the Antarctic fish myofibrillar proteins are not highly conserved. Chapter 6 General Discussion: The major findings of the thesis are discussed in relation to the expression of myofibrillar proteins, with reference to further studies.

The thesis argues that human work is a transformative activity which essentially consists of three dynamically interrelated dimensions: the instrumental, relational, and ontological dimensions. By these, along with work being an end in itself, the worker's and others' needs are providentially met; believers' sanctification is occasioned; and workers express, explore and develop their humanness while building up their natural, social and cultural environments to both protect and produce the order of this world and of the one to come. The first part shows that past and present theological evaluations of work are best understood according to this threefold description. Work's threefold nature is shown to correspond with Scripture (although here the instrumental is mainly discussed); the Patristic understanding opens up reflection toward work's ontology; and the Reformation particularly develops further the relational and ontological dimensions. In the modern Roman Catholic understanding, work's threefold nature does appear, although as seen in Laborem Exercens, the relational is given hierarchical priority over the instrumental. As modern Protestants revise old and explore new approaches, work's threefold understanding also emerges. However, the dimensions need further interrelated development, and the ontological needs to be more adequately expounded. The second part of the thesis develops work's ontology. A teleological framework is first established in dialogue with Alasdair MacIntyre and Oliver O'Donovan showing that eschatological and protological purposes and ends are essential for understanding a thing's nature (constitutionally and ethically). This builds toward a theological anthropology where an interpretive survey and interaction with Colin Gunton's anthropology highlights the necessity of relational and functional concepts. The ontology of work is further developed in dialogue with Jürgen Moltmann's anthropology. Work is shown to be a fundamental facet of created human existence, initially a part of God's creation, and in the resurrection a fundamental part of God's coming new creation. Finally, the overall proposal, a definition of work, redraws the boundaries for a theology of work, and functions as a dynamic model for ethically evaluating work.

It is the purpose of this thesis to examine the reasons why Cuzco Quechua, an Amerindian language of Latin America, uses allomorphs, or multiple forms, to represent the minimal semantic units of the language (or morphemes). Starting from the Initial hypothesis that the relatively minor role of allomorphy in contemporary Cuzco Quechua indicates the earlier absence of that allomorphy, the motivation for the introduction and retention of allomorphy is examined, as this relates to a number of characteristic types; Vowel Deletion, affecting final suffixes, Consonant Cluster Simplification and Vowel Dissimilation, affecting suffixes of the verb stem, and the potential allomorphy of the suffixes of Person, pronominal and verbal. Such allomorphy proves to be the result of attempts to contain new morphological developments within existing structural preferences of syllable configuration, and to limit the potential for semantic ambiguity, arising out of identity of form, or homonymy. The unanticipated result of such a study is the implication in all cases considered of an earlier process of affixation, leading to the formation of untypical morph-forms, Allomorphy is seen to be the by-product of compensatory change, introduced to modify the results of previous developments, In particular, the role of the 'empty morph', ni, of nominal Person is found to be implicated in the derivational history of all Quechua suffixes of Person, and its origin imputed to an early role of the verb ni-, 'to say', used with auxiliary function. Based on the evidence of allomorphy, the conclusion is drawn that many of the suffixes of Cuzco Quechua owe their origin to syntactic forms of expression, indicating that the role of the syntactic construction in this typically agglutinative language was formerly more significant than is now recognised.

The thesis addresses the issues of error through misidentification and immunity to error through misidentification in relation to the problem of the first person. First, it provides an explanation of error through misidentification. Secondly, it shows that there are two possible ways of understanding immunity to error through misidentification. It is then argued that the first understanding of immunity to error through misidentification leads to what is labelled "the trilemma about the self". That is to say, either we provide an explanation of immunity to error through misidentification, but we subscribe to two contentious metaphysical views about the self-the Cartesian and the Idealist; or else we hold the view that the self is identical with a human being, but we have no explanation of immunity to error through misidentification. It is then shown that in order to solve the trilemma, a different understanding of immunity to error through misidentification must be offered. After discussing various possible understandings of immunity to error through misidentification, a sound account of it is finally provided. Moreover, it is shown how non-inferential, introspection-based mental self-ascriptions can comply with it, in such a way that they turn out to be logically immune to error through misidentification. Finally, by drawing on Evans' and Peacocke's accounts of the possession conditions of the first person concept-in which IEM I-judgements play a central role-, it is shown that it is a concept of a human being who thinks of herself as such. Hence, our first person concept is firmly anti-Cartesian and anti-Idealist. As a consequence, it is maintained that not only is there no need to hold the Cartesian and the Idealist metaphysics of the self in order to explain why some I-judgements can be immune to error through misidentification, but it is also argued that one can no longer be either Cartesian or Idealist. For that would expose one to conceptual incoherence.