The application of the discrete Fourier transform to the determination of the frequency content of unevenly-sampled astronomical time series is discussed, and an interactive computer package which incorporates a variety of power-spectrum and time-domain techniques is described. A frequency analysis of the light curves of two hot, extreme helium stars, BD-9°4395 and HD160641, shows that their photometric variability is caused by non-radial pulsation. Spectroscopic evidence in support of non-uniform mass loss is presented for BD-9°4395. Spectroscopic and photometric observations of two early-type eclipsing binary systems, AL Sculptoris and DM Persei, have been analysed to yield their absolute dimensions. AL Scl is found to be a detached system in which both components rotate faster than synchronism. The origin of distortions in its light curve is unclear. DH Per is shown to be part of a triple system in which the third component is most probably a late-B star in a 98-day orbit with a semi-major axis of 0.9 A.U. The binary system is confirmed to be semi-detached and to have evolved through a phase of rapid mass transfer. DH Per joins a small group of massive, semi-detached systems whose characteristics differ significantly from the classical Algols, and which may result from case-A, mass-transfer processes. Spectroscopic and photometric observations of the F4V star HD123058 do not support the hypothesis that it is a binary system. Broad lines in its spectrum are attributed to a somewhat enhanced rotation rate, and the star is shown to be essentially unevolved. The derivation of the equation of condition in Sterne's rigorous method for the analysis of the spectroscopic elements of binary systems, and its modification for incorporating observed times of minimum light into the adjustment of the elements, are outlined. A computer code for the determination of orbital elements according to this scheme is described.

No description available.

This study assesses the suitability of four sectional shear methods for predicting the shear capacity of reinforced concrete members which do not comply with S6-06 Section 14 stirrup spacing and area requirements. The results of the evaluations indicate that the sectional shear provisions in S6-06, AASHTO LRFD-05 and software Response 2000 appropriately account for variations in stirrup spacing and area detailing, and present with good agreement between predicted and tested shear capacities for member with deficient shear reinforcement. However, shear capacities calculated using ACI 318-08 do not agree well with tested capacities for members with less than minimum stirrups. Two modified shear methods are proposed, which revise the diagonal crack spacing and concrete contribution area assumed by S6-06. The modified shear methods improve predictions of shear capacity relative to predictions calculated using S6-06 and eliminate the issue of non-convergent shear capacity predictions which can result from evaluation using S6-06. / Structural Engineering

Obesity is a medical condition in which excess body fat has been accumulated. It is most commonly caused by imbalance between energy intake and energy expenditure (lack of physical activity and lower metabolic rate, etc.). The control of energy metabolism involves multiple tissues and signalling pathways and there is a great need for further understanding of these different interactions. In this study, I use Caenorhabditis elegans to study these complex pathways at the level of a whole organism. The downstream target of mTOR, p70 S6 kinase (S6K), has been implicated in the phosphorylation of multiple substrates and the regulation of growth and metabolism. In this study the worm homolog of S6K, rsks-1, found to be important for fat metabolism. Previous work in our lab found that RSKS-1::GFP is expressed at high levels in a set of sensory neurons and upregulated in ASJ, ASE and BAG sensory neurons in starved worms or mutants with low insulin activity. In this study, I found that the upregulation of rsks-1 expression was affected by serotonin, but not by the other neurotransmitters. Combined with the result that rsks-1 is required for the expression of TGFβ and insulin in ASI, rsks-1 may control dietary sensing by affecting insulin and TGFβ signalling within nervous system. Quantification of fat accumulation by TLC/GC revealed that in comparison to wild type worms, rsks-1 mutants have more than two-fold higher levels of triglycerides. This was confirmed by FT-IR microspectroscopy analysis. rsks-1 mutants also contain disproportionately high levels of C16:1n9 and C18:1n9 lipids compared with wild type worms. Genetic analysis has shown that rsks-1 acts either downstream of, or in parallel to the insulin and TGFβ pathways to affect fat levels. My studies showed that rsks-1 affects fat metabolism by influencing mRNA levels of genes encoding proteins in the β-oxidation pathway. Combined with defects in dietary sensing, fatty acid absorption, fertility and mitochondria function, the loss of rsks-1 activity induced much more energy storage than wild type by making a profound metabolic shift. These results are consistent with the metabolomics data analysis. Tissue specific RNAi showed that rsks-1 was required in many different tissues to regulate fat metabolism. Taken together, it can be concluded that RSKS-1 activity is needed for co-ordination of metabolic states in C. elegans. In order to understand more about the physiology behind fat accumulation, I analysed a mutant, aex-5, that has significantly lowered lipid levels. I found that this defect is associated with a significant reduction in the rate at which dietary fatty acids are taken up from the intestinal lumen. The aex-5 gene, which encodes a Kex2/subtilisin-family, Ca2+-sensitive proprotein convertase, is required for a discrete step in an ultraradian rhythmic phenomenon called the defecation motor program (DMP). Combined with other results, we conclude that aex-5 and other defecation genes may affect fat uptake by promoting the correct distribution of acidity within the intestinal lumen. This dissertation also described how to use Fourier transform infrared (FT-IR) microspectroscopy to detect lipids, proteins and carbohydrates directly in single worm. In conclusion, in this thesis I have uncovered several components that play roles in dietary sensing, fatty acid synthesis, adiposity regulation and fatty acid absorption in C. elegans.

No description available.

The aim of this study was to develop an <I>in vitro</I> mammary model, based on rat mammary explants, which could be used to examine the effects of amino acid profile and concentration in the media on protein synthesis. Secondly, to ascertain whether these responses to amino acids, in particular leucine and α ketoisocaproic acid, were transmitted through the mTOR/p70 S6 kinase signalling pathway. Mammary explant protein synthesis was found to be stimulated up to twofold in response to graded levels of a complete mixture of amino acids (2 x and 4 x, normal rat plasma concentrations). The acute (1 h) stimulation of protein synthesis was at the level of translation. Inhibition of mTOR by rapamycin did not block the stimulation of protein synthesis by amino acids. In fact, when total amino acid concentrations were increased 0.5 to 4-fold, p70 S6 kinase activity decreased, despite the fact that protein synthesis was elevated up to 2.5 fold. When explants were incubated with either leucine or its transamination product α ketoisocaproic acid at 4 x normal levels in the presence of other amino acids (1 x), p70 S6 kinase activity was increased. There was a tendency for p70 S6 kinase activity to be blocked when transamination was inhibited. The failure to decrease protein synthesis by inhibition of transamination, despite the fact that p70 S6 kinase activity was inhibited, suggests that other translation factors may be more important in regulating mammary protein synthesis. This Phd thesis demonstrates a novel role for amino acids in mammary protein synthesis, whereby amino acids modulate the activity of the translation regulator p70 S6 kinase. In particular leucine and its transamination are important in the regulation of p70 S6 kinase activity. This provides the starting point for future studies exploring the role of translation factors in the regulation of mammary protein synthesis.

This investigation aims to assess issues of physical, sensory and intellectual access to museums and galleries in Scotland, with a particular relevance to people with sight difficulties. The research has been completed from the point of view of the visually impaired visitor, using original fieldwork comprising visits to museums accompanied by people with different types of sight difficulties. An examination of the facilities provided has been undertaken from the visitors' perspective alongside the current and forthcoming legislative requirements. The opinions of the museums' community have been taken into consideration primarily by discussions with the curators of the museums and galleries visited. An appreciation of the legislative stimulus for museums and galleries to consider people with disabilities, the Disability Discrimination Act 1995, is also attempted, including reports from the MPs involved in the development and the introduction of this legislation and the MSPs with responsibilities for the representation of people with disabilities in the Scottish Parliament. A particular focus is applied to the introduction of Part 111 of the legislation which was enacted during the research period and used as a stimulus for the areas of questioning with the visually impaired people who assisted. This facilitates the presentation of a context against which to place the findings of the discussions with visually impaired people. Visitors are an essential requirement for the existence and future of museums and galleries and the potential audience of people with visual impairments is increasing and significant.

Thesis advisor: Michelle M. Meyer / As the factory responsible for producing proteins, ribosomes are of great importance. In bacteria, ribosomes are composed of three ribosomal RNAs (rRNA) of different sizes, and around 50 ribosomal proteins (r-protein). During ribosome biogenesis in bacteria, synthesis of rRNAs and r-proteins are both tightly regulated and coordinated to ensure robust growth. In particular, a group of cis-regulatory RNA elements located in the 5' untranslated regions or the intergenic regions in r-protein operons are responsible for the regulation of r-protein biosynthesis. Based on the fact that RNA-regulated r-protein biosynthesis is essential and universal in bacteria, such unique and varied regulatory RNAs could provide new targets for antibacterial purpose. In this thesis, we report and experimentally verify a novel r-protein L1 regulation model that contains dual L1-binding RNA motif, and for the first time, a S6:S18 dimer-binding RNA structure in the S6 operon. We also describe Escherichia coli-based and Schizosaccharomyces pombe-based reporter systems for in vivo characterization of RNA-protein interactions. So far, both in vivo systems failed to report RNA-protein interactions, and thus need further tuning. In addition, we performed phage-display to select for regulatory RNA-binding small peptides and examined their effects on bacteria viability. One selected peptide, N-TVNFKLY-C, caused defective growth when overexpressed in E. coli. Yet, further studies must be conducted to verify the possibility that bacteria were killed by direct RNA-peptide interaction that disrupted the native r-protein regulation. / Thesis (MS) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.

Includes bibliography. / 150 p. : ill ; 35 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis - University of Adelaide, 1951

London is not only a backdrop in the novels of Charles Dickens. Its workings both conceal truth of various sorts from characters and push it into the open. This thesis claims that it is the primary symbolic means by which Dickens dramatizes the conflict between concealment and revelation which provides the driving force of his fiction. The first chapter discusses how the city extrapolates the gothic motif of the haunted castle - a built environment which attempts to cut off connections with the rest of the world, leading to a state of atrophy and death. The second particularly explores urban squalor as evidence that human relationships have been obscured and that death is the result. Chapter three explores the kind of concealments and deaths effected by London and explains that the regenerative revelation required as an antidote to them is both social and religious in character. Dickens conceptualizes it as a participation in a familial system of love relationships originating in God's love for his children. The fourth and fifth chapters deal with two parts of London's organisation that bring knowledge inexorably to light, the detective police force and the railway network. They are part of a city that hides truth and brings it to light according to a carefully laid plan. Chapters six and seven consider two sub-symbols, the Thames and the crowd, that reflect the city's dual role in bringing both death and regeneration, both concealment and discovery. Characters' immersion in these brings about a death to their old identity and often a re-emergence into a new identity, based on the scheme of interconnections, that is both a revelation and an induction into new life. The mysteries worked out by Dickens's symbolic London are therefore an imaginative engagement with Christianity as a mystery religion, promising revelatory regeneration through surrender to death in the modern world.