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Thesis--University of Wisconsin--Madison. / Typescript. Vita. Includes bibliographical references (leaves 158-173).

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Origami has become a source of inspiration in a number of engineered systems. In most systems, non-paper materials where material thickness is non-negligible is required. In origami-inspired engineered systems where thickness is non-negligible, thickness-accommodation techniques must be utilized to overcome the issue of self-intersection. Many thickness-accommodation techniques have been developed for use in thick-origami-inspired-engineered systems. In this work several thickness-accommodation techniques are reviewed and discussed. New thickness-accommodation techniques including hybrid thickness-accommodation techniques and the split vertex technique are presented and discussed. These techniques enable new capabilities of thickness-accommodation in origami adapted design. Thickness-accommodation techniques have been developed in the context of developable origami patterns and the application of these techniques to non-developable patterns is introduced here. The capability of non-developable thick origami is demonstrated in an application example of a deployable locomotive nose-fairing.

(Uncorrected OCR) Abstract of thesis entitled NOVEL ASPECTS OF AUTOCRINEIP ARACRINE REGULATION OF GROWTH HORMONE SECRETION AND SYNTHESIS IN GRASS CARP PITUITARY CELLS Submitted by ZHOUHONG for the degree of Doctor of Philosophy at The University of Hong Kong in March 2003 In this study, autocrine/paracrine regulation of growth hormone (GH) synthesis and secretion by local interactions of gonadotrophs and somatotrophs was examined in vitro in pituitary cells prepared from Chinese grass carp (Ctenopharyngodon idellus). Treatment with exogenous OH and gonadotropin (OTH) resulted in a dose-dependent increase in basal GH release, GH production, and GH mRNA levels. However, the opposite effects were observed by removing endogenous OR and OTH using immunoneutralization. Furthermore, GR and OTH immunoneutralizations at the pituitary level were effective in blocking the stimulatory influence on GH mRNA expression induced by GH-releasing factors in fish, including GnRH, dopamine, and PACAP38�Apparently" GH-induced GH gene expression was mediated by increasing the T1/2 ofGH mRNA in the cytoplasm and enhancing the production of GH primary transcripts in the nucleus. Since GH-induced OR mRNA gene expression could be blocked by inhibiting JAK2, P42144MAPK, P38MAPK, and PI3K, it is likely that the JAK/MAPK and JAK/PI3K pathways are involved in the GH receptor signaling. Similarly, exogenous GTH increased the production ofGH primary transcripts. However, it did not improve OR mRNA stability but rather enhanced the turnover of GH transcripts. GTR also increased cAMP production in carp pituitary cells. GTH-induced GH mRNA expression Was mimicked by activating cAMP synthesis and blocked by inhibiting adenylate cyclase (AC) and PKA.. GTH-induced OR mRNA expression was also sensitive to inhibition of JAKz, P42/44MAPK, P3SM.AP1C and PI3K. Similar inhibitions, except for PI3K, were all effective in blocking OR mRNA expression induced by activation of cAMP synthesis. These results indicate that GTH may induce GR gene expression through the AC/ cAMP/PKA pathway secondary coupled to JAK.2 andlor MAPK. Apparently, a cAMP-independent PI3K component is also involved in the post-receptor signaling. Using a colunm perifusion approach, the dynamic interactions between somaotrophs and gonadotrophs were examined. In this case, exogenous OTR induced a rapid rise in basal GH secretion, whereas exogenous GR was found to inhibit basal GTR release. In parallel studies, GTHinduced OR mRNA expression was abolished by OR immunoneutralization. Similarly, GTR immunoneutralization blocked GR-induced OR mRNA expression in carp pituitary cells. These results, as a whole, indicate that endogenously secreted OH and GTR, besides their functions as endocrine hormones, serve as novel autocrine/paracrine factors at the pituitary level to modulate GH secretion, OH production, OH gene expression, and somatotroph sensitivity to stimulation by hypothalamic regulators. These stimulatory influences of GH and GTR on OR gene expression axe exerted at the level of GR rnRNA stability and OH gene transcription, presumably via a direct coupling to the JAK/MAPK and JAKiPI3K cascades or an indirect coupling via the AC/cAMP/PKA pathway. Apparently, a local il1trapituitary feedback loop is present. In this case, GTH released from gonadotrophs stimulates GH secretion in neighboring somatotrophs. GR release from somatotrophs is essential to maintain basal GH synthesis and secretion and also exerts a negative feedback on basal GTB release. This intrapituitary feedback loop formed by local interactions between gonadotrophs and somatotrophs may represent a novel mechanism to control OR gene expression in lower vertebrates. / abstract / toc / Zoology / Doctoral / Doctor of Philosophy

A wide variety of proteins which are synthesised in the cytoplasm of E. coli are subsequently directed either to non-cytoplasmic compartments or transported to the extracellular medium. Proteins which are exported from the cytoplasm are thought to interact with a complex cellular machinery and a number of mutations affecting this secretion machinery have been isolated. In this study, the export of the outer membrane protein TonA was used as a model system to examine the effect on protein translocation of two temperature sensitive secretion mutants, secA and secY. Initial analysis of the effect of secAts mutations on bulk envelope protein synthesis confirmed the key role of SecA in protein transport, including many proteins assembled into the inner membrane. Analysis of the rate of processing of preTonA, pulse-labelled at the restrictive temperature and chased at the permissive temperature revealed differences between SecA and SecY mutants. In particular these data indicate that SecA and SecY may interact sequentially to promote protein export and that SecA may be required to maintain preTonA in a translocationally competent form prior to interaction with SecY. In order to investigate the nature of a specific "export" signal within a protein to be exported, the possibility of using the novel secretion signal at the C-terminus of E. coli haemolysin to direct chimeric protein into the medium was also investigated. The C-terminal signal was successfully fused to a hybrid protein containing a few residues of ss-galactosidase and the majority of E. coli outer membrane protein OmpF lacking its own NH2-terminal signal sequence. The chimeric protein is specifically translocated across the inner and outer membranes and is released into the medium. Consistent with a transport system which bypasses the periplasm, other studies indicated that haemolysin transport is secA independent but may involve secY. Finally, the localisation of haemolysin and several outer membrane proteins synthesised in spheroplasts was also examined in the hope of gaining some further insight into the route taken by proteins which reach the outer membrane or the external medium.

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