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An enquiry into new methodologies for evaluating sustainable urban formOsmond, Paul William Hughes, Built Environment, Faculty of Built Environment, UNSW January 2008 (has links)
The motivation for this research is a perceived gap in knowledge regarding the complex relationships between the physical form of the urban environment; its environmental performance as expressed through stocks and flows of materials and energy (urban metabolism); and its experienced physical and psychological qualities (urban ambience). The objective is to develop a practical methodological structure which, through investigating the relationships between these domains, may help inform the evaluation, design and development of more sustainable human settlements. One expression of this apparent knowledge gap is the ambiguity around the classification of urban form and identification of a suitable taxonomic framework to support analysis. Urban morphological research and practice is critically reviewed to derive a rigorous definition of the 'urban structural unit' (USU) to facilitate the subdivision and description of urban form across spatial scales. Application of this construct to a study site in Sydney, Australia provides the basis for subsequent exploration. Investigation of theoretical and applied perspectives on urban ecology, metabolism and design enables distillation of a utilitarian set of structural, functional and ambience properties of the USU. A variety of quantitative methods pertinent to evaluation of these properties is systematically examined to derive a streamlined analytical methodology, integrating hemispherical image analysis, space syntax, isovist and material accounting methods within the USU framework. The efficacy of this methodological 'toolkit' is tested in the final, empirical stage of the research, focussing mainly on the campus of the University of New South Wales. Determination of a range of material, microclimatic, ecosystemic, fractal, syntactic and isovist metrics provides a preliminary quantitative description of the campus USU in terms of its interrelated metabolic and ambience properties. This is further explained and interpreted through multivariate statistical analysis. The results suggest that the USU represents a robust framework for urban evaluation, and application of a relatively parsimonious suite of analytical methods enables a useful initial examination of the relations between significant aspects of urban form, metabolism and ambience. The outcomes of such an evaluation can directly inform built environment practice from a sustainability perspective, and also highlight areas for more detailed investigation.
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Structure and physical properties of surfactant and mixed surfactant films at the solid-liquid interface.Blom, Annabelle January 2005 (has links)
The adsorbed layer morphology of a series of surfactants under different conditions has been examined primarily using atomic force microscopy (AFM). The morphologies of single and double chained quaternary ammonium surfactants adsorbed to mica have been characterised using AFM at concentrations below the cmc. Mixing these different types of surfactants systematically allowed a detailed examination of the change in adsorbed film curvature from the least curved bilayers through to most curved globules. From this study a novel mesh structure was discovered at curvatures intermediate to bilayers and rods. A mesh was again observed in studies examining the morphology change of adsorbed nonionic surfactant films on silica with variation in temperature. Other surfactant mixtures were also examined including grafting non-adsorbing nonionic surfactants and diblock copolymers into quaternary ammonium surfactant films of different morphologies.
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Tubificids with trifid chaetae: morphology and phylogeny of <i>Heterodrilus</i> (Clitellata, Annelida)Sjölin, Erica January 2007 (has links)
<p><i>Heterodrilus</i> is a marine group of small (3-25 mm) clitellates that occur interstitially in sandy sediments from the intertidal zone down to about 150 m depths. The taxon includes 42 valid species and has been recorded from localities in the Mediterranean Sea, the North-west Atlantic Ocean (including the Caribbean), the Galapagos Islands, and the Indo-Pacific Region. A majority of the species of <i>Heterodrilus</i> are characterized by having trifid anterior chaetae (i.e., chaetae with three teeth at the distal end). A few species have bifid chaetae, but these are regarded as having lost the third tooth secondarily. Within the taxon, species are distinguished by morphological characters in the internal organization of the male and female genitalia, but also by characters in the form and number of chaetae. In this thesis, two new taxa are introduced, <i>Heterodrilus tripartitus </i>and <i>H. ursulae</i>, both from the Mediterranean Sea. The ultrastructure of the cuticle in four species (<i>H. paucifascis, H. pentcheffi, H</i>. <i>flexuosus, H. minisetosus</i>) is studied and it is shown that there is interspecific variation in the morphology of the cuticle. One of the studied species, <i>H. paucifascis</i>, shows intraspecific variation, which is associated with sample locality. The systematic position of <i>Heterodrilus</i> within Tubificidae is studied with molecular markers, and the results support that <i>Heterodrilus </i>(earlier classified as a member of Rhyacodrilinae) is positioned within Phallodrilinae. Furthermore, the phylogenetic relationships within <i>Heterodrilus</i> are estimated based on molecular characters from mitochondrial COI, the 16S rRNA gene, and the nuclear 18S rRNA gene, and the result indicate that the two major clades in our tree corresponds to different geographical distributions. This thesis also includes a checklist, as well as a key, to the species of <i>Heterodrilus</i>.</p>
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The effect of redoxmodulation on osteoclastogenesisWitte, Sara January 2010 (has links)
<p>During osteoclast differentiation and bone resorption the redox status in the cell display a decrease in reduction and a shift to an oxidized state. Structure, metabolism and function are some of the extensive changes that cells undergo during differentiation which alters both the extra- and intracellular redox environment. Osteoclasts express enzymes such as TRAP and NADPH oxidase which generates reactive oxygen species (ROS). ROS are molecules formed by oxygen reduction which gives these radicals at least one unpaired electron and makes them very reactive and chemically unstable. These are factors which stimulates differentiation of osteoclasts and bone resorption. RAW 264.7 cells will differentiate to osteoclasts when stimulated with RANKL and to activated macrophages when stimulated with LPS.</p><p>The aim of this project was to analyze if the redox environment is affected during differentiation of RAW 264.7 cells to osteoclasts and macrophages. The reason for this was that we aimed to se if RAW 264.7 cells could be used as an in vitro system to study the effects of redox changes in osteoclasts and macrophages and their activation.</p><p>Results from Western blot showed that protein expression of the Cysteine/Glutamate transporter xCT was up regulated with LPS and downregulated with RANKL. Results from the GSH/Cys assay show that the treatments with redox modulators did not affect the levels of GSH and Cys to a measurable extent. However the levels increased for both intracellular and extracellular GSH and Cys forms at day 4 in the control and stimulated cells. Addition of the disulfide reductant DTT affected differentiation to osteoclasts, leading to smaller osteoclasts probably due to interference with fusion of mononuclear pre-osteoclasts. Thus, down regulation of the xCT transporter could be an important mechanism to maintain a low level of free thiols shown to interfere with the differentiation to osteoclasts.</p>
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Genetic requirements for the assembly and cell-to-cell movement of the beet yellows virusAlzhanova, Dina 23 July 2004 (has links)
Beet yellows virus (BYV) is a filamentous, positive-strand RNA virus that belongs to the family Closteroviridae. BYV particles encapsidate a 15.5 kb RNA and posses complex polar architecture. A long virion body is formed by the major capsid protein(CP), whereas the minor capsid protein (CPm) assembles a short tail that encapsidates the 5'-terminal region of BYV RNA. In addition to proteins required for viral RNA replication and encapsidation, BYV encodes four proteins whose role in the virus life cycle was unknown. These proteins include a small, 6-kDa, hydrophobic protein (p6), a homolog of the cellular 70-kDa heat shock proteins (Hsp7Oh), a 64-kDa protein (p64), and a 20-kDa protein (p20). It was found recently that Hsp7Oh, p64, and p20 are incorporated into BYV virions, and that Hsp7Oh is required for the virus movement from
cell to cell.
In this study, we characterized genetic requirements for BYV assembly and cell-to-cell movement, and determined relationships between these two processes. It was demonstrated that in addition to Hsp7Oh, p6, p64, CP, and CPm are each essential, but not sufficient for virus movement. These results indicated that five-component movement machinery of BYV is the most complex among plant viruses. Extensive mutational analysis of CP and CPm revealed strong correlation between abilities of BYV to assemble tailed virions and to move from cell to cell, suggesting that formation of functional virions is a prerequisite for virus translocation. We have found that CPm, Hsp7Oh, and p64 are necessary for the efficient virion tail formation. Assembly of the virion tails and bodies was shown to occur independent of each other and likely to involve two separate packaging signals within the genomic RNA.
Our work demonstrated that BYV encodes one conventional movement protein, p6,
whose only known function is to mediate virus movement. The other four movement associated proteins of BYV, CP, CPm, Hsp7Oh, and p64 are the virion components, each of which is required for assembly of the tailed, movement-competent virions. Based on these and other data, we propose that BYV and other closteroviruses evolved virion tails as a specialized device for the directional cell-to-cell movement of large RNA genomes. / Graduation date: 2005 / Best scan available.
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Dual bayesian and morphology-based approach for markerless human motion capture in natural interaction environmentsCorrea Hernandez, Pedro 30 June 2006 (has links)
This work presents a novel technique for 2D human motion capture using a single non calibrated camera. The user's five extremities (head, hands and feet) are extracted, labelled and tracked after silhouette segmentation. As they are the minimal number of points that can be used in order to enable whole body gestural interaction, we will henceforth refer to these features as crucial points. The crucial point candidates are defined
as the local maxima of the geodesic distance with respect to the center of gravity of the actor region which lie on the silhouette boundary. In order to disambiguate the selected crucial points
into head, left and right foot, left and right hand classes, we propose a Bayesian method that combines a prior human model and the intensities of the tracked crucial points. Due to its low
computational complexity, the system can run at real-time paces on standard Personal Computers, with an average error rate range between 2% and 7% in realistic situations, depending on the
context and segmentation quality.
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Femtosecond laser processing of crystalline siliconTran, D. V., Lam, Yee Cheong, Zheng, H. Y., Murukeshan, V. M., Chai, J.C., Hardt, David E. 01 1900 (has links)
This paper reports the surface morphologies and ablation of crystalline silicon wafers irradiated by infra-red 775 nm Ti:sapphire femtosecond laser. The effects of energy fluences (below and above single-pulse modification) with different number of pulses were studied. New morphological features such as pits, cracks formation, Laser-Induced Periodic Surface Structures (LIPSS) and ablation were observed. The investigation indicated that there are two distinct mechanisms under femtosecond laser irradiation: low fluence regime with different morphological features and high fluence regime with high material removal and without complex morphological features. / Singapore-MIT Alliance (SMA)
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Improving the Effectiveness of Laying Hens for Use in Value-Added Egg Production.Nain, Sandeep 06 1900 (has links)
A series of experiments were conducted to explore factors affecting transfer of value-added ingredients from the diet to table eggs, with the goal of contributing to improvements in the enrichment process.
Flaxseed-based ω-3 PUFA enrichment did not reduce lutein enrichment. The combine enrichment of lutein and ω-3 PUFA had decresed lipid oxidation potential. Also, when fed a ω-3 PUFA diet, birds scored as energetic Efficient had longer and wider villi, resulting in greater absorptive surface area/villi than Non-efficient hens. However, histomorphological differences did not affect transfer of ω-3 PUFA from diet to egg. Finally, birds fed graded levels of ω-3 PUFA to characterize change in lipid profile of egg and blood plasma in time reached a plateau in total ω-3 PUFA/egg in 5.9 to 6.6d, with High birds reaching the target of 300 mg/egg in 5d. Egg enrichment can be modulated by changes to the hen diet. / Animal Science
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Does Meaning Matter For Reading Achievement? Untangling the Role of Phonological Recoding and Morphological Awareness in Predicting Word Decoding, Reading Vocabulary, and Reading Comprehension Achievement for Spanish-Speaking English Language LearnersGoodwin, Amanda P. 11 June 2010 (has links)
This study examined the unique contributions of morphological awareness and phonological recoding to word decoding, reading comprehension, and reading vocabulary for 197 Spanish-speaking English language learners enrolled in the fifth grade. The study also explored the contribution of phonological recoding, measured by accuracy on a pseudo-word decoding task, to the prediction of the same components of reading achievement. Specifically the study explored whether the contribution of phonological recoding changed when morphological awareness and oral vocabulary (a mediator of reading achievement) were added as predictors. To examine unique contributions, morphological awareness was separated from phonological and orthographic confounds present in opaque morphological relationships by using structural equation modeling to construct a latent variable stemming from the shared variance of four morphological tasks with different levels of morphological transparency, and therefore different phonological and orthographic processing demands. A latent variable of phonological recoding was also created. Findings indicated that when controlling for phonological recoding, morphological awareness made a significant and meaningful contribution to passage comprehension and reading vocabulary, but not word decoding with oral vocabulary acting as a significant mediator of this relationship. The study also found that phonological recoding was a significant predictor of each reading outcome when morphological awareness was not included as a predictor, but only significantly predicted word reading when controlling for morphological awareness. Significance of these findings to research and the need for additional morphological instruction within educational settings are discussed.
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An Evaluation of Existing Light Stemming Algorithms for Arabic Keyword SearchesBrittany E. Rogerson 17 November 2008 (has links)
The field of Information Retrieval recognizes the importance of stemming in improving retrieval effectiveness. This same tool, when applied to searches conducted in the Arabic language, increases the relevancy of documents returned and expands searches to encompass the general meaning of a word instead of the word itself. Since the Arabic language relies mainly on triconsonantal roots for verb forms and derives nouns by adding affixes, words with similar consonants are closely related in meaning. Stemming allows a search term to focus more on the meaning of a term and closely related terms and less on specific character matches. This paper discusses the strengths of light stemming, the best techniques, and components for algorithmic affix-based stemmers used in keyword searching in the Arabic language.
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