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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Segmentation and Line Filling of 2D Shapes

Pérez Rocha, Ana Laura 21 January 2013 (has links)
The evolution of technology in the textile industry reached the design of embroidery patterns for machine embroidery. In order to create quality designs the shapes to be embroidered need to be segmented into regions that define different parts. One of the objectives of our research is to develop a method to automatically segment the shapes and by doing so making the process faster and easier. Shape analysis is necessary to find a suitable method for this purpose. It includes the study of different ways to represent shapes. In this thesis we focus on shape representation through its skeleton. We make use of a shape's skeleton and the shape's boundary through the so-called feature transform to decide how to segment a shape and where to place the segment boundaries. The direction of stitches is another important specification in an embroidery design. We develop a technique to select the stitch orientation by defining direction lines using the skeleton curves and information from the boundary. We compute the intersections of segment boundaries and direction lines with the shape boundary for the final definition of the direction line segments. We demonstrate that our shape segmentation technique and the automatic placement of direction lines produce sufficient constrains for automated embroidery designs. We show examples for lettering, basic shapes, as well as simple and complex logos.
42

Studies on the Steroidal Natural Products from Formosan Gorgonian Isis hippuris

Chao, Chih-Hua 23 July 2003 (has links)
Several terpenoids isolated from a Formosan gorgonian coral Isis hippuris have shown significant cytotoxic activity against various cancer cell lines. In our studies, the EtOAc and n-Hexane extracts showed potent cytotoxic response toward P-388, A549 and HT-29 cancer cell lines. In order to search other active components, we have studied the chemical constituents of I. hippuris from a Green Island specimen. Thus, the investigation on the chemical content of this extract was carried out. After our hard working, we haved isolated eleven new steroids (1- 11) , A-nor-2-carboxy-22-epi-hippurin-1 (1)¡B2a-acetoxy-3a-hydroxy- 11b-hydroxy-24-methyl-22,25-epoxy-5a-furostan-18,20b-lactone (2)¡B2a,3a-dihydroxy-11b-hydroxy-24-methyl-22,25-epoxy-5a-furostan-18,20b-lactone (3)¡B2a-hydroxy-3a-acetoxy-11b-hydroxy-24-methyl-22, 25-epoxy-5a-furostan-18,20b-lactone (4)¡B2a-hydroxy-3a-acetoxy-24- methyl-11b,18;18,20b;22,25-triepoxy-5a-furostane (5)¡B2a-acetoxy- 3a-hydroxy-24-methyl-11b,18;18,20b;22,25-triepoxy-5a-furostane (6)¡Bhippuristerone K (7)¡Bhippuristerone L (8)¡B hippuristerol F (9)¡B1a, 3b,5b,11a-tetrahydroxy gorgostan-6-one (10)¡B22-epi-hippuristan-11-one (11). We also isolated two known compounds, 22-epi- hippuristanol (19)¡B 2-desacetyl-22-epi-hippurin-1 (25). The structures of new compounds (1-11) were elucidated by spectroscopic evidences (IR, MS, 1D NMR, 2D NMR) and the comparison of literature. Among those, the stereochemistry of compound 1, with a new skeleton, were confirmed by single-crystal X-ray diffraction analyses. Unfortunately, because of the poor yield, the cytotoxicity test can not be carry out. But now, we try to get enough by semisynthesis.
43

Mechanisms of impaired osteoblast function during disuse

Allen, Matthew Robert 15 November 2004 (has links)
Prolonged periods of non-weightbearing activity result in a significant loss of bone mass which increases the risk of fracture with the initiation of mechanical loading. The loss of bone mass is partially driven by declines in bone formation yet the mechanisms responsible for this decline are unclear. To investigate the limitations of osteoblasts during disuse, marrow ablation was superimposed on hindlimb unloaded mice. Marrow ablation is a useful model to study osteoblast functionality as new cancellous bone is rapidly formed throughout the marrow of a long bone while hindlimb unloading is the most common method used to produce skeletal unloading. The specific hypotheses of this study were aimed at determining if changes in osteoblast functionality, differentiation, and/or proliferation were compromised in non-weightbearing bone in response to a bone formation stimulus. Additionally, the influence of having compromised osteoblast functionality at the time of stimulation was assessed in non-weightbearing bones. Key outcome measures used to address these hypotheses included static and dynamic cancellous bone histomorphometry, bone densitometry, and real-time polymerase chain reaction (PCR) analyses of gene expression. The results document similar ablation-induced increases of cancellous bone in both weightbearing and unloaded animals. Similarly, there was no influence of load on ablation-induced increases in cancellous bone forming surface or mineral apposition rate. Unloading did significantly attenuate the ablation-induced increase in bone formation rate, due to reduced levels of total surface mineralization. When osteoblast functionality was compromised prior to marrow ablation, bone formation rate increases were also attenuated in ablated animals due to reduced mineralization. Additionally, increases in forming surface were attenuated as compared to unloaded animals having normal osteoblast function at the time of ablation. Collectively, these data identify mineralization as the limiting step in new bone formation during periods of disuse. The caveat, however, is that when bone formation is stimulated after a period of unloading sufficient to compromise osteoblast functionality, increases in osteoblast recruitment to the bone surface are compromised.
44

The form of the talus with special reference to that of the Australian aborigine

Inkster, R. G. January 1927 (has links)
No description available.
45

Applying Next Generation Sequencing to Skeletal Development and Disease

Bowen, Margot Elizabeth 04 August 2014 (has links)
Next Generation Sequencing (NGS) technologies have dramatically increased the throughput and lowered the cost of DNA sequencing. In this thesis, I apply these technologies to unresolved questions in skeletal development and disease. Firstly, I use targeted re-sequencing of genomic DNA to identify the genetic cause of the cartilage tumor syndrome, metachondromatosis (MC). I show that the majority of MC patients carry heterozygous loss-of-function mutations in the PTPN11 gene, which encodes a phosphatase, SHP2, involved in many signaling pathways. Furthermore, I show that cartilage lesions in MC patients likely arise following somatic second-hit mutations in PTPN11. Secondly, I use RNA-seq to identify gene expression changes that occur following genetic inactivation of Ptpn11 in mouse chondrocyte cultures. I show that chondrocytes lacking Ptpn11 fail to properly undergo terminal differentiation and instead continue to express genes associated with earlier stages of chondrocyte maturation. I validate these findings in vivo by examining markers of specific chondrocyte maturation stages in the vertebral growth plates of mice following postnatal mosaic inactivation of Ptpn11. Together, my results provide insight into the molecular mechanisms underlying the initiation and growth of cartilage tumors. In the third component of my thesis, I develop a method to map and clone zebrafish mutations by performing whole genome sequencing on pooled DNA. I apply this method to zebrafish mutants identified in a mutagenesis screen for adult phenotypes, including skeletal phenotypes, and determine that a nonsense mutation in bmp1a underlies the craniofacial phenotype in the wdd mutant. In summary, I show that NGS technologies can be successfully utilized to firstly identify the genetic cause of a human skeletal disorder, secondly investigate the molecular mechanisms regulating the maturation of skeletal cells, and thirdly expedite the process of mapping and cloning zebrafish mutants with skeletal phenotypes. Altogether, my research provides insight into the pathways and processes regulating skeletal development and disease.
46

Providing Support for the Movidius Myriad1 Platform in the SkePU Skeleton Programming Framework

Cuello, Rosandra January 2014 (has links)
The Movidius Myriad1 Platform is a multicore embedded platform primed to offer high performance and power efficiency for computer vision applications in mobile devices. The challenges of programming multicore environments are well known and skeleton programming offers a high-level programming alternative for parallel computing, intended to hide the complexities of the system from the programmer. The SkePU Skeleton Programming Framework includes backend implementations for CPU and GPU systems and it has the capacity to support more platforms by extending its backend implementations. With this master thesis project we aim to extend the SkePU Skeleton Programming Framework to provide support for execution in the Movidius Myriad1 embedded platform. Our SkePU backend for Myriad1 consists on a set of macros and functions to compose the different elements of a Myriad1 application, data communication structures to exchange data between the host systems and Myriad1, and a helper script and auxiliary files to generate a Myriad1 application.Evaluation and testing demonstrate that our backend is usable, however further optimizations are needed to obtain good performance that would make it practical to use in real life applications, particularly when it comes to data communication. As part of this project, we have outlined some improvements that could be applied to obtain better performance overall in the future, addressing the issues found with the methods of data communication.
47

AMP-activated protein kinase (AMPK) and calcium/calmodulin-dependent protein kinase II (CAMKII) activation in exercising human skeletal muscle / Adenosine monophosphate activated protein kinase (AMPK) and calcium calmodulin dependent protein kinase II (CAMKII) activation in exercising human skeletal muscle

Haus, Jacob M. January 2004 (has links)
There is no abstract available for this thesis. / School of Physical Education
48

Segmentation and Line Filling of 2D Shapes

Pérez Rocha, Ana Laura 21 January 2013 (has links)
The evolution of technology in the textile industry reached the design of embroidery patterns for machine embroidery. In order to create quality designs the shapes to be embroidered need to be segmented into regions that define different parts. One of the objectives of our research is to develop a method to automatically segment the shapes and by doing so making the process faster and easier. Shape analysis is necessary to find a suitable method for this purpose. It includes the study of different ways to represent shapes. In this thesis we focus on shape representation through its skeleton. We make use of a shape's skeleton and the shape's boundary through the so-called feature transform to decide how to segment a shape and where to place the segment boundaries. The direction of stitches is another important specification in an embroidery design. We develop a technique to select the stitch orientation by defining direction lines using the skeleton curves and information from the boundary. We compute the intersections of segment boundaries and direction lines with the shape boundary for the final definition of the direction line segments. We demonstrate that our shape segmentation technique and the automatic placement of direction lines produce sufficient constrains for automated embroidery designs. We show examples for lettering, basic shapes, as well as simple and complex logos.
49

The comparative anatomy of the hominoid cranial base

Dean, Michael Christopher January 1982 (has links)
This thesis uses metrical data and morphological observations to describe the comparative anatomy of the cranial base region in extant adult hominoids. The changes that occur during growth in this region have also been studied in samples of juvenile hominoids, and cross-sectional growth data for the same variables measured in the adult metrical study have been recorded. Detailed metrical and morphological observations were also made on a series of fossil hominid crania dating from the Plio- Pleistocene. The results of the two comparative studies of the cranial base region in extant hominoids were then used to assess the significance of the differences noted in the cranial base region of the fossil hominids from sites in South and East Africa. The results of the adult metrical study; and the series of soft tissue dissections, demonstrate that there are fundamental differences in the comparative anatomy of the modern human and pongid cranial bases. The results of the comparative growth study indicate that these differences are probably not the result of an overall acceleration, or retardation, in growth rates of the component bones of the human cranial base, but more likely due to a combination of increases and decreases in growth rates occurring in individual bones, as well as to differences in morphology already manifest soon after birth. The results of the study of fossil hominid specimens indicate that the 'gracile' australopithecine fossils from South Africa have a cranial base pattern similar to that of the extant pongid samples, but that the 'robust' australopithecine fossils, and those fossils attributed to early Homo have a cranial base pattern more similar hominid fossil specimens which are still of uncertain taxonomic designation. The comparative studies of the hominoid cranial base also provide a framework which enables features of this region to be used in phylogenetic analysis. to the modern Homo sapiens sample. These differences in basicranial anatomy among the fossil hominid sample provide a useful tool to assess the taxonomic status of several
50

Dental age determination in South Australian children : thesis submitted in partial fulfillment of the requirements for the degree of Master of Dental Surgery /

Stephen, Soni. January 1999 (has links) (PDF)
Thesis (M.D.S.)--University of Adelaide, Dept. of Dentistry, 1999. / Bibliography: leaves 158-182.

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