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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.
391

Neonatal Identification Screening for Hearing Impairment: A Comparison of the Utah Maternal Questionnaire and Birth Certificate

Clark, Carl Hugh 01 May 1980 (has links)
The purpose of this study was to compare the Utah maternal questionnaire and birth certificate as they relate to the identification of hearing impairment in infants. Comparative data relating to rate of return, number of high risk infants, number of at risk infants, number of hearing impaired infants, false positive rates, and item analysis were obtained for both screening instruments. Tabulation of the results showed the birth certificate to be a better neonatal screening device of hearing impairment than the maternal questionnaire. The birth certificate maintained a low false positive rate and a high rate of identification of hearing impairment in infants.
392

Application of Image Recognition Technology to Foraminiferal Assemblage Analyses

Gfatter, Christian Helmut 12 October 2018 (has links)
Analyses of foraminiferal assemblages involve time consuming microscopic assessment of sediment samples. Image recognition software, which systematically matches features within sample images against an image library, is widely used in contexts ranging from law enforcement to medical research. At present, scientific applications such as identification of specimens in plankton samples utilize flow through systems in which samples are suspended in liquid and pass through a beam of light where the images are captured using transmitted light. Identification of foraminifers generally utilizes reflected light, because most shells are relatively opaque. My goal was to design and test a protocol to directly image foraminiferal specimens using reflected light and then apply recognition software to those images. A library of high quality digital images was established by photographing foraminifers identified conventionally from sediment samples from the west Florida shelf. Recognition software, VisualSpreadsheet™ by Fluid Imaging Technologies, Inc., was then trained to improve automated assemblage counts and those results were compared to results from direct visual assessment. The auto classification feature produced composite accuracies of foraminiferal groups in the range of 60–70% compared to traditional visual identification by a researcher using a stereo microscope. Site SC34, the source of images for the original image library, had an initial accuracy of 75% that was improved slightly through an alteration to one of the software classes, but composite accuracy plateaued at 60% with the updated filters. Thus, image acquisition advancements and further development of image recognition software will be required to improve automated or semi automated foraminiferal classifications. However, other potential applications were noted. For example, an advantage of acquiring digital images of entire samples or subsamples is the ability to collect quantitative data such as diameter and length, allowing size-frequency assessments of foraminiferal populations while possibly automating grain size analyses without requiring separate processing. In addition, data files of library and sample specimens can be readily shared with other researchers.
393

Development of a multiplex Sequence Specific Primer (SSP)-PCR system to identify forensically relevant calliphoride

Hitchen, Yvette January 2008 (has links)
From the entomological evidence occurring on and around a corpse it is possible to determine an estimated post-mortem interval (PMI). The critical step in this examination is the accurate identification of specimens collected ensuring the application of appropriate species-specific developmental data. Current molecular techniques in the identification of forensically important Calliphoridae species from the Australian region have been explored and found to be a highly significant and valuable area of research. The cytochrome oxidase genes in the mitochondrial genome have been shown to have sufficient sequence diversity to distinguish forensically relevant Calliphoridae species. In order to target the observed sequence diversity within relevant regions of the nuclear or mitochondrial genomes, sequence specific primer (SSP) pairs are used to target polymorphisms, resulting in the amplification of specific species. This technique has proven to be both a rapid and successful identification tool in the analysis of insect taxa, especially Culicidae. SSP typing is particularly useful, as it requires no subsequent sequencing or restriction with enzymes, both of which require additional time and reagents. The aim of this research was to develop a multiplex SSP reaction for the identification of forensically important Calliphoridae species. Seven SSP pairs preliminarily designed by Harvey (2006) were utilised in the identification of Calliphora dubia, Calliphora albifrontalis, Chrysomya rufifacies, Chrysomya megacephala and Lucilia sericata. Once optimised the SSP pairs were developed into two multiplex PCR reactions. This thesis presents the experiments performed, analysis conducted and results obtained through the development of the multiplex SSP-PCR system. Initial testing of the seven preliminarily designed SSP pairs conveyed non-concordance between expected and observed results. Additional species were continually amplified, even after extensive optimisation attempts, including alternations to annealing temperature, MgCl2 and primer concentration. Of the 7 SSP pairs, 6 were re-designed to improve specificity, whilst one was removed from further testing and replaced with 2 newly designed primer pairs. 15 Continual testing of 8 SSP pairs was conducted, but only 6 could be successfully optimised. Optimisation was limited to alterations to annealing temperature, to allow for potential multiplexing. To confirm the regions and species amplified, sequencing of the PCR products was performed. Though only partial sequences were obtained for most samples the alignment shows the expected region amplified with specific species variations. Using the remaining 6 SSP pairs all species tested were identifiable, allowing for multiplexing potential to be tested. Multiplex PCR is a cost effective and efficient technique that is becoming increasing popular within a wide range of scientific disciplines. To date there has been no recorded use of this technique in relation to either forensic entomology or the analysis of forensically important Calliphoridae species. The 6 SSP pairs were manipulated to produce one successful multiplex PCR system using 3 SSP pairs to identify L. sericata, Ch. rufifacies and Ch. megacephala, and one unsuccessful multiplex PCR that amplified a single SSP pair for the identification of C. dubia and Ch. rufifacies. When both reactions are utilised, it is possible to identify all 5 forensically important Calliphoridae species tested.
394

The Identification of novel genes differentially expressed in Haemopoietic progenitor cells.

Gregorio-King, Claudia C, mikewood@deakin.edu.au January 2001 (has links)
The biochemical and molecular processes that maintain the stem cell pool, and govern the proliferation and differentiation of haemopoietic stem/progenitor cells (HSPCs) have been widely investigated but are incompletely understood. The purpose of this study was to identify and characterise novel genes that may play a part in regulating the mechanisms that control the proliferation, differentiation and self-renewal of human HSPCs. Reverse transcription differential display polymerase chain reaction (dd-PCR) was used to identify differences in gene expression between a HSPC population defined by expression of the CD34 phenotype, and the more mature CD34 depleted populations. A total of 6 differentially expressed complementary deoxyribonucleic acid (cDNA) sequences were identified. Four of these transcripts were homologous to well characterised genes, while two (band 1 and band 20) were homologous to unknown and uncharacterised partial gene sequences on the GenBank database and were thus chosen for further investigation. The partial cDNA sequences for band 1 and band 20 were designated ORP-3 and MERP-1 (respectively) due to homologies with other well-characterised gene families. Differential expression of the ORP-3 and MERP-1 genes was confirmed using Taqman™ real-time polymerase chain reaction (PCR) with 3 - 4-fold and 4-10 -fold higher levels in the CD34+ fractions of haemopoietic cells compared to CD34- populations respectively. Additionally, expression of both these genes was down regulated with proliferation and differentiation of CD34+ cells further confirming higher expression in a less differentiated subset of haemopoietic cells. The full coding sequences of ORP-3 and MERP-1 were elucidated using bioinformatics, rapid amplification of cDNA ends (RACE) and PCR amplification. The MERP-1 cDNA is 2600 nucleotides (nt) long, and localizes by bioinformatics to chromosome 7.. It consists of three exons and 2 introns spanning an entire length of 31.4 kilobases (kb). The MERP-1 open reading frame (ORF) codes for a putative 344 amino acid (aa) type II transmembrane protein with an extracellular C-terminal ependymin like-domain and an intracellular N-terminal sequence with significant homology to the cytoplasmic domains of members of the protocadherin family of transmembrane glycoproteins. Ependymins and protocadherins are well-characterised calcium-dependant cell adhesion glycoproteins. Although the function of MERP-1 remains to be elucidated, it is possible that MERP-1 like its homologues plays a role in calcium dependent cell adhesion. Differential expression of the MERP-1 gene in haemopoietic cells suggests a role in haemopoietic stem cell proliferation and differentiation, however, its broad tissue distribution implies that it may also play a role in many cell types. Characterization of the MERP-1 protein is required to elucidate these possible roles. The ORP-3 cDNA is 6631nt long, and localizes by bioinformatics to chromosome 7pl5-p21. It consists of 23 exons and 22 introns spanning an entire length of 183.5kb. The ORP-3 ORF codes for a putative 887aa protein which displays the consensus sequence for a highly conserved oxysterol-binding domain. Other well-characterised proteins expressing these domains have been demonstrated to bind oxysterols (OS) in a dose dependant fashion. OS are hydroxylated derivatives of cholesterol Their biological activities include inhibition of cholesterol biosynthesis and cell proliferation in a variety of cell types, including haemopoietic cells. Differential expression of the ORP-3 gene in haemopoietic cells suggests a possible role in the transduction of OS effects on haemopoietic cells, however, its broad tissue distribution implies that it may also play a role in many cell types. Further investigation of ORP-3 gene expression demonstrates a significant correlation with CD34+ sample purity, and 2-fold higher expression in a population of haemopoietic cells defined by the CD34+38- phenotype compared to more mature CD34+38+ cells. This finding, taken together with the previous observation of down-regulation of ORP-3 expression with proliferation and differentiation of CD34+ cells, indicates that ORP-3 expression may be higher in a less differentiated subset of cells with a higher proliferative capacity. This hypothesis is supported by the observation that expression of the ORP-3 gene is approximately 2-fold lower in differentiated HL60 promyelocytic cells compared to control, undifferentiated cells. ORP-3 expression in HL60 cells during normal culture conditions was also found to vary with expression positively correlated with cell number. This indicates a possible cell cycle effect on ORP-3 gene expression with levels highest when cell density, and therefore the percentage of cells in G(0)/G(1) phase of the cell cycle is highest. This observation also correlates with the observation of higher ORP-3 expression in CD34+38-cells, and in CD34+ and HL60 cells undergoing OS induced and camptothecin induced apoptosis that is preceded by cell cycle arrest at G(0)/G(1). Expression of the ORP-3 gene in CD34+ HSPCs from UCB was significantly decreased to approximately half the levels observed in control cells after 24 hours incubation in transforming growth factor beta-1 (TGFâl). As ≥90% of these cells are stimulated into cell cycle entry by TGFâl, this observation further supports the hypothesis that ORP-3 expression is highest when cells reside in the G(0)/G(1) phase of the cell cycle. Data obtained from investigation of ORP-3 gene expression in synchronised HL60 cells however does not support nor disprove this hypothesis. Culture of CD34+ enriched HSPCs and HL60 cells with 25-OHC significantly increased ORP-3 gene expression to approximately 1.5 times control levels. However, as 25-OHC treatment also increased the percentage of apoptotic cells in these experiments, it is not valid to make any conclusions regarding the regulation of ORP-3 gene expression by OS. Indeed, the observation that camptothecin induced apoptosis also increased ORP-3 gene expression in HL60 cells raises the possibility that up-regulation of ORP-3 gene expression is also associated with apoptosis, Taken together, expression of the ORP-3 gene appears to be regulated by differentiation and apoptosis of haemopoietic progenitors, and may also be positively associated with proliferative and G(0)/G(1) cell cycle status indicating a possible role in all of these processes. Given the important regulatory role of apoptosis in haemopoiesis and differential expression of the ORP-3 gene in haemopoietic progenitors, final investigations were conducted to examine the effects OS on human HSPCs. Granulocyte/macrophage colony forming units (CFU-GM) generated from human bone marrow (ABM) and umbilical cord blood (UCB) were grown in the presence of varying concentrations of three different OS - 7keto-cholesterol (7K-C), 7beta-hydroxycholesterol (7p-OHC) and 25-hydroxycholesterol (25-OHC). Similarly, the effect of OS on HL60 and CD34+ cells was investigated using annexin-V staining and flow cytometry to measure apoptosis. Reduction of nitroblue tetrazolium (NBT) was used to assess differentiative status of HL60 cells. CFU-GM from ABM and HL60 growth was inhibited by all three OS tested, with 25-OHC being the most potent. 25-OHC inhibited ≥50% of bone marrow CFU-GM and ≥95% of HL60 cell growth at a level of 1 ug/ml. Compared to UCB, CFU-GM derived from ABM were more sensitive to the effects of all OS tested. Only 25-OHC and 7(5-OHC significantly inhibited growth of UCB derived CFU-GM. OS treatment increased the number of annexin-V CD34+ cells and NBT positive HL60 cells indicating that OS inhibition of CFU-GM and HL60 cell growth can be attributed to induction of apoptosis and differentiation. From these studies, it can be concluded that dd-PCR is an excellent tool for the discovery of novel genes expressed in human HSPCs. Characterisation of the proteins encoded by the novel genes ORP-3 and MERP-1 may reveal a regulatory role for these genes in haemopoiesis. Finally, investigations into the effects of OS on haemopoietic progenitor cells has revealed that OS are a new class of inhibitors of HSPC proliferation of potential relevance in vivo and in vitro.
395

Design of high performance RFID systems for metallic item identification.

Ng, Mun Leng January 2008 (has links)
Although the origins of Radio Frequency Identification (RFID) technology can be traced back for many years, it is only recently that RFID has experienced rapid growth. That growth is mainly due to the increasing application of this technology in various supply chains. The widening of the implementation of RFID technology in supply chains has posed many challenges and one of the biggest is the degradation of the RFID system performance when tagging metallic objects, or when the RFID system operates in a metallic environment. This thesis focuses on tackling the issue of having metallic objects in an Ultra High Frequency (UHF) RFID system. The work presented in this thesis contributes to the research on UHF RFID systems involving metallic objects in several ways: (a) the development of novel RFID tags that range from a simple tag for general applications to tags suitable for metallic object identification; (b) the tag designs target the criteria of minimal tag size and cost to embrace the vision of item level tagging; and (c) the analysis of the performance (through theoretical predictions and practical measurements) of an RFID tag near metallic structures of various shapes and sizes. The early part of this thesis provides a brief introduction to RFID and reviews the background information related to metallic object identification for UHF RFID systems. The process of designing a basic tag, and additional information and work done related to the process, are outlined in the early part of this thesis. As part of this fundamental research process, and before proceeding to the designing of tags specifically for metallic objects, a small and low cost RFID tag for general applications was developed. Details of the design of this tag, with the application of this tag for animal identification, are presented. In the later parts of the work, different tag design approaches were explored and this has generated three rather different RFID tags suitable for attaching to metallic objects. The aim of this research is not just to design tags for metallic objects but also to tackle the constraints of having tags that are small in size, cost effective and suited in size to some familiar objects. Hence, in the later part of this research, the work took a step further where one of the three tags designed for metallic objects addressed the challenge of identifying individual small metallic beverage cans. RFID involves tagging of different types of objects and a tag may be required to be located in a depression of a metallic object. In the final part of this research, the read range performance of one of the RFID tags designed for metallic objects was analysed when the tag was located in metallic depressions of various shapes and sizes. The analysis was performed from a combination of theoretical calculation and simulation perspectives, and also through practical real-life measurements. Metallic objects are very common around us. Their presence is unavoidable and so to identify them, having the appropriate RFID tags suitable for operation on metallic surfaces is essential. Frequently the tags must be small in size and low in cost to allow identification at item level of individual small metallic objects. Understanding and being aware of the potential effects of metallic structures of various shapes and sizes on the tag performance is thus important. The research in this thesis into all the above can bring the industry further towards full deployment of RFID down to item level tagging. / Thesis (Ph.D.) - University of Adelaide, School of Electrical and Electronic Engineering, 2008
396

Effective Techniques for Indonesian Text Retrieval

Asian, Jelita, jelitayang@gmail.com January 2007 (has links)
The Web is a vast repository of data, and information on almost any subject can be found with the aid of search engines. Although the Web is international, the majority of research on finding of information has a focus on languages such as English and Chinese. In this thesis, we investigate information retrieval techniques for Indonesian. Although Indonesia is the fourth most populous country in the world, little attention has been given to search of Indonesian documents. Stemming is the process of reducing morphological variants of a word to a common stem form. Previous research has shown that stemming is language-dependent. Although several stemming algorithms have been proposed for Indonesian, there is no consensus on which gives better performance. We empirically explore these algorithms, showing that even the best algorithm still has scope for improvement. We propose novel extensions to this algorithm and develop a new Indonesian stemmer, and show that these can improve stemming correctness by up to three percentage points; our approach makes less than one error in thirty-eight words. We propose a range of techniques to enhance the performance of Indonesian information retrieval. These techniques include: stopping; sub-word tokenisation; and identification of proper nouns; and modifications to existing similarity functions. Our experiments show that many of these techniques can increase retrieval performance, with the highest increase achieved when we use grams of size five to tokenise words. We also present an effective method for identifying the language of a document; this allows various information retrieval techniques to be applied selectively depending on the language of target documents. We also address the problem of automatic creation of parallel corpora --- collections of documents that are the direct translations of each other --- which are essential for cross-lingual information retrieval tasks. Well-curated parallel corpora are rare, and for many languages, such as Indonesian, do not exist at all. We describe algorithms that we have developed to automatically identify parallel documents for Indonesian and English. Unlike most current approaches, which consider only the context and structure of the documents, our approach is based on the document content itself. Our algorithms do not make any prior assumptions about the documents, and are based on the Needleman-Wunsch algorithm for global alignment of protein sequences. Our approach works well in identifying Indonesian-English parallel documents, especially when no translation is performed. It can increase the separation value, a measure to discriminate good matches of parallel documents from bad matches, by approximately ten percentage points. We also investigate the applicability of our identification algorithms for other languages that use the Latin alphabet. Our experiments show that, with minor modifications, our alignment methods are effective for English-French, English-German, and French-German corpora, especially when the documents are not translated. Our technique can increase the separation value for the European corpus by up to twenty-eight percentage points. Together, these results provide a substantial advance in understanding techniques that can be applied for effective Indonesian text retrieval.
397

Role of fatty acid techniques in studying AM fungi / Rajni Madan.

Madan, Rajni January 2002 (has links)
"November 2002" / Includes bibliographical references (leaves 128-153) / xviii, 153 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil and Water, 2002
398

Exploring the use of human metrology for biometric recognition

Burri, Nikhil Mallikarjun Reddy. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 58 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 55-58).
399

Studies on weed risk assessment

Smith, Carey. January 1999 (has links) (PDF)
Bibliography: leaves 124-136. This thesis gives an overview of factors used in weed risk assessments and explores the disparity between the measured high accuracy rate of the weed risk assessment system (WRA) as implemented in Australia and the pessimistic assessments of some workers about the possibility of predicting the weed potential of plant species imported in the future. The accuracy of the WRA may not be as high as previously thought, and it varies with weed definition and taxonomic groups. Cluster analysis and comparative analysis by independent contrasts were employed to determine the value of individual biological and ecological questions on the WRA questionnaire. Results showed that some WRA questions could be deleted from the questionnaire and the scores for others weighted differently. The WRA is not a reliable predictor of weeds when it is considered in the context of the base-rate probability of an introduced plant becoming weedy in Australia. As a result a far greater number on non-weeds will be placed on the prohibited imported list than was initially expected.
400

Arbuscular mycorrhizal community in a permanent pasture and development of species-specific primers for detection and quantification of two AM fungi

Antoniolli, Zaida Inês. January 1999 (has links) (PDF)
Bibliography: leaves 138-160. The 152 species of mycorrhizal fungi can be difficult to identify and quantify because the taxonomy of these fungi is based on the description of spores, which is time consuming, requires considerable expertise and cannot be assumed to reflect the situation within the root. Few attempts have been made to identify the species which are present in roots. Several approaches have been identified in previous work and the development of sensitive molecular methods for identification and quantification of two species of arbuscular mycorrhizal (AM) fungi are described in this study. Mycorrhizal fungal communities were sampled in both natural and agricultural ecosystems at two sites in South Australia. The combination of spore identification from trap culture and field-collected soil promises to be an effective means to study diversity of AM fungi in a particular system. PCR primers for Glomus mosseae and Gigaspora margarita were designed from the internal transcribed spacer (ITS) sequences of field-collected spores, with the aim of providing tools for field diagnosis.

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