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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.
51

Aproximação facial forense: relação entre as estruturas ósseas e a porção inferior do nariz / Forensic facial approximation: relationship between the bone structure and the inferior portion of the nose

Raíssa Ananda Paim Strapasson 04 February 2016 (has links)
Este trabalho teve o propósito de avaliar a relação entre a cartilagem alar e a abertura piriforme a partir de imagens de tomografia computadorizada cone-beam e a relação do nariz com o padrão esquelético vertical da face. A pesquisa foi realizada com 96 imagens de indivíduos de ambos os sexos (49 masculino e 47 feminino), com idades entre 18 e 65 anos classificados de acordo com sua tipologia facial. Para a realização das marcações e mensurações de interesse foi utilizado o software OsiriX. A tipologia facial foi acessada através de três metodologias: índice facial, ângulo goníaco e proporção entre as alturas faciais. No corte axial da imagem de tomografia computadorizada, foram aferidas quatro grandezas lineares: largura do nariz externo, distância entre as inserções alares, extensão da base da abertura piriforme e máxima largura da abertura piriforme. Todas as grandezas foram mensuradas por dois examinadores em concordância. A análise dos resultados obtidos mostrou que há correlação entre as larguras do nariz externo e da abertura piriforme e entre a base da cavidade nasal e a distância entre as inserções alares. A largura da abertura piriforme aumenta proporcionalmente mais que a do nariz. Além disso, a tipologia facial longa associa-se à largura nasal. / The aim of this study was to evaluate the relationship between the alar cartilage and the pyriform aperture using cone-beam computed tomography (CT) imaging, and the relationship between the morphology of the nose and the vertical skeletal pattern of the face. 96 images of subjects (49 male and 47 female), aged 18-65 years classified according to the vertical skeletal pattern of the face were used in this study. The OsiriX software was used to measure the structures of interest. The facial pattern was obtained according to three techniques: facial index, gonial angle, and facial proportions. From an axial section of the CT imaging, four measurements were performed: nasal width, distance between the alar insertions, extension of the base of the pyriform aperture and width of the pyriform aperture. All measurements were obtained by two calibrated examiners. There is correlation between the nasal width and the breadth of the pyriform aperture, and between the base of the nasal cavity and the distance between the alar insertions. The width of the pyriform aperture proportionally increases more than the nasal breadth. Furthermore, the long face type is associated with nasal width.
52

Microbial Processes and Volatile Metabolites in Cheese Detection of Bacteria Using an Electronic Nose

Westling, Magnus January 2015 (has links)
Cheese is a fermented product in which bacteria contribute to different flavours and textures. In order to understand the microbial processes in cheese, it is necessary to not only look at the genomic information in bacteria. The metabolome consists of a complete collection of metabolites in a biological sample. These metabolites are small molecules with a Mr >1.5 kDa, including flavour compounds. During the ripening process of cheese, many microbiological and biochemical changes occur that give cheese a diversity of textures and flavours. Proteins that go through proteolysis and amino acid catabolism are of great importance in the development of flavour in cheese, regardless of variety. Even though techniques for measurements of metabolites have existed for a long time, there are some unique challenges by analysing of several metabolites in parallel in a biological sample that promotes different metabolic pathways. Metabolic fingerprinting is the most common approach used in metabolomics, which is based on statistical analysis that through algorithms presents differences between samples. The electronic nose is able to identify the sum of volatile metabolites in a food, which is unlike the gas chromatograph that identifies individual metabolites. The aim of this review is to evaluate the use of metabolomics of selected Enterobacteriaceae together with electronic nose technology in order to analyse possible patterns of volatile metabolites produced in soft cheese. By this we hope to evaluate potential application of this approach in food quality control and microbial contamination screening. The pilot study was done together with the center for AASS, Örebro University where bacteria were analysed using the electronic nose NST3320. The study showed that it is possible to discriminate between Enterobacteriaceae, Staphylococcus aureus and cheese-associated bacteria, but also between the Enterobacteriaceae species Escherichia coli, Hafnia alvei and Klebsiella neumoniae. It is important to consider the gas sensors gradually lose their ability to detect substances after continual use, in which they need to be replaced with new gas sensors. Further, data processing requires special knowledge and can be hard to handle if the expertise is lacking. We believe that there is evidence that metabolomics together with the electronic nose have future prospects in terms of quality control and microbial contamination screening.
53

Microbial processes and volatile metabolites in cheese : detection of bacteria using an electronic nose

Westling, Magnus January 2015 (has links)
Cheese is a fermented product in which bacteria contribute to different flavours and textures. In order to understand the microbial processes in cheese, it is necessary to not only look at the genomic information in bacteria. The metabolome consists of a complete collection of metabolites in a biological sample. These metabolites are small molecules with a Mr >1.5 kDa, including flavour compounds. During the ripening process of cheese, many microbiological and biochemical changes occur that give cheese a diversity of textures and flavours. Proteins that go through proteolysis and amino acid catabolism are of great importance in the development of flavour in cheese, regardless of variety. Even though techniques for measurements of metabolites have existed for a long time, there are some unique challenges by analysing of several metabolites in parallel in a biological sample that promotes different metabolic pathways. Metabolic fingerprinting is the most common approach used in metabolomics, which is based on statistical analysis that through algorithms presents differences between samples. The electronic nose is able to identify the sum of volatile metabolites in a food, which is unlike the gas chromatograph that identifies individual metabolites. The aim of this review is to evaluate the use of metabolomics of selected Enterobacteriaceae together with electronic nose technology in order to analyse possible patterns of volatile metabolites produced in soft cheese. By this we hope to evaluate potential application of this approach in food quality control and microbial contamination screening. The pilot study was done together with the center for AASS, Örebro University where bacteria were analysed using the electronic nose NST3320. The study showed that it is possible to discriminate between Enterobacteriaceae, Staphylococcus aureus and cheese-associated bacteria, but also between the Enterobacteriaceae species Escherichia coli, Hafnia alvei and Klebsiella pneumoniae. It is important to consider the gas sensors gradually lose their ability to detect substances after continual use, in which they need to be replaced with new gas sensors. Further, data processing requires special knowledge and can be hard to handle if the expertise is lacking. We believe that there is evidence that metabolomics together with the electronic nose have future prospects in terms of quality control and microbial contamination screening.
54

Návrh podvozku malého dvoumístného letounu / Landing gear design of two-seat airplane

Čavojský, Tomáš January 2021 (has links)
This diploma thesis deals with the landing gear design of the small two-seat aircraft. The introduction focuses on the conceptual gear design and shock absorber computational dynamic characteristic model. The practical part is focused on the landing gear construction according to the selected parameters based on the conceptual and computational model. The diploma thesis ends with strength calculations and production documentation.
55

Bat Population Monitoring in National Parks of The Great Lakes Region and Evaluation of Bat Acoustic Analysis Software

Goodwin, Katy Rebecca January 2019 (has links)
North American bats face multiple threats, prompting an increase in bat research and conservation efforts in recent decades. Researchers often use acoustic monitoring, which entails recording bats? echolocation calls and subsequently identifying them to species, typically using automated software. Chapter 1 describes an acoustic monitoring program at eight U.S. national parks that aims to assess changes in bat populations over time. Data collected in 2016-2017 showed that activity levels of the little brown bat (Myotis lucifigus) decreased significantly while other species remained stable. Little brown bats have undergone similar population declines elsewhere due to the disease white-nose syndrome. Chapter 2 investigates whether different versions of bat call identification software are comparable to each other and how accurate they are. For the two software programs tested, agreement among versions was variable and species-dependent. Furthermore, newer versions were more conservative in assigning identifications, though not, on average, more accurate.
56

Craniofacial pattern profile analysis of individuals with frontonasal malformation

Hiester, John David, 1964- January 1994 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Frontonasal malformation, FNM, was first described by Hoppe in 1859. FNM is an anomaly that is characterized by ocular hypertelorism, broad nasal root, lack of a nasal tip, V-shaped hair, prolongation onto the forehead (widow's peak), anterior cranium bifidum occultum, median facial cleft affecting the nose, upper lip, and/or palate, and uni- or bilateral clefting of the ala nasi. The anomalies noted in FNM may be explained as a single malformation. If the nasal capsule fails to develop properly, the primitive brain vesicle fills the space normally occupied by the capsule, thus producing anterior cranium bifidum occultum, an arrest in the positioning of the eyes, and a lack of formation of the nasal tip. The condition presents clinically with variable expressions as sporadic cases and infrequently in familial cases. The present study is the first attempting to quantify and characterize FNM via anatomic radiographic measurements. The lateral (LA) and posterior-anterior (PA) cephalometric radiographs of twenty-four individuals, both sporadic and familial, with FNM were analyzed for comparison of linear and angular measurements with previously published data of a "normal," i.e. unaffected, population standard. Usual and customary cephalometric points were identified and located, then digitized into the computer. Twenty-nine measurements included the previously diagnosed anomalous features of hypertelorism, medial nasal cavity, and palatal shelves, as well as other facial features. The radiographs of individuals with FNM have anatomic features that are unusual and distinct to the specific malformation. The data from this research suggest that patients with FNM, regardless of a genetic or sporadic predisposition, have a midface deficiency in height and depth, an increased interorbital width with possible increased orbital socket width, and a longer zygomatic buttress. Also, the familial cases tend to have a flatter cranial base than the sporadic cases. Furthermore, the familial patients might be a different type of FNM since this subgroup shows narrower zygomatic widths. The patients with surgical procedures demonstrated improvement different from the growth of those patients who did not have surgery. The hypothesis that the facies of a patient with frontonasal malformation is different from the "normal" control population is supported by this research. The differences between the familial and sporadic patients tend to support the general theory that genetic predisposition is less severe than FNM that occurs randomly.
57

Chemosensory Evaluation of Training and Oxidative Stress in Long Distance Runners

Whysong, Christan Yvonne 28 May 2014 (has links)
Athletes complete a balance of training loads and rest periods, risking overtraining when this balance favors excessive training. Diagnostic biomarkers have been suggested but a clear diagnostic method is not available. This preliminary study's objective was to use data standardization to improve an electronic nose's (enose) discrimination model for athletes' breathprints after cumulative and acute training loads. Collegiate long distance runners were observed throughout competitive training seasons. Prolonged training effects were observed through Profile of Mood States (POMS) surveys and blood and breath samples collected at the beginning (Pre-Study) and end of the training season (Post-Study). Immediate training effects were observed for one low (LI) and one high (HI) intensity acute training load. Subjects provided blood and breath samples before the LI (BSR) and HI (BLR), completed the training load, and provided blood and breath samples after each training load (ASR; ALR). Blood was analyzed for antioxidant enzymes (catalase, glutathione peroxidase, and glutathione reductase). Breath samples were analyzed with a Cyranose® 320 (C320) enose. Age, gender, and training loads affected oxidative states, with the HI having more effect than the LI. Mood profiles indicated healthy and successful athletes. Neither POMS nor blood parameters suggested overtrained athletes. The C320 successfully discriminated between breathprints of athletes correlating to the training loads. Direct data standardization through carbon dioxide as a baseline sensor purge correctly classified 100 percent of the data through linear discriminant analysis (LDA). Indirect data standardization by subtracting Pre-Study data from the subsequent data classes (e.g. BSR) correctly classified 96 percent of the data. An LDA on the combined blood parameters correctly classified 61.9 percent of the data. The blood analyses required invasive sample collections and involved procedures that took a long time (hours). In comparison, the best C320 model correctly classified 96 percent of the data and required less invasive sample collections, simple analysis, and short result times (minutes). Evidence suggested the C320 will provide a simple and noninvasive method for clinically diagnosing the onset of overtraining. The unit is small, handheld, rapid, and noninvasive so it could also be used on- site to provide immediate feedback for training optimization. / Ph. D.
58

Chemosensory Evaluation of Training and Oxidative Stress in Long Distance Runners

Whysong, Christan 23 November 2009 (has links)
Athletic performance is improved by increasing training loads but it is difficult to determine an athlete's response to a training load and the amount of stress incurred. This makes athletes susceptible to overtraining, leading to decreased performance levels, due to physical exhaustion and oxidative stress. Past studies have observed a myriad of biomarkers without conclusively identifying a clinically specific marker for overtraining due to oxidative stress. These methods require invasive testing and lengthy result times, making real-time adjustments of training programs to prevent overtraining difficult. The use of an electronic nose (enose) as a non-invasive evaluation tool will provide immediate feedback on training stress, allowing for real-time training adjustments for performance optimization. Two long distance runners (one male and one female) completed a pilot study. Both performed a short run and the female performed a long run. Blood samples were collected from each athlete before and after each run and analyzed for catalase and GPx activity. Breath samples were also collected before and after each run and analyzed by an enose. Multivariate analyses of combined blood data yielded better results than individual analyses. Although data was limited for this pilot study, canonical discriminant analyses (CDA) showed separation between before and after run and between short and long run breath samples. Cross validations also found up to a 77.8 percent prediction accuracy for the enose. Results indicate an enose is feasible for detecting changes in the breath occurring after physically demanding exercise perhaps due to oxidative stress incurred during the exercise. / Master of Science
59

Discriminating the Effects of Vineyard Management Practices on Grape and Wine Volatiles from Cabernet Franc and Merlot Grape Varieties Using Electronic Nose Systems

Devarajan, Yamuna Swetha 13 October 2009 (has links)
Vineyard management practices are known to affect fruit composition and resultant wines, in part, by altering fruit volatiles. Methods currently used to evaluate the impact of vineyard practices on grape/wine composition include measuring physico-chemistry indices and performing wine sensory analyses. These activities are both time-consuming and destructive. Two electronic nose (ENose) systems: a hand-held conducting polymer-based and a portable surface acoustic wave-based systems were investigated as grape monitoring tools. Vineyard treatments included the effect of canopy side (East vs. West and North vs. South), cluster thinning (unthinned, 1 cluster/shoot, and 1 & 2 cluster/shoot) and ethanol spray (5% v/v) on Cabernet franc, Merlot and both varieties respectively. ENose data were obtained in the field (over two growing seasons for canopy side and in 2008 for cluster thinning and ethanol spray) and laboratory (2007 for canopy side), across different sampling dates and compared with nine-grape/eight-wine chemistry assays, GC/MS (cluster thinning) and wine aroma sensory evaluations (triangular difference testing). ENose results demonstrated 100% significant differences between all Cabernet franc and Merlot treatments. Grape/wine chemistry indices, for both Cabernet franc and Merlot, did not differ among treatments (except ethanol treatment) across sampling dates or growing seasons and vineyard management practices. Wine aroma sensory evaluations demonstrated only limited differences (3 out of 8 comparisons: East vs. West, 1 cluster/shoot vs. 1 & 2 clusters/shoot and 1 cluster/shoot and 1 & 2 clusters/shoot). The high level of discrimination by ENose systems may provide opportunities to enhance the understanding of vineyard management activities. / Master of Science in Life Sciences
60

Chemosensory Evaluation of Prostate Cancer Cells

Martinez, Rebecca L. 14 January 2011 (has links)
Prostate cancer is the most commonly diagnosed disease and second most commonly caused death among men in America. Although much controversy surrounds the current methods of detection, PSA test and biopsy, no new methods have been approved as an effective method of detection. Biomarkers and non-invasive means of detection are being investigated everyday in hopes of discovering new information that could be of use in the prostate cancer field. One such non-invasive technology is the use of an electronic nose. The electronic nose technology has been utilized in the agricultural, food, biomedical, and environmental. The objective of this current study is to determine the effectiveness of the electronic nose to discriminate between prostate cancer cells (DU-145 and PC-3) and non-tumor forming cells from the urinary tract (SVHUC). Specific factors that will be investigated are incubation period and cell population. For all three cell lines, two cell populations of 75,000 and 150,000 cells were cultured and tested after 2, 8, 12, and 24 hours using a conducting polymer based hand-held electronic nose. Multivariate analysis was performed on the data and determined that the greatest discrimination between incubation periods was between 2 hours of incubation and the remaining periods of 8, 12, and 24 hour periods. This presents the idea that by 8 hours, ample volatiles were produced to be detected by the electronic nose. Additionally, when compared to one another, all three cell lines showed distinct differences. The cell lines most closely related were PC-3 and DU-145, the prostate cancer cell lines. However some variation was seen between these cell lines, which may be attributed to the presence of PSA in PC-3 cells or other factors affecting prostate cancer patients. Finally, PCA plots clearly illustrated that after 2 hours of incubation, sufficient volatiles were produced to allow the electronic nose to clearly discriminate the three cell lines from one another, demonstrating the importance of incubation period on successful discrimination. Based on the findings that the electronic nose was effective at discriminating the three cell lines, testing was completed to determine if cell population or cell maturity had the greatest effect on discrimination. The cell lines were cultured and tested immediately using an initial cell population of the highest cell population observed after a 72 hour incubation period. The results concluded that when the cell lines were tested immediately after culturing, the Cyranose was able to detect the individual cell lines in culture while also determining a range of detection for each cell line. The range of detection for DU-145 was found to be 26,200 to 262,000 cells based on interclass m-distances of 6.829-9.170 for cell populations lower than 26,200. A range of detection of 51,400 to 514,000 cells was concluded for PC-3 cells based on interclass m-distances of 5.690-7.400 for cell populations lower than 51,400. Finally, the results showed a range of detection of 19,000 to 190,000 cells for SVHUC based on interclass m-distances of 5.520-9.076 for cell populations lower than 19,000. However, when attempting to discriminate the three cell lines against one another immediately after culture, the electronic nose was unable to make clear distinctions between the three cell lines. When testing cancerous and non-cancerous cells, incubation period of the cells should be the only factor considered. It is evident that the cells need time to metabolize and produce volatiles so that the electronic nose can clearly distinguish these cells from one another in culture. / Master of Science

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