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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.
61

Electronic Nose Evaluation of Grape Maturity

Athamneh, Ahmad I. 01 November 2006 (has links)
Grape maturity is a critical attribute impacting potential wine quality. Maturity evaluation is difficult due to the many interrelated factors that impact physicochemical changes and limitations in the understanding of these factors. Current methods of assessing grape maturity are destructive, expensive, time consuming, subjective, and do not always strongly correlated to potential wine quality. This study evaluated the applicability of a conducting polymer-based electronic nose to monitor grape maturity by analyzing headspace volatiles. In the first part of the study, system and experimental parameters affecting the electronic nose operation were investigated to optimize detection of wine grape aroma. In the second part, the ability of an electronic nose to classify Cabernet Sauvignon (Vitis vinifera L.) grapes based on maturity was investigated. Maturity of samples collected at different weeks post-bloom was evaluated by measuring berry weight, pH, Brix, titratable acidity, total phenols, color intensity, hue, total anthocyanins, and total and phenol-free glycosides. Results were compared, using discriminant and canonical discriminant analysis, with analysis of headspace volatiles via the hand-held electronic nose. The electronic nose was able to determine the difference between the sample groups. Field measurements demonstrated the potential for the electronic nose as a rapid, non-destructive tool for evaluating grape maturity. / Master of Science
62

Discrimination of Retained Solvent Levels in Printed Food-Packaging Using Electronic Nose Systems

Van Deventer, David 03 October 2001 (has links)
The expanding role of electronic nose instrumentation, as a quality-monitoring tool for food-packaging materials, is examined and reviewed. The food industry is interested in determining the applicability of using an electronic nose for odor analysis of retained printing solvent levels in packaging. Three electronic nose systems were optimized for this application and their performance assessed. These include the FOX 3000, the Cyranose 320, and the QMB6. Response surface methodology was used to generate 2nd order models of sensor response as a function of system and experimental parameters for the three electronic nose systems. Forty-seven of 50 sensor models generated were found to be significant at an a-level of 0.05. Optimum settings, that allowed adequate signals to be obtained for the full range of examined retained solvents levels, were selected for the remaining work using these models. Performance analyses of these systems, which use three leading sensor technologies, showed that the conducting polymer sensor technology demonstrated the most discriminatory power. All three technologies proved able to discriminate among different levels of retained solvents. Each complete electronic nose system was also able to discriminate between assorted packaging having either conforming or non-conforming levels of retained solvents. Each system correctly identified 100% of unknown samples. Sensor technology had a greater effect on performance than the number of sensors used. Based on discriminatory power and practical features, the FOX 3000 and the Cyranose 320 were superior. The results indicate that electronic nose instrumentation can be used as a complimentary discriminatory tool in quality control. / Master of Science
63

Non-Destructive Evaluation of Apple Maturity Using an Electronic Nose System

Pathange, Lakshmi Prasad 07 May 2003 (has links)
The apple growers and packaging houses are interested in methods that can evaluate the quality of apples non-destructively. Harvested fruits are a mixture of immature, mature, and over mature fruits, thereby posing a great problem in deciding their end use and storage time. It is expected that the technique developed from the present project could be effectively used to classify the harvested fruit into immature, mature and over mature apples, rapidly and non-destructively. It would also help the growers to predict the optimum dates to harvest the fruits. York and Gala were the varieties of apples that were used in this study and were obtained from Virginia Tech College of Agriculture and Life Sciences Kentland Farm. Apples were harvested at different times resulting in different maturity groups (immature, mature and ripe). Gala apples were harvested on three dates with an interval of 10 days, while York apples were harvested on four dates with an interval of 14 days. They were stored at 0oC until sampled. For each harvest date, the experiments were conducted in two sets (10 each) on two consecutive days. First the ethylene levels were measured, followed by gas chromatograph and electronic nose. Then the maturity indices were measured. Three maturity indices, starch index, firmness and soluble solids were used as the three variables for the statistical analysis to identify and categorize the fruits into three maturity categories referred as immature, mature and over mature fruits. Apples were also categorized into three maturity groups based on the emanation levels of the aroma compounds evolved from the fruits. Then electronic nose sensor responses were categorized into the above maturity categories, and their effectiveness was determined using a statistical procedure called Discriminant Analysis (DA). From the DA cross validation results the correct classification percentage for Gala and York apples into maturity groups was 95%. The Electronic nose sensor's effectiveness to categorize the same observations based on sensor responses in to the above classified maturity categories was 83% correct in case Gala apples and 69% for York apples. The EN sensors response data were analyzed by the EN system software and the correct classification percentage for Gala was 83% and for York was 81%. Aroma-based categorization for Gala apples was 100% correct, while the electronic nose for the same analysis was 80%. Based on the three physical parameters, an objective evaluation of maturity could be accomplished. Principal Component Analysis, Canonical Discriminant Analysis and DA results demonstrated that the electronic nose could be used to classify apples into three identified maturity-based groups. The EN sensors (Gala apples), could also classify the apples into aroma-based categories. Thus, it can be concluded that the EN system holds promise as non-destructive evaluation technique to determine the maturity of an apple. / Master of Science
64

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 14 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
65

Estudo sobre o nariz para reconstrução facial forense / Study of the nose for forensic facial reconstruction

Strapasson, Raíssa Ananda Paim 29 March 2019 (has links)
Esta tese é composta por três capítulos. O primeiro capítulo teve por objetivo analisar quais as técnicas de reconstrução nasal mais consistentes em contexto forense através de uma revisão sistemática da literatura. No total, existem 15 métodos de reconstrução nasal descritos na literatura. Para localizar a ponta do nariz e estimar a projeção nasal em indivíduos brasileiros, o método que se demonstrou, em meta-análise, o mais apropriado foi o que considera que o ângulo (ponto Pronasale) formado pelas retas que partem dos pontos Rhinion e Prosthion possui valor aproximado de 90º. O capítulo II teve como propósito testar, mediante análise de imagens tomográficas, o método desenvolvido em indivíduos brasileiros para estimar a localização da ponta do nariz em casos de reconstrução facial forense. De acordo com a técnica, o ângulo (ponta do nariz) formado pela união de retas traçadas a partir dos pontos Rhinion e Prosthion corresponde a 90º. O programa Horos® foi utilizado para analisar as imagens dos exames de tomografia computadorizada de feixe cônico. Os critérios de seleção da amostra foram semelhantes aos utilizados no trabalho que propõe o método, assim como as análises realizadas. Os resultados mostraram que o ângulo de interesse correspondeu em média a 96.5º. Esta diferença resultou em uma inacurácia de aproximadamente 3 mm da localização estimada da ponta do nariz em relação à sua localização real. Em termos práticos, esta diferença não impede o reconhecimento facial. O terceiro capítulo teve o propósito de testar o método proposto para estimar a largura nasal de indivíduos brasileiros em reconstrução facial forense, além de determinar parâmetros em tecido duro para estimar a largura nasal e verificar relações entre o tipo facial e a morfologia do perfil nasal. A amostra foi composta por 246 imagens de tomografia computadorizada de feixe cônico (feminino: 183; masculino: 63). O programa Horos® foi utilizado. As análises em tecido duro foram realizadas na visualização de reconstrução multiplanar com projeção de máxima intensidade igual a zero, e a análise do perfil nasal foi realizada em tecido mole na ferramenta de visualização de superfícies. Os resultados mostram que o método proposto para estimar a largura nasal em brasileiros apresentou uma inacurácia de aproximadamente 1 mm, fato que não interfere no reconhecimento facial. Não houve relação de proporção direta entre a largura do nariz e a abertura piriforme, nem entre a largura do nariz e a distância intercanina, mesmo quando foram consideradas variáveis como sexo, idade e tipo facial. O biótipo facial longo apresentou relação moderada com o perfil nasal reto (r=0.037). / This thesis contains three chapters. The first chapter aimed to conduct a systematic review to analyze what are the most consistent techniques of nasal reconstruction in a forensic context. There are fifteen nasal reconstruction methods described in the literature. To predict the Pronasale point and the nasal projection, the method that considers that the confluence between the lines traced from Rhinion and from Prosthion is an angle (Pronasale point) with a value of 90º presented good results when meta-analysis was performed. The aim of the second chapter was to test, trough CT images, the method developed on a sample of Brazilian subjects to predict the Pronasale point in forensic facial reconstruction. According to this technique, the union of the Rhinion and the Prosthion lines creates an 90º angle (Pronasale point). The software Horos® was used in order to perform the analysis on the cone-beam tomography images. The inclusion criteria of the sample were the same used by the primary study as well as the performed analysis. The results showed a mean value of 96.5º from the projection Pronasale and Rhinion. This difference results in an inaccuracy of approximate 3 mm of the Pronasale point and it is not impeditive for facial recognition of a familiar face. The third chapter aimed to test the method proposed to predict nasal length in Brazilian subjects, to determine hard tissue parameters to predict nasal length and to observe if there was any relation between facial pattern and nasal profile. The sample was composed by 246 cone beam computed tomography (183 female, 63 male). The software Horos® was used. The hard tissue analysis were performed on 3D multiplanar reconstruction with maximum intensity projection equal to zero, and the 3D surface rendering was used to verify the nasal profile in soft tissue. The proposed method to predict nasal length presented an inaccuracy of approximate 1 mm and it certainly does not influence facial recognition of familiar faces. There was no relation between nor nasal length and piriform aperture nor nasal length and intercanine distance even when sex, age and facial type were considered. The long facial type showed moderate relation with strength nasal profile (r=0.037).
66

Synchrony in adult male Atlantic Spotted Dolphins (Stenella frontalis) during aggression

Unknown Date (has links)
Synchrony between Atlantic spotted dolphins (Stenella frontalis) is crucial for successfully fending off bottlenose dolphins (Tursiops truncatus) during interspecies aggression. The present study examined synchrony in adult Atlantic spotted dolphins during aggressive encounters with bottlenose dolphins. Across group size, aggressive behavioral events increased preceding synchrony, peaked during synchrony, and decreased dramatically after synchrony. Although smaller groups (< 10 dolphins) became synchronous more frequently than larger groups (> 10 dolphins), larger groups remained synchronous longer; however, smaller groups exhibited more frequent aggressive behavioral events during synchrony, suggesting that additional aggressive behaviors may be necessary to compensate for the small group size, whereas larger groups may be able to rely on synchrony alone. Disorganized squawk bouts synchronized as physical synchrony began, but only if coupled with escalating aggressive behaviors. The synchrony during aggressive episodes observed in adult Atlantic spotted dolphins can be used as a baseline to determine the process of the development of this critical skill in juveniles. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
67

Infecção experimental por Salmonella enterica subspécie enterica sorotipo Panama e tentativa de transmissão naso-nasal em leitões desmamados /

Oliveira, Luís Guilherme. January 2008 (has links)
Orientador: Luiz Fernando de Oliveira e Silva Carvalho / Banca: Geraldo Camilo Alberton / Banca: Adolorata Aparecida Bianco Carvalho / Resumo: A transmissão pela via fecal-oral é considerada o mais importante meio de disseminação de Salmonella sp. entre os suínos. Foi comprovada que a transmissão de Salmonella sp. através do contato naso-nasal entre suínos pode ser viável. Porém, alguns experimentos não conseguiram demonstrar tal transmissão em determinados sorotipos de Salmonella enterica. Este ensaio teve como objetivo produzir infecção experimental de Salmonella enterica subsp. enterica sorotipo Panama e verificar a importância da via nasonasal na transmissão entre leitões desmamados. Seis leitões recém-desmamados foram adquiridos de granja previamente selecionada, livre de Salmonella sp. Análises bacteriológicas confirmaram que todos os animais estavam livres de contaminação por Salmonella sp. Utilizaram-se baias isoladoras que proporcionavam o contato naso-nasal e eliminavam a possibilidade de outras vias de transmissão e de contaminação externa. Três grupos foram formados: controle, sentinela e infectados. Os leitões do grupo controle e do grupo sentinela receberam, individualmente, por via oral, solução estéril, enquanto que leitões do grupo infectado receberam inóculo contendo 2,16 X 1010 UFC de Salmonella Panama. Foram alojados nos isoladores respectivos e retirados depois de 14 dias, período no qual amostras de fezes eram colhidas e avaliadas diariamente. Os animais foram necropsiados e amostras de tecidos colhidas. Realizaram-se testes bacteriológicos, ELISA e sorotipificação. Houve infecção sistêmica por Salmonella Panama nos animais do grupo infectado, porém os resultados revelaram não haver a transmissão pela via naso-nasal entre leitões desmamados, pois em nenhum momento o agente foi isolado dos animais sentinelas. / Abstract: The faecal-oral transmission is considering the most important route for transmission of Salmonella sp. between pigs. It has been proven that the Salmonella sp. transmission through the nose-to-nose contact among pigs can be viable. However, current data could not demonstrate such transmission in certain serovars of Salmonella enterica. This study aimed to produce experimental infection of Salmonella enterica serovars Panama and verifies the importance of the nose-to-nose contact in the transmission among weaned pigs. Six recently-weaned pigs were acquired from farm previously selected; free from Salmonella sp. Bacteriological analysis ruled out previous Salmonella sp contamination in all selected subjects. Isolations cabinets were used that provided the nose-to-nose contact and to eliminated the presence of other transmission routes and of outside contamination. Three groups were formed: control, sentinel and infected. The pigs of the control group and of the sentinel group, received, individually, orally sterile solution, while pigs of the infected group received solution containing 2,16 X 1010 CFU of Salmonella Panama. They were housed in the respective isolations cabinets and removed from it after 14 days, period in which samples of faeces were collected and submitted to daily analysis. The animals were necropsied and samples of tissues were collected. They were tested by bacteriological analysis, ELISA and serovars typification. There was systemic infection for Salmonella Panama in the animals of the infected group; however there was non transmission by nose-to-nose contact among weaned pigs, justifying the non isolation of the agent in the sentinel group at any moment. / Mestre
68

Infecção experimental por Salmonella enterica subspécie enterica sorotipo Panama e tentativa de transmissão naso-nasal em leitões desmamados

Oliveira, Luís Guilherme [UNESP] 19 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-19Bitstream added on 2014-06-13T19:50:57Z : No. of bitstreams: 1 oliveira_lg_me_jabo.pdf: 385808 bytes, checksum: 724ed5f57dfbaab664f6c58ba810c163 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A transmissão pela via fecal-oral é considerada o mais importante meio de disseminação de Salmonella sp. entre os suínos. Foi comprovada que a transmissão de Salmonella sp. através do contato naso-nasal entre suínos pode ser viável. Porém, alguns experimentos não conseguiram demonstrar tal transmissão em determinados sorotipos de Salmonella enterica. Este ensaio teve como objetivo produzir infecção experimental de Salmonella enterica subsp. enterica sorotipo Panama e verificar a importância da via nasonasal na transmissão entre leitões desmamados. Seis leitões recém-desmamados foram adquiridos de granja previamente selecionada, livre de Salmonella sp. Análises bacteriológicas confirmaram que todos os animais estavam livres de contaminação por Salmonella sp. Utilizaram-se baias isoladoras que proporcionavam o contato naso-nasal e eliminavam a possibilidade de outras vias de transmissão e de contaminação externa. Três grupos foram formados: controle, sentinela e infectados. Os leitões do grupo controle e do grupo sentinela receberam, individualmente, por via oral, solução estéril, enquanto que leitões do grupo infectado receberam inóculo contendo 2,16 X 1010 UFC de Salmonella Panama. Foram alojados nos isoladores respectivos e retirados depois de 14 dias, período no qual amostras de fezes eram colhidas e avaliadas diariamente. Os animais foram necropsiados e amostras de tecidos colhidas. Realizaram-se testes bacteriológicos, ELISA e sorotipificação. Houve infecção sistêmica por Salmonella Panama nos animais do grupo infectado, porém os resultados revelaram não haver a transmissão pela via naso-nasal entre leitões desmamados, pois em nenhum momento o agente foi isolado dos animais sentinelas. / The faecal-oral transmission is considering the most important route for transmission of Salmonella sp. between pigs. It has been proven that the Salmonella sp. transmission through the nose-to-nose contact among pigs can be viable. However, current data could not demonstrate such transmission in certain serovars of Salmonella enterica. This study aimed to produce experimental infection of Salmonella enterica serovars Panama and verifies the importance of the nose-to-nose contact in the transmission among weaned pigs. Six recently-weaned pigs were acquired from farm previously selected; free from Salmonella sp. Bacteriological analysis ruled out previous Salmonella sp contamination in all selected subjects. Isolations cabinets were used that provided the nose-to-nose contact and to eliminated the presence of other transmission routes and of outside contamination. Three groups were formed: control, sentinel and infected. The pigs of the control group and of the sentinel group, received, individually, orally sterile solution, while pigs of the infected group received solution containing 2,16 X 1010 CFU of Salmonella Panama. They were housed in the respective isolations cabinets and removed from it after 14 days, period in which samples of faeces were collected and submitted to daily analysis. The animals were necropsied and samples of tissues were collected. They were tested by bacteriological analysis, ELISA and serovars typification. There was systemic infection for Salmonella Panama in the animals of the infected group; however there was non transmission by nose-to-nose contact among weaned pigs, justifying the non isolation of the agent in the sentinel group at any moment.
69

Infecção experimental por Salmonella enterica subspécie enterica sorotipo Panama e tentativa de transmissão área em leitões desmamados

Masson, Guido Carlos Iselda Hermans [UNESP] 19 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-19Bitstream added on 2014-06-13T18:51:21Z : No. of bitstreams: 1 masson_gcih_me_jabo.pdf: 359070 bytes, checksum: f5f42c27d6d60c4767c1043aea46bed5 (MD5) / O objetivo deste trabalho foi avaliar infecção por Salmonella enterica subespécie enterica sorotipo Panama e a possibilidade de transmissão aérea de entre leitões desmamados. Seis leitões recém-desmamados e sadios foram igualmente distribuídos na formação dos três grupos experimentais – o grupocontrole, o grupo infectado e o grupo-sentinela. Os animais foram alojados dois a dois em três câmaras de isolamento especialmente projetadas para o estudo, que garantiam não apenas que os animais fossem mantidos completamente isentos de contacto com o ambiente externo mas que o fluxo de ar unidirecional, no sentido animais-controle - animais infectados – animais-sentinela, fosse a única maneira de disseminação do agente. Salmonella Panama com resistência induzida ao ácido nalidíxico (Salmonella PanamaNal+) foi utilizada na preparação do inóculo. Análises microbiológicas de suabes retais dos animais foram realizadas diariamente em todos os animais durante os 14 dias subseqüentes à inoculação, após o que os animais foram eutanasiados e necropsiados, visando análises microbiológicas de amostras de órgãos internos. As análises bacteriológicas iniciaram-se pelo pré-enriquecimento das amostras, em caldo GN-Hajna para as amostras de fezes e a água peptonada tamponada para os órgãos internos. Prosseguiram pelo enriquecimento em caldo Rappaport-Vassiliadis e em Tetrationato Müller Kaufmann para então serem semeadas nos ágares xilose lisina tergitol 4 (XLT4) e verde-brilhante modificado, ambos suplementados com ácido nalidíxico. Colônias características foram submetidas às provas bioquímicas, em ágar tríplice açúcar ferro (TSI) e ágar ferro lisina (LIA) e posteriormente a avaliação sorológica. Amostras de sangue foram colhidas de todos os animais e, submetidas ao teste ELISA... / The aim of this study was to evaluate the experimental infection wich Salmonella serotype Panama and the airborne transmission of among weaned piglets. Six weaned piglets were used and distributed in three groups of animals - group 1 (control), group 2 (infected) and group 3 (sentinels). All animals were housed in three stainless-steel glass isolation cabinets connected by unidirectional airflow air ducts. Animals didn't have contact with the external environment, guaranteeing that airflow was the unique way of the agent's spread. An induced nalidixic acid resistant strain of Salmonella Panama (Salmonella Panama Nal+) were used to induce infection in one of the groups. Bacteriological analyses of rectal swabs were implemented daily within 14 days after inoculation. For bacteriological exams of internal organs animals were euthanized and necropsied. A pre-enrichment in broth GN-Hajna for the fecal samples and in buffered peptone water for the internal organs samples were conducted. Subsequently, samples were transferred to Rappaport-Vassiliadis and Tetrationato Müller Kaufmann. The samples were transferred to the agar xylose-lysine-tergitol 4 (XLT4) and to a modified brilliant green media, both supplemented with nalidixic acid. Characteristic colonies were submitted to the biochemical tests triple sugar iron agar (TSI) and lysine iron agar (LIA) and later to the serological prove. Samples of blood were taken twice - before Salmonella inoculation and before euthanasia of the piglets. Sera was submitted to the ELISA test. Results showed a Salmonella systemic infection in the inoculated animals (infected group), but there were no evidence of Salmonella transmission to the sentinel group.
70

Experimental Study Of Side Force Control On Slender Cones At High Angles Of Attack

Rajan Kuamr, * 04 1900 (has links) (PDF)
No description available.

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