Note: / The aim of this dissertation was 10 investigate if and how emotional arousalinfluences odor memory. I conducted three studies , one of which invo lved pat ients withresect ion from the medial tcmporal lobc including the amygd ala (MTLR). In the first experiment of Study 1, participants showed better memory for odo rs rated as being more emotionally arousing than tor odors rated as less arousing. / Cette dissertation avail pour objectif d'etudier si, de quelle maniere. L'eveil emotionnel influence la memoire olfactive. J'ai effectue trois etudes, dont une impliquant des patients ayant subi une resection du lobe temporal median inc1uant l'amygdalc (MTLR). Dans la premiere experience de l'etude 1, la reconnaissance des odeurs plus emotionnellement eveillantes a ete superieure a celle des odeurs moins eveillantes.

Thesis (Ph.D.)--Tufts University, 2003. / Adviser: David R. Walt. Submitted to the Dept. of Chemistry. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Note:

Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2003. / Vita. Includes bibliographical references.

Thesis (M.Sc. (Hons)) -- University of Western Sydney, 2004. / "This thesis was submitted in fulfilment of the requirements for the degree of Master of Science (Hons) in the Centre for Advanced Food Research, University of Western Sydney, June 2004" Includes bibliography.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 143-165). Also available in electronic version.

Thesis (MSc)--Stellenbosch University, 1967. / ENGLISH ABSTRACT: no abstract available / AFRIKAANSE OPSOMMING: geen opsomming

Heat treated orange juice, both pasteurized and concentrate, are being increasingly consumed in the U.S. Orange juice is primarily heat treated to increase its shelf life, by curbing the growth of microorganisms; and to inactivate pectin methylesterase, which demethylates pectin and leads to cloud loss in the juice. However, because of heat processing, orange juice undergoes undesirable flavor changes that decrease its acceptability to consumers. The objectives of this study were to differentiate between fresh frozen and heat treated orange juice employing descriptive analysis, and to determine by Osme, a gas chromatography-olfactometry (GCO) method, odor active volatiles that were either lacking or created in the heat treated juice. The second objective was to determine how changes in the odor-active volatile profile of heat treated orange juice, relates to changes in the aroma and flavor intensities of the samples as assessed by descriptive analysis. Through descriptive analysis, the panel was successful in significantly (p<0.05) separating the fresh, pasteurized, and concentrate samples. Orange, orange peel, sweet, and grassy descriptors were found to be important for fresh aroma and flavor, while cooked, yam, metallic, tamarind, green bean and artificial orange descriptors were higher in heat treated samples. Using Osme, it was possible to separate fresh frozen from heat treated orange juice, on the basis of their aroma profiles. Fresh frozen samples show a higher concentration of peaks tentatively identified as gamma-butyrolactone, citral, nonanal, carvone, perillaldehyde, carvyl propinate, valencene, and other unidentified peaks possessing descriptors such as floral, lime, citrus, pine, bamboo leaf, metallic, and vinyl. Pasteurized samples show a larger concentration of peaks tentatively identified as hexanol, octanol, nerol / carveol, myrcene, 2-octanone, p-cymene, terpenen-4-ol, betacitronellol, and other unidentified peaks with descriptors such as cilantro, vinyl, melon, mushroom, and metallic. Descriptors such as orange, orange peel, sweet, grapefruit, and grassy are more pronounced in the fresh samples and are similar to the odor descriptors of Osme peaks higher in the fresh samples. Descriptors such as cooked, artificial orange, yam, metallic, tamarind, and green bean are higher in the pasteurized samples, and are similar to the odor descriptors of peaks higher in these samples. / Graduation date: 1999

Electronic noses are targeted at determining odour character in a fashion that emulates conscious odour perception in mammals. The intention of this study was to develop an organisational framework for electronic noses and deploy a sample cheese odour discriminator within this framework. Biological olfactory systems are reviewed with the purpose of extracting the organisational principles that result in successful olfaction. Principles of gas handling, chemoreception, and neural processing are considered in the formulation of an organisational framework. An electronic nose is then developed in accordance with the biologically inspired framework. Gas sensing is implemented by an array of six commercially available (tin oxide) semiconductor sensors. These popular gas sensors are known to lack stability thus necessitating hardware and signal processing measures to limit or compensate for instability. An odorant auto-sampler was developed to deliver measured amounts of odorant to the sensors in a synthetic air medium. Each measurement event encodes a simulated sniff, and is captured across six sensor channels over a period of 256 seconds at a sampling rate of 1Hz. The simulated sniff captures sensor base references and responses to odorant introduction and removal. A technique is presented for representation and processing of sensor-array data as a two-dimensional (2D) image where one dimension encodes time, and the other encodes multi-channel sensory outputs. The near optimal, computationally efficient 2D Discrete Cosine Transform (DCT) is used to represent the 2D signal in a decorrelated frequency domain. Several coefficient selection strategies are proposed and tested. A heuristic technique is developed for the selection of transform domain coefficients as inputs to a non-linear neural network based classifier. The benefits of using the selection heuristic as compared to standard variance-based selection are evident in the results. Benefits include: significant dimensionality reduction with concomitant reduction in classifier size and training time, improved generalisation by the neural network and improved classification performance. The electronic nose produced a 99.1% classification rate across a set of seven different cheeses. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.

Thesis (Ph.D.)--Tufts University, 1999. / Adviser: David R. Walt. Submitted to the Dept. of Chemistry. Access restricted to members of the Tufts University community. Also available via the World Wide Web;