The performance and stability of a thermophilic anaerobic digestion system are inherently dependent on the engineered environment within each reactor. While the selection of operational parameters such as mixing, solids retention time, and digestion temperature are often selected on the basis of certain desirable outcomes such as the deactivation of human pathogens, these parameters have been shown to have a broad impact on the overall sludge digestion process. Since the current time-temperature requirements for biosolids pathogen reduction are most easily met at elevated digestion temperatures within the thermophilic range, it is certainly worth examining the effect of specific digestion temperatures on ancillary factors such as operational stability and the aesthetic quality of biosolids. A series of experiments were carried out in which wastewater sludge was digested at a range of temperatures (35°C, 49°C, 51°C, 53°C, 55°C, 57.5°C). Each reactor was operated for a period at steady state in order to make observations of microbial activity, digestion performance, and biosolids aesthetics as affected solely by digestion temperature. Results of this study show that poor operational stability arises in reactors operated at 57.5°C. Elevated concentrations of hydrogen and short-chain fatty acids in the 57.5°C digesters are evidence that the observed temperature-induced digester failures are related to the temperature sensitivity of hydrogenotrophic (CO₂-reducing) methanogens. Reactors operated at other temperatures performed equally well with respect to solids removal and operational stability. In addition, peak volatile organic sulfur compound (VOSC) production from biosolids treated at 51°C and above was greatly reduced in comparison with mesophilic anaerobic digestion and a lower temperature (49°C) thermophilic system. Since the biosolids methanogenic community appeared to be equally capable of degrading VOSC over the range of thermophilic temperatures, the conclusion is that the activity of VOSC producing organisms in digested and dewatered biosolids is greatly reduced when operating temperature in excess of 51°C are used. This study shows that small changes in an operationally defined parameter such as digestion temperature can have a large impact on the performance and stability of a digestion process. Single minded selection of digestion temperature in order to achieve effective pathogen reduction can result in poor digester performance and the production of an aesthetically unacceptable product. Careful selection, however, of an appropriate digestion temperature can not only ensure successful pathogen reduction in compliance with current regulations, but can also improve the performance, stability, and aesthetic quality of digestion systems employing thermophilic anaerobic digestion. / Master of Science

Cyanobacteria are a naturally occurring component of reservoir aquatic ecosystems. Given that some species possess the ability to control their depth within the water column, they have a competitive advantage over other species of photosynthetic organisms. This leads to the potential for cyanobacteria blooms, and because of taste and odor problems, as well as possible toxin production associated with certain species of cyanobacteria, these organisms can cause major problems in drinking water production. The Western Virginia Water Authority installed a solar-powered circulator in Falling Creek Reservoir, located in Bedford County, Virginia, in an attempt to limit the growth of these organisms through limiting light exposure by circulating them deeper within the reservoir. Experiments were performed during the summer of 2008 to quantify the effect of the circulator on the reservoir. Temperature, dissolved oxygen, water velocity, and photosynthetic yield were monitored before and during operation of the unit. The overall effect of the mixer was limited to the first 10 m immediately adjacent to the unit during the afternoon. The effect was stronger during the morning when the difference in density between the intake water and the surface of the reservoir was smaller, allowing the water to travel up to 80 m away from the unit. Although the circulator was only intended to mix and possibly deepen the epilimnion, the entire reservoir became mixed about two weeks after the circulator was put into operation. The reservoir is quite shallow, leading to a weak stratification that is easily disrupted by the operation of the circulator. / Master of Science

Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 85-110.

The axilla is a major source of human body odour from which the characteristic musky, urinous or acidic odours emanate, and are predominantly due to bacterial metabolism of the protein-rich fluid secreted by the apocrine and sebaceous glands located in this area (Senol and Fireman, 1999). Clothing has been implicated in contributing to body odour intensity, possibly even increasing the intensity (Dravnieks, et al., 1968; Shelley, et al., 1953) by the transfer of secretions, skin debris and bacteria from the body to the fabric substrate. Despite much anecdotal evidence indicating that some fibres and fabrics are better at limiting odour intensity than others, there appears to be no published research confirming this. The purpose of this study therefore, was to determine whether fabrics varying in fibre content (cotton, wool, polyester) and fabric knit structure (interlock, single jersey, 1x1 rib) differed in the extent to which they retained and emanated axillary odour following wear, and whether the intensity of odour was linked to the number of bacteria transferred to the fabrics. A procedure for collecting odour on fabrics was developed as was a method for evaluating odour through use of a sensory panel. Total aerobic bacteria and aerobic coryneform bacteria extracted from the fabrics were counted to determine if an association between bacterial counts and fabrics existed. Sensory analysis recognises the unique capability of humans as odour-detecting instruments whereas, instrumental analysis has the potential to offer information on the concentration and identification of axillary compounds, which a human assessor cannot. To investigate a new method for detecting axillary odour on apparel fabrics, proton transfer reaction mass spectrometry (PTR-MS) was used to analyse volatiles emitted from fabrics differing in fibre type. After removal of garments from the human body, axillary odour can be detected on fabrics, with the intensity of odour being strongly influenced by the fibre type from which the fabrics had been made. Polyester fabrics emanated odour of high intensity, cotton that of mid-low odour intensity, and wool fabrics were low odour. Fabric structural properties such as thickness, mass per unit area and openness of knit structure also had an effect on odour intensity. However, as the principal factor influencing odour intensity was fibre, only fabrics characterised by a high intensity (i.e. polyester) were influenced by structural properties. Differences in odour intensity among fabrics were not necessarily related to bacterial numbers, and no �inherent antimicrobial� properties were evident for any of the fabrics. Bacterial populations persisted in all fabrics up to 28 days. A decline in numbers was apparent for high-odour polyester fabrics, while numbers in low-odour wool fabrics remained relatively stable. PTR-MS detected compounds likely to be short-chain carboxylic acids which increased in the headspace above the polyester fabrics after 7 days. However, this increase was not evident for either the wool or cotton fabrics. Therefore, bacterial numbers per se cannot be a predictor of the odour intensity emanating from fabrics at least on the basis of these fabrics and fibres. The intensity of axillary odour emanating from fabrics was found inversely related to fibre hygroscopicity. Keywords:fibre content, fabric structure, axillary odour, sensory analysis, bacteria, corynebacteria, instrumental analysis, PTR-MS

Bibliography: p. 331-340. / x, 340 p. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Using sensory ranking, studies aroma variability of a chardonnay and a cabernet sauvignon matured in new oak barrels. Oak wood-derived volatile compounds are analysed using gas chromatography, to suggest which natural and cultural variables are involved in each aroma variation. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1998

Thesis (M.S. in pharmacology and toxicology)--Washington State University, May 2010. / Title from PDF title page (viewed on July 23, 2010). "Graduate Program in Pharmacology and Toxicology." Includes bibliographical references (p. 25-30).

The description of odour, frequent in Zola's work, has been little studied, most researchers having focused only on the visual description of this novelist. This dissertation, taking as its corpus Les Rougon-Macquart, explores this issue. The working hypothesis is that Zola reveals his impressionist tendencies in this type of description. The first chapter presents a brief history of the status of olfaction and description of odour in its philosophical, social as well as in literary context. The following chapter, after having defined a few concepts (notions from Hamon and Adam), presents the status of the description of odour in Zola's work. Four recurrent devices emerge: redundancy, multi-sensorial description, clausulae and turning points. The third chapter begins the study of the internal working of the description by examining the lexicon of odour. The lexicon of odour as used by Zola resorts mostly to the emotional and poetical functions of language. The final chapter continues the examination of modes of structuration, using Adam's notion of plan of text. The text concludes by maintaining that Zola's uniqueness is based on his marriage of impressionism and realism-naturalism. (Abstract shortened by UMI.)

Behavioral responses to social odors in Syrian hamsters are regulated by brain structures including the medial amygdala (Me) and bed nucleus of the stria terminalis (BNST). The role of these areas in regulating social behaviors has been previously studied in detail. However, the chemical phenotypes of neurons in these areas have not been well defined. Based on previous literature, we hypothesize that there is an increase in Me GABAergic signaling in response to social odors in male hamsters. To test this, we quantified colocalization of Calbindin and Fos in the Me of male hamsters after odor exposure. There were no significant differences in the percentage of Fos+ cells that were CB+ between odor conditions, but the percentage of CB+ cells that were Fos+ was higher in subjects exposed to conspecific odors versus clean odors. This implies that CB+ neurons transmit social information in the Me of male hamsters.

Knowledge about the use and behavioural relevance of the different senses in the South American Coati is limited. The aim of the present study was therefore to investigate the use of the sense of smell in this species. Twenty-five captive coatis were observed at the zoo of La Paz for a total of 120 hours to collect data on olfactory-related behaviors. The coatis frequently performed behaviors in response to the detection of odors such as sniffing on the ground, on objects, on food, on conspecifics, or in the air. In contrast, they did not display many odor depositing behaviors such as urinating, defecating, or scent-marking. The most frequently performed olfactory-related behavior was “sniffing on ground” which accounted for an average of 40 % of all recorded behaviors. In general, both adult males and non-males (here defined as adult females, as well as sub-adults and juveniles of both sexes) performed olfactory-related behaviors at similar frequencies. However, a few frequency differences for certain behaviors were found in the morning and in the afternoon, and in food or no food conditions, respectively. When food was present, for example, the coatis spent less time on olfactory-related foraging behaviors like “sniffing on ground” and “nose-digging” compared to when food was not present. The finding that scent-marking was rare in this captive group, indicates little need for territorial marking or communication of reproductive state under these circumstances. Findings from this study support the idea that Nasua nasua use their sense of smell in a variety of different contexts, and further studies are needed to extend the results.

The axilla is a major source of human body odour from which the characteristic musky, urinous or acidic odours emanate, and are predominantly due to bacterial metabolism of the protein-rich fluid secreted by the apocrine and sebaceous glands located in this area (Senol and Fireman, 1999). Clothing has been implicated in contributing to body odour intensity, possibly even increasing the intensity (Dravnieks, et al., 1968; Shelley, et al., 1953) by the transfer of secretions, skin debris and bacteria from the body to the fabric substrate. Despite much anecdotal evidence indicating that some fibres and fabrics are better at limiting odour intensity than others, there appears to be no published research confirming this. The purpose of this study therefore, was to determine whether fabrics varying in fibre content (cotton, wool, polyester) and fabric knit structure (interlock, single jersey, 1x1 rib) differed in the extent to which they retained and emanated axillary odour following wear, and whether the intensity of odour was linked to the number of bacteria transferred to the fabrics. A procedure for collecting odour on fabrics was developed as was a method for evaluating odour through use of a sensory panel. Total aerobic bacteria and aerobic coryneform bacteria extracted from the fabrics were counted to determine if an association between bacterial counts and fabrics existed. Sensory analysis recognises the unique capability of humans as odour-detecting instruments whereas, instrumental analysis has the potential to offer information on the concentration and identification of axillary compounds, which a human assessor cannot. To investigate a new method for detecting axillary odour on apparel fabrics, proton transfer reaction mass spectrometry (PTR-MS) was used to analyse volatiles emitted from fabrics differing in fibre type. After removal of garments from the human body, axillary odour can be detected on fabrics, with the intensity of odour being strongly influenced by the fibre type from which the fabrics had been made. Polyester fabrics emanated odour of high intensity, cotton that of mid-low odour intensity, and wool fabrics were low odour. Fabric structural properties such as thickness, mass per unit area and openness of knit structure also had an effect on odour intensity. However, as the principal factor influencing odour intensity was fibre, only fabrics characterised by a high intensity (i.e. polyester) were influenced by structural properties. Differences in odour intensity among fabrics were not necessarily related to bacterial numbers, and no �inherent antimicrobial� properties were evident for any of the fabrics. Bacterial populations persisted in all fabrics up to 28 days. A decline in numbers was apparent for high-odour polyester fabrics, while numbers in low-odour wool fabrics remained relatively stable. PTR-MS detected compounds likely to be short-chain carboxylic acids which increased in the headspace above the polyester fabrics after 7 days. However, this increase was not evident for either the wool or cotton fabrics. Therefore, bacterial numbers per se cannot be a predictor of the odour intensity emanating from fabrics at least on the basis of these fabrics and fibres. The intensity of axillary odour emanating from fabrics was found inversely related to fibre hygroscopicity. Keywords:fibre content, fabric structure, axillary odour, sensory analysis, bacteria, corynebacteria, instrumental analysis, PTR-MS