The present methods for the measurement of respiratory rate and volume of laboratory animals have been reviewed. The review suggests that these methods leave much to be desired. For this reason an apparatus has been developed in the hope that it may overcome the difficulties associated with those described in the literature. The apparatus consists of a mechanism to interrupt a beam of light in time with the animal's breathing, and the signal so produced is amplified to close a double pole double throw relay. The state of the relay, open or closed, selects an arrester on either the air supply spirometer or the air receiver spirometer. When the animal breathes in the air supply spirometer is free to move and the air receiver is locked allowing air to be taken from the air supply spirometer only. On expiration the reverse situation is in effect. A stylus attached to each spirometer records the downward or upward travel and hence the volume on a kymograph drum. An electro-magnetic stylus records each inspiration on the kymograph and a five second timer writes a time base. A limited amount of data on female and male guinea pigs is presented to indicate the validity of the measurements made with the apparatus. Equations based on these data relating respiratory rate and volume of the guinea pigs to body weight have been derived. These equations are compared with those of other workers and suggest that the apparatus devised may be superior to those described in the literature. / Land and Food Systems, Faculty of / Graduate

In situ light and dark planktonic and benthal respirometers were used to measure the oxygen requirements of Yaquina estuary water and benthal deposits. Respirometer devices were constructed so that actual conditions of mixing could be simulated and benthal deposit disturbance would be minimized. A mathematical model of a benthal respirometer was developed and was used to make corrections for respirometer leakage and to conduct oxygen transfer parameter sensitivity studies. The effect of mixing on benthal oxygen uptake was studied by varying the simulated mixing velocities. Studies were made to determine the effects of scour of bottom material on the salinity of the respirometer water and on the benthal oxygen uptake rates. Plots of various parameters such as benthal oxygen uptake versus dissolved oxygen concentration and respirometer leakage versus time were made to attempt to evaluate relationships that may exist. / Graduation date: 1970

Graduation date: 1993 / Figures in original are black and white photocopies. Best scan available.

The aim of this work was to verify the suitability of the device Ramko 2 for measuring the biological stability during the composting in terms of the Department of Agricultural Engineering. For this purpose were based four piles four piles with a similar composition and on which were measured temperature and DRI during all stages of composting. From the recorded data was created graphs both processes individual piles and compared with each other. From results assess the suitability for the authentication of biological stability.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-02-26T12:41:19Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Elivânia Vasconcelos Moraes dos Santos.pdf: 12370912 bytes, checksum: 6d2546d30ef4aaab7cbd742d981ddf1f (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-03-09T14:13:43Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Elivânia Vasconcelos Moraes dos Santos.pdf: 12370912 bytes, checksum: 6d2546d30ef4aaab7cbd742d981ddf1f (MD5) / Made available in DSpace on 2016-03-09T14:13:43Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Elivânia Vasconcelos Moraes dos Santos.pdf: 12370912 bytes, checksum: 6d2546d30ef4aaab7cbd742d981ddf1f (MD5) Previous issue date: 2014-12-15 / In recent years there has been an intensified studies on the biological removal of phosphorus from wastewater and as a result, a breakthrough in the understanding of the microbial groups involved in this process. This was possible due to the availability of different laboratory techniques for the identification and quantification of these organisms that often is associated with molecular biology. As part of sanitary engineering, new approaches can be inserted to enable the determination of operating parameters that support rational projects, such respirometry combined with mathematical modeling of microbial metabolisms. Furthermore, the possibility of identifying the predominance of phosphorus accumulating organisms (PAO) by means of techniques available and low cost is attractive in countries such as Brazil. For this reason, nine activated sludge systems were operated with different strategies to stimulate not only the predominance of PAO, in four of these systems as well as in other settings, the prevalence of other bacterial groups as glycogen storage batteries (GAO), heterotrophic ordinary (OHO) and mixed populations. Five tools based on physico-chemical and respirometric tests were used to assess the prevalence of different populations from stoichiometric ratios and kinetic data. The PAO predominance strategy that got the most attention in average temperature of 25°C, which consisted of a system that promoted denitrification via nitrite using exclusively propionate as organic carbon source. From the data obtained was built an array of predominance of PAO, also using mixed sludge, OHO and GAO comparatively. The results obtained in this study can be applied in rational models and optimized projects and support other biotechnological applications. / Nos últimos anos, tem havido uma intensificação de estudos sobre a remoção biológica de fósforo de águas residuárias e, como consequência, um avanço no conhecimento dos grupos microbianos envolvidos neste processo. Isso foi possível devido à disponibilidade de diferentes técnicas laboratoriais para a identificação e quantificação desses organismos que frequentemente encontra-se associada à biologia molecular. No âmbito da engenharia sanitária, novas abordagens podem ser inseridas para viabilizar a determinação de parâmetros operacionais que subsidiem projetos racionais, a exemplo da respirometria aliada à modelagem matemática de metabolismos microbianos. Além disso, a possibilidade de identificar a predominância de organismos acumuladores de fósforo (PAO) por meio de técnicas acessíveis e de baixo custo é atrativa para países como o Brasil. Por esse motivo, nove sistemas de lodo ativado foram operados com diferentes estratégias para estimular não só o predomínio de PAO, em quatro destes sistemas, bem como, nas demais configurações, a predominância de outros grupos bacterianos como acumuladores de glicogênio (GAO), heterotróficos ordinários (OHO) e populações mistas. Foram utilizadas cinco ferramentas com base em análises físico-químicas e testes respirométricos, para avaliar a predominância de populações diferentes a partir de relações estequiométricas e dados cinéticos. A estratégia de predominância de PAO que obteve maior destaque, em temperatura média de 25°C, foi a que consistia em um sistema que promovia desnitrificação via nitrito utilizando exclusivamente propionato como fonte de carbono orgânico. A partir dos dados obtidos foi construída uma matriz de predominância de PAO, utilizando também lodos mistos, OHO e GAO de forma comparativa. Os resultados obtidos neste trabalho poderão ser aplicados em modelos racionais e projetos otimizados e fundamentar outras aplicações biotecnológicas.

This project examines whether there is a direct link between respiration and the rate of senescence of fresh produce. Treatments that increase the storage life of fresh products, such as cooling, modified atmospheres and semi-permeable coatings, often decrease respiration rates. This suggests that it may be possible to assess the effectiveness of a specific storage treatment in terms of its effect on reducing respiration. If this is so, total respiration during storage should sum to a constant regardless of changes in the storage conditions. Such an equivalence between 'respiration life' and storage life has been demonstrated in only a few cases. Respiration data from a wide range of published work was analysed from the viewpoint of testing this hypothesis. In general, the results were positive, with some reservations that were further investigated by experiment. In conclusion, respiration rate may be a guide to storage life for products that have clearly defined stages of senescence, and for which rots are not the primary cause of the end of acceptability. The development of the respirometer should make it possible to examine this relationship for many other commodities. However, while respiration may be a function of the rate of senescence under some circumstances, it is also affected by other factors. These include photosynthesis, attachment to the plant, and permeance to gases. Directions for future work therefore include the contribution of photosynthesis to fruit development, the effects of ethylene on respiration rates of non-climacteric fruit while attached to the plant, and interactions between ethylene synthesis and disease resistance / Doctor of Philosophy (PhD)

Les bioprocédés environnementaux prennent une place de plus en plus importante dans le paysage industriel mondial. La complexité et la diversité des processus impliqués dans les réactions biologiques de dégradation des polluants limitent considérablement la compréhension et l’utilisation de ces procédés. De plus, les mesures disponibles pour le suivi de cette activité sont souvent hors-ligne et/ou indirectes. Dans ce cadre, les outils de modélisation phénoménologique permettent, via le choix d’hypothèses judicieuses, de lier les observations du système aux processus biologiques sous-jacents. Ces méthodes nécessitent néanmoins l’application d’une étude rigoureuse d’identifiabilité afin de pouvoir exploiter correctement les résultats obtenus. Les modèles ainsi développés permettent de capitaliser des connaissances sur la description des processus biologiques grâce aux mesures effectuées sur le système. Cette approche a été développé au travers de deux cas d’étude, correspondant à deux domaines d’application industrielle. La bioremédiation des sols contaminés aux hydrocarbures constitue la méthode la plus écologique de traitement des sols. Néanmoins, le processus de biodégradation peut être long, voire inexistant en fonction des conditions environnementales. Afin de mesurer l’efficacité de la dégradation, la mesure de la respiration en phase gaz apparaît comme étant l’observation la plus facile à mettre en œuvre. Le problème est que la simple mesure de la consommation d’oxygène est généralement insuffisante. Pour répondre à cette limite, un modèle capable d’expliquer les évolutions du quotient respiratoire apparent grâce aux différentes étapes de la biodégradation a été développé. Cette mesure pourrait alors donner une indication sur l’efficacité de la biodégradation. La seconde partie de ce travail, plus conséquente, s’intéresse à l’épuration des eaux usées par boues activées, elle reprend et amplifie l’approche méthodologique développée pour la biomédiation des sols. L’efficacité de ce traitement des eaux est grandement liée à la production de boues en excès, exprimée par le rendement hétérotrophe. Ce paramètre difficile à maitriser constitue une information primordiale pour la modélisation et la conduite des stations d’épurations. Il apparaît néanmoins que sa définition usuelle ne suffit pas à expliquer ses variations observées. Dans ce cadre, différents modèles phénoménologiques issus des travaux du groupe de travail ASM (Activated Sludge Modeling) ont été étudiés afin de décrire les variations de ce rendement apparent en introduisant les hypothèses réactionnelles liées au stockage du substrat. Une étude expérimentale en laboratoire a permis de confronter ces hypothèses à des mesures de dégradation de substrats purs par des boues activées en respiromètre. L’équilibre entre le stockage du substrat et la croissance bactérienne a ainsi été proposé comme source d’influence majeure sur la valeur du rendement. Ce travail a abouti à une clarification nécessaire de la définition du rendement hétérotrophe. / Environmental bioprocesses are gaining importance in the industrial landscape. Nevertheless, the complexity of mechanisms involved in biological reactions stays an issue for their implementation. Moreover, available measurements of biological activity are often off-tine and/or indirect. ln this context, phenomenological modeling tools are a solution to link observations of the system to underlying biological reactions, considering the right hypotheses. These methods require a rigorous sensitivity analysis in order to properly process the results. Thus, the models permit to obtain precise knowledge about biological systems thanks to indirect measurement. This approach was developed throughout two cases of study corresponding to two industrial fields of application. Bioremediation is the most ecological method for hydrocarbons contaminated soils remediation. Nevertheless, biodegradation can be long or absent depending on environmental conditions. In order to measure its efficiency, respiration measurement in the gas phase seems to be the easiest observation to implement. Oxygen measurement can be insufficient on its own, that is why a model able to describe the evolution of the apparent respiratory quotient has been developed considering the different steps of biodegradation. This observation alone could give insights on the efficiency of biodegradation. The second part of this work deals with activated sludge wastewater treatment using the theoretical approach developed for soil bioremediation. The eftïciency ofthe process depends on the excess production of sludge, which is linked to the heterotrophic yield of the reaction. This parameter is a key component for modeling and optimization of wastewater treatment plant. Most of the time, its common definition is not sufficient to explain its observed variations. In this context, several phenomenological models derived from the activated sludge models were studied to explain these variations, taking into account the substrate storage process. An experimental study was conducted in order to confront the reactional hypothesis of the models to actual measurements of single substrate degradations in respirometer. The balance between substrate storage and direct growth was proposed as a main component of the yield value. This study resulted in a necessary clarification of the heterotrophic yield definition.