Neural network models were developed to model the short-term concentration distribution of aerosols released from point sources. Those models were based on data from a wide range field experiments (November 2002, March, May and August 2003). The study focused on relative dispersion from the puff centroid. The influence of puff/cloud meandering and large-scale gusts were not considered, the modelling was limited to studying the dispersion caused by small-scale turbulence. The data collected were based on short range/time dispersion, usually shorter than 150 s. The ANN (Artificial Neural Network) models considered explicitly a number of meteorological and turbulence parameters, as opposed to the Gaussian models that used a single fitting parameter, the dispersion coefficient. The developed ANN models were compared with predictions generated from COMBIC (Combined Obscuration Model for Battlefield Induced Contaminants), a sophisticated model based on Gaussian distributions, and a traditional Gaussian puff model using Slade’s dispersion coefficients. Neural network predictions have been found to have better agreement with concentration measurements than either of the other two Gaussian puff models. All models underestimate the maximum concentration, but ANN predictions are much closer to observations. Simulations of concentration distributions under different stability conditions were also checked using the developed ANN model, and it showed that, for a short time, Gaussian distributions are a good fit for puff dispersion in the downwind, crosswind and vertical directions. For Gaussian puff models, the key issue is to determine appropriate dispersion coefficients (standard deviations). ANN models for puff dispersion coefficients were trained and their average predictions were compared with the results of measurements. Very good agreement was observed, with a high correlation coefficient (>0.99). The ANN models for dispersion coefficients were used to analyze which input variables were more significant for puff expansions. Dispersion time, particle position relative to the centroid, turbulent kinetic energy and insolation showed the most significant influence on puff dispersion. The Gaussian puff model with dispersion coefficients from the ANN models was compared with COMBIC and a Gaussian puff model using Slade’s dispersion coefficients. Generally speaking, predictions generated by the Gaussian puff model with dispersion coefficients generated by ANN models showed better agreement with concentration measurements than the other two Gaussian puff models, by giving a much higher fraction within a factor of two, and lower normalised mean square errors. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2007-10-17 12:13:42.923 / NSERC, DGNS

Understanding the factors that influence regular tobacco use often involves detailed assessment of individuals' smoking behavior (i.e., puff topography), including measuring puff number, volume, duration, and inter-puff interval (IPI) via mouthpiece-based, computerized devices. For example, puff topography measurement has been used to study smoking cessation medications, as well as to demonstrate brand-induced changes in smoking behavior. However, some research suggests that the use of a mouthpiece to evaluate puff topography may alter natural smoking behavior. Thus, this study was designed to compare topography measurement using mouthpiece-based methods (i.e., desktop and portable computerized devices) to methods that do not use a mouthpiece (i.e., direct observation via video recordings).Thirty smokers of "full-flavor" or "light" cigarettes (≥15 cigarettes/day) participated in six Latin-square ordered, 2.5-hour experimental sessions. Sessions were separated by at least 48 hours, and were preceded by at least 8 hours of objectively-verified tobacco abstinence (i.e., CO level ≤10 ppm). Conditions differed by type of cigarettes smoked (own brand, Merit® Ultra-light) and by type of topography measurement method used (desktop, portable, video observation). All three measurement methods were sensitive to manipulations of cigarette brand (i.e., increased puff duration and volume for own brand relative to ultra-light; P 0.68). All methods were also reliable, as demonstrated by high correlations across cigarette bouts within each condition (most r's > 0.78). In contrast, participants perceived the use of either mouthpiece-based device to alter aspects of their smoking behavior (e.g., increased difficulty, reduced enjoyment, altered cigarette taste; P < .05) relative to direct observation alone. Although direct observational methods may be optimal for measuring certain smoking characteristics, the many logistical challenges posed by this method likely limit its usefulness in a laboratory setting. Taken together, these results suggest that mouthpiece-based devices offer a convenient and useful tool for researchers examining smoking topography.

<p>U radu je ispitana mogućnost primene margarina za laminiranje smanjenog sadržaja trans masnih kiselina u izradi lisnatog peciva. U prvoj fazi eksperimentalnog rada ispitivanjem uticaja vrste (MZ1 i MZ2) i količine margarina za zames (1, 3 i 5% na masu bra&scaron;na) i količine emulgatora (0,1, 0,3, i 0,5% na masu bra&scaron;na), kao i njihove interakcije na fizičke osobine testa i kvalitet peciva, definisan je sirovinski sastav osnovnog testa, koji obezbeđuje optimalnu obradivost tokom laminiranja. Rezultati merenja empirijskih i fundamentalnih reolo&scaron;kih pokazatelja kvaliteta osnovnog testa i kvaliteta peciva jasno su pokazali da je optimalna količina dodataka 1% margarina MZ2 i 0,3% emulgatora.<br />Ispitivanjem uticaja sastava masne faze margarina za laminiranje na kvalitet peciva utvrđeno je da je količinu margarina, kao i vreme odmaranja između faza laminiranja neophodno prilagoditi fizičkohemijskim osobinama margarina. Zadovoljavajući kvalitet lisnatog peciva sa margarinom MLT1 najboljih fizičkih osobina, ali i najpoželjnijeg masnokiselinskog sastava, moguće je postići dodatkom samo 35% margarina, &scaron;to je najče&scaron;e donja granica u izradi lisnatog peciva. Za dobijanje prihvatljivih fizičkih i karakterističnih senzornih osobina peciva neophodan je dodatak 45% margarina MLT3, odnosno 55% margarina MLT2 i MLT4.<br />Primena margarina MLT1 i MLT4 koji imaju veći sadržaj čvrstih triglicerida zahteva vreme odmaranja od 30 minuta. Najbolji kvalitet peciva sa margarinom MLT2 ili MLT3 koje karakteri&scaron;e niži sadržaj SFC i manja tvrdoća dobija se kada je vreme relaksacije<br />između faza laminiranja 45 minuta.<br />Optimizacijom tehnolo&scaron;kog procesa proizvodnje peciva od laminiranog testa utvrđeno je da margarini niskog sadržaja trans masnih kiselina, kod kojih su očuvane optimalne fizičke osobine, mogu uspe&scaron;no da zamene margarine dobijene postupkom parcijalne hidrogenacije biljnog ulja. Primenom margarina modifikovanog sastava masne faze moguće je smanjiti energetsku vrednost peciva za 12%, odnosno smanjenjem udela masti za 30% i trans masnih kiselina za 100% pobolj&scaron;ati nutritivnu vrednost peciva.</p> / <p>The possibility of application of low-trans margarine in the puff pastry production was investigated in this work. The base dough formula, which ensures the optimal dough handling during the laminating, has been defined in the first phase of the experimental work. It has been achieved through the analysis of the influence of two dough margarines composition (MZ1 and MZ2) and quantity (1, 3 and 5 % based on flour) in combination with emulsifier quantity (0.1, 0.3 and 0.5% based on flour) on physical properties of dough and puff pastry quality. The results of the measurements of empirical and fundamental rheological parameters of the base dough quality as well as the quality of the puff pastry, have clearly indicated that the optimal quantity of margarine MZ2 and emulsifier are 1% and 0.3%, respectively.<br />By analyzing the impact of the fat phase composition of puff pastry margarine on pastry quality, it has been revealed that the quantity of the margarine and the relaxation time between laminating, need to be adjusted to the physicochemical characteristics of the margarine.<br />It is possible to achieve the satisfactory quality of the puff pastry with margarine MLT1 of the best physical, and of the most optimal fatty acid composition, by adding only 35% of margarine which is at most times, the lowest possible quantity in producing the puff pastry. For the achievement of the acceptable physical and typical sensory characteristics of the pastry it is needed to add 45 % of the margarine MLT3, or 55% of margarine MLT2 and MLT4.<br />The use of the margarines MLT1 and MLT4 which have high values of solid fat content, requires relaxation<br />time of 30 minutes. The best quality of the pastry with margarine MLT2 or MLT3 which is typical of lower solid fat content and lower firmness is achieved when the time of the relaxation between the laminating is 45 minutes.<br />By the optimization of the production of the puff pastry, it has been identified that the margarines of the low content of trans fatty acids can successfully replace the margarines produced by the partial hydrogenation of the vegetable oil. It is possible to reduce the energy value of the pastry by 12%, by using the margarine of the modified content of the fat phase. Namely by reducing the content of the fat by 30% and trans fatty acids by 100%, it is possible to improve the nutritive value of the pastry.</p>

A numerical reservoir model was created to optimize CO₂ Huff-and-Puff operations in the Bakken Shale. Huff-and-Puff is an enhanced oil recovery treatment in which a well alternates between injection, soaking, and production. Injecting CO₂ into the formation and allowing it to “soak” re-pressurizes the reservoir and improves oil mobility, boosting production from the well. A compositional reservoir simulator was used to study the various design components of the Huff-and-Puff process in order to identify the parameters with the largest impact on recovery and understand the reservoir’s response to cyclical CO₂ injection. It was found that starting Huff-and-Puff too early in the life of the well diminishes its effectiveness, and that shorter soaking periods are preferable over longer waiting times. Huff-and-Puff works best in reservoirs with highly-conductive natural fracture networks, which allow CO₂ to migrate deep into the formation and mix with the reservoir fluids. The discretization of the computational domain has a large impact on the simulation results, with coarser gridding corresponding to larger projected recoveries. Doubling the number of hydraulic fractures per stage results in considerably greater CO₂ injection requirements without proportionally larger incremental recovery factors. Incremental recovery from CO₂ Huff-and-Puff appears to be insufficient to make the process commercially feasible under current economic conditions. However, re-injecting mixtures of CO₂ and produced hydrocarbon gases was proven to be technically and economically viable, which could significantly improve profit margins of Huff-and-Puff operations. A substantial portion of this project involved studying alternative numerical methods for modeling hydraulically-fractured reservoir models. A domain decomposition technique known as mortar coupling was used to model the reservoir system as two individually-solved subdomains: fracture and matrix. A mortar-based numerical reservoir simulator was developed and its results compared to a tradition full-domain finite difference model for the Cinco-Ley et al. (1978) finite-conductivity vertical fracture problem. Despite some numerical issues, mortar coupling closely matched Cinco-Ley et al.'s (1978) solution and has potential applications in complex problems where decoupling the fracture-matrix system might be advantageous. / text

With substantial health and economic impacts attached to many highway-related projects, it has become imperative that the models used to assess air quality be as accurate as possible. The United States (US) Environmental Protection Agency (EPA) currently promulgates the use of CAL3QHC to model concentrations of carbon monoxide (CO) near roadway intersections. This model uses steady-state and macroscopic methods to model the physical phenomena (e.g., emission rates, atmospheric dispersion, etc.) occurring at intersections. These methods are not straightforward and unintuitive for the users. Therefore, this project investigated the possibility of developing a model that is theoretically more realistic and flexible than CAL3QHC. The new model entitled, Traffic Air Quality Simulation Model (TRAQSIM), uses a microscopic approach by modeling vehicle movements and dispersion in a simulation environment. Instead of steady-state plume equations used in the CAL3QHC model, TRAQSIM uses a discrete puff methodology that can be used to model time-based dispersion of pollutants. Most of the components incorporated into TRAQSIM have been drawn from existing methodologies and therefore, are not new. However, the combination of these different methods into a single integrated model is new and presents a novel approach to such a model. Initial verification and sensitivity/trend studies of the model indicate that TRAQSIM uses reasonable/realistic traffic parameters and behaves intuitively correct. A validation study showed that TRAQSIM produces good results when compared to actual measured data with an overall R2 value of 0.605 for 11 scenarios comprising 264 data points. Although most statistical parameters showed CAL3QHC agrees better overall with measured data (R2 value of 0.721), the comparisons were mixed on a scenario-by-scenario basis; that is, CAL3QHC showed better results for 6 scenarios and TRAQSIM showed better results for 5 scenarios. Additional tests with larger datasets, which were beyond the scope of this work, could be conducted to obtain more definitive conclusions and allow further development of TRAQSIM. While CAL3QHC is a mature model that has been developed over many years, TRAQSIM is new and has much more potential for improvement. The physical parameters used in TRAQSIM allow it to be more directly (more logically) improved than the approximations used in CAL3QHC. In addition, although the fundamental-level modeling in TRAQSIM make it a more complex model internally, it is much more intuitive for the user to understand and use.

No description available.

Durante o desenvolvimento deste projeto adotou-se como estratégia o sequenciamento de ESTs, com a finalidade de encontrar mensagens relacionadas com desenvolvimento, metabolismo e principalmente amplificação/politenização em glândulas salivares de Rhynchosciara americana, um díptero (Sciarídeo) que apresenta cromossomos politênicos e amplificação gênica rigidamente regulada ao longo do desenvolvimento larval, tanto neste tecido quanto em outros. Um total de 8193 ESTs foi gerado, estas foram anotadas e categorizadas segundo os termos do Gene Ontology Consortium, proporcionando uma visão geral do status metabólico, como em um Northern eletrônico, de um ponto importante no desenvolvimento desta espécie, quando surgem amplificações gênicas específicas e a glândula salivar necessita secretar as proteínas do casulo. Outros frutos deste seqüenciamento foram a determinação de 91 polimorfismos e a criação de uma tabela de códon usage. Diversos ESTs foram identificados com potencial envolvimento com os endociclos observados neste tecido, destes, RaDup e RaMCM5 foram selecionados para estudo. Suas regiões genômicas foram isoladas e suas localizações cromossômicas foram identificadas, em relação a RaDup, toda a porção codificante de seu mensageiro e 12kb de DNA genômico contendo seu gene foram seqüenciados, revelando sua estrutura gênica. Anticorpos foram produzidos para detectar esta proteína, gerando evidências de sua participação tanto na replicação mitótica como nos endociclos presentes nas glândulas salivares. A localização cromossômica de RaDup é um dado muito interessante, pois pela primeira vez um pufe amplificado é relacionado com um gene regulatório. / In this work EST sequencing was used as strategy to find messages related to development, metabolism and polyteny/amplification in salivary glands of Rhynchosciara americana, a dipteran (Sciaridae) that shows in this tissue giant polytene chromosomes and gene amplification tightly regulated throughout development of the larvae. A total of 8193 EST sequences were generated, annotated and categorized using Gene Ontology Consortium terms, providing a general view of the metabolic status, like an electronic Northern, of an important point in development of the larvae, that shows where specific genes are amplified and the salivary gland needs to secrete the proteins to form the cocoon. Other data include determination of 91 SNPs and a statistic of codon usage. Several ESTs were identified with potential connection to endocicles, from these RaDup and RaMCM5 were selected for further studies. Both chromosomal loci were identified and genomic regions isolated, for RaDup the coding region of its mRNA and 12kb of genomic region were completely sequenced, revealing its gene structure, and antibodies were raised against this protein, making evident data about its involvement in replication in mitotic cells and in endocicles in salivary glands. About the chromosomal locus of RaDup, it becomes very interesting, because for the first time one amplified puff can be related to a regulatory gene.

Ca2+ is a universal intracellular messenger that regulates many cellular responses. Most cells express inositol 1,4,5-trisphosphate receptors (IP3R) that mediate Ca2+ release from the endoplasmic reticulum (ER) when they bind IP3 produced after activation of cell-surface receptors. Vertebrate genomes encode three closely related subtypes of IP3R (IP3R1-3). High-resolution optical analyses have revealed a hierarchy of IP3-evoked Ca2+ signals that are thought to arise from the co-regulation of IP3Rs by IP3 and Ca2+. The smallest events ('blips') report the opening of single IP3Rs, Ca2+ 'puffs' report the almost simultaneous opening of a few clustered IP3Rs, and as stimulus intensities increase further Ca2+ signals propagate regeneratively as Ca2+ waves. The aim of this study was to establish whether all three IP3R subtypes can generate Ca2+ puffs. I first used a haploid cell line (HAP1 cells) to generate, using CRISPR/Cas9, a line lacking all endogenous IP3Rs. However, for analyses of Ca2+ puffs, I used HEK cells that had been engineered, using CRISPR/Cas9 to disrupt endogenous genes, to express single IP3R subtypes. Local Ca2+ signals evoked by flash-photolysis of caged- IP3 were recorded using Cal520 and total internal reflection fluorescence (TIRF) microscopy in human embryonic kidney (HEK) cells. The Flika algorithm was used, and validated, for automated detection of Ca2+ puffs and to measure their properties. IP3 evoked Ca2+ puffs in wild-type HEK cells and in cells expressing single IP3R subtypes. In wild-type cells, the Ca2+ signals invariably propagated regeneratively to give global increases in cytosolic [Ca2+]. This occurred less frequently in cells expressing single IP3R subtypes, commensurate with their lower overall levels of IP3R expression. The properties of the Ca2+ puffs, including their rise and decay times, durations, the size of the unitary fluorescence steps as channels closed channel during the falling phase, and the estimated number of active IP3Rs in each Ca2+ puff, were broadly similar in each of the four cell lines. The latter observation suggests that despite lower overall levels of IP3R expression (~30%) in cells with single subtypes relative to WT cells, there is a mechanism that ensures formation of similarly sized IP3R clusters. The only significant differences between cell lines were the slower kinetics of the Ca2+ puffs evoked by IP3R2, which may suggest dissociation of IP3 from its receptor contributes to the termination of Ca2+ puffs. My results demonstrate, for the first time, that all three IP3R subtypes can generate Ca2+ puffs. I conclude that Ca2+ puffs are fundamental building blocks of all IP3-evoked Ca2+ signals.

Durante o desenvolvimento deste projeto adotou-se como estratégia o sequenciamento de ESTs, com a finalidade de encontrar mensagens relacionadas com desenvolvimento, metabolismo e principalmente amplificação/politenização em glândulas salivares de Rhynchosciara americana, um díptero (Sciarídeo) que apresenta cromossomos politênicos e amplificação gênica rigidamente regulada ao longo do desenvolvimento larval, tanto neste tecido quanto em outros. Um total de 8193 ESTs foi gerado, estas foram anotadas e categorizadas segundo os termos do Gene Ontology Consortium, proporcionando uma visão geral do status metabólico, como em um Northern eletrônico, de um ponto importante no desenvolvimento desta espécie, quando surgem amplificações gênicas específicas e a glândula salivar necessita secretar as proteínas do casulo. Outros frutos deste seqüenciamento foram a determinação de 91 polimorfismos e a criação de uma tabela de códon usage. Diversos ESTs foram identificados com potencial envolvimento com os endociclos observados neste tecido, destes, RaDup e RaMCM5 foram selecionados para estudo. Suas regiões genômicas foram isoladas e suas localizações cromossômicas foram identificadas, em relação a RaDup, toda a porção codificante de seu mensageiro e 12kb de DNA genômico contendo seu gene foram seqüenciados, revelando sua estrutura gênica. Anticorpos foram produzidos para detectar esta proteína, gerando evidências de sua participação tanto na replicação mitótica como nos endociclos presentes nas glândulas salivares. A localização cromossômica de RaDup é um dado muito interessante, pois pela primeira vez um pufe amplificado é relacionado com um gene regulatório. / In this work EST sequencing was used as strategy to find messages related to development, metabolism and polyteny/amplification in salivary glands of Rhynchosciara americana, a dipteran (Sciaridae) that shows in this tissue giant polytene chromosomes and gene amplification tightly regulated throughout development of the larvae. A total of 8193 EST sequences were generated, annotated and categorized using Gene Ontology Consortium terms, providing a general view of the metabolic status, like an electronic Northern, of an important point in development of the larvae, that shows where specific genes are amplified and the salivary gland needs to secrete the proteins to form the cocoon. Other data include determination of 91 SNPs and a statistic of codon usage. Several ESTs were identified with potential connection to endocicles, from these RaDup and RaMCM5 were selected for further studies. Both chromosomal loci were identified and genomic regions isolated, for RaDup the coding region of its mRNA and 12kb of genomic region were completely sequenced, revealing its gene structure, and antibodies were raised against this protein, making evident data about its involvement in replication in mitotic cells and in endocicles in salivary glands. About the chromosomal locus of RaDup, it becomes very interesting, because for the first time one amplified puff can be related to a regulatory gene.

The dissertation thesis deals with short-term gas releases (puffs) in an urban canopy studied utilizing wind-tunnel modelling. The urban canopy was composed of buildings with pitched roofs organised into closed courtyards. Into it, a ground-level point gas source was placed. The first part of the thesis is focused on specific definitions of puff characteristics. New definitions of puff arrival and departure times are presented. Various definitions of puff arrival time were applied on the same datasets and the results were compared. Moreover, it was studied how slight changes in determination of puff departure time can affect its values and other derived puff characteristics. The second part of the thesis is focused on modelling of probability density functions of puff characteristics with knowledge of sampling positions towards the gas source and mean values of concentrations valid for long-term gas sources. The found equations will be utilized in an operational model. The outputs in the form of the probability density functions of puff characteristics distinguish my model from the usually utilized operational models, in which only the ensemble-averaged puff outline and concentration field can be predicted.