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EFFECTS OF AGING ON NUTRIENTS DIGESTIBILITY IN NONHUMAN PRIMATESChoi, Heesun, 1954- January 1986 (has links)
No description available.
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The effects of radiolytically generated free radicals on aqueous amylase samplesTierney, David Patrick January 2000 (has links)
No description available.
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Soft sensor development and process control of anaerobic digestionArgyropoulos, Anastasios January 2013 (has links)
This thesis focuses on soft sensor development based on fuzzy logic used for real time online monitoring of anaerobic digestion to improve methane output and for robust fermentation. Important process parameter indicators such as pH, biogas production, daily difference in pH and daily difference in biogas production were used to infer alkalinity, a reliable indicator of process stability. Additionally, a fuzzy logic and a rule-based controller were developed and tested with single stage anaerobic digesters operating with cow slurry and cellulose. Alkalinity predictions from the fuzzy logic algorithm were used by both controllers to regulate the organic loading rate that aimed to optimise the biogas process. The predictive performance of a software sensor determining alkalinity that was designed using fuzzy logic and subtractive clustering and was validated against multiple linear regression models that were developed (Partner N° 2, Rothamsted Research 2010) for the same purpose. More accurate alkalinity predictions were achieved by utilizing a fuzzy software sensor designed with less amount of data compared to a multiple linear regression model whose design was based on a larger database. Those models were utilised to control the organic loading rate of a twostage, semi-continuously fed stirred reactor system. Three 5l reactors without support media and three 5l reactors with different support media (burst cell reticulated polyurethane foam coarse, burst cell reticulated polyurethane foam medium and sponge) were operated with cow slurry for a period of seven weeks and twenty weeks respectively. Reactors with support media were proven to be more stable than the reactors without support media but did not exhibit higher gas productivity. Biomass support media were found to influence digester recovery positively by reducing the recovery period. Optimum process parameter ranges were identified for reactors with and without support media. Increased biogas production was found to occur when the loading rates were 3-3.5g VS/l/d and 4-5g VS/l/d respectively. Optimum pH ranges were identified between 7.1-7.3 and 6.9-7.2 for reactors with and without support media respectively, whereas all reactors became unstable at ph<6.9. Alkalinity levels for system stability appeared to be above 3500 mg/l of HCO3 - for reactors without media and 3480 mg/l of HCO3 - for reactors with support media. Biogas production was maximized when alkalinity was 3 between 3500-4500 mg/l of HCO3 - for reactors without support media and 3480- 4300 mg/l of HCO3 - for reactors with support media. Two fuzzy logic models predicting alkalinity based on the operation of the three 5l reactors with support media were developed (FIS I, FIS II). The FIS II design was based on a larger database than FIS I. FIS II performance when applied to the reactor where sponge was used as the support media was characterized by quite good MAE and bias values of 466.53 mg/l of HCO3- and an acceptable value for R2= 0.498. The NMSE was close to 0 with a value of 0.03 and a slightly higher FB= 0.154 than desired. The fuzzy system robustness was tested by adding NaHCO3 to the reactor with the burst cell reticulated polyurethane foam medium and by diluting the reactor where sponge was used as the support media with water. FIS I and FIS II were able to follow the system output closely in the first case, but not in the second. FIS II functionality as an alkalinity predictor was tested through the application on a 28l cylindrical reactor with sponge as the biomass support media treating cow manure. If data that was recorded when severe temperature fluctuations occurred (that highly impact digester performance), are excluded, FIS II performance can be characterized as good by having R2= 0.54 and MAE=Bias= 587 mg/l of HCO3-. Predicted alkalinity values followed observed alkalinity values closely during the days that followed NaHCO3 addition and water dilution. In a second experiment a rulebased and a Mamdani fuzzy logic controller were developed to regulate the organic loading rate based on alkalinity predictions from FIS II. They were tested through the operation of five 6.5l reactors with biomass support media treating cellulose. The performance indices of MAE=763.57 mg/l of HCO3-, Bias= 398.39 mg/l of HCO3-, R2= 0.38 and IA= 0.73 indicate a pretty good correlation between predicted and observed values. However, although both controllers managed to keep alkalinity within the desired levels suggested for stability (>3480 mg/l of HCO3-), the reactors did not reach a stable state suggesting that different loading rates should be applied for biogas systems treating cellulose.
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Energy and material balances of wastewater treatment, including biogas production, at a recycled board millAssis Lana e Cruz, Igor January 2016 (has links)
Challenges surrounding energy have gained increased attention, which is not least reflected in the 2030 Agenda for Sustainable Development and the Sustainable Development Goals (SDGs). Energy issues have also become a pressing matter for most countries in the last decades. The reasons for this are not only related to the effects of the emission of greenhouse gases (GHG) from fossil fuels and their impact in climate change, but also span through other issues such as security of energy supply with geopolitical considerations and competitiveness of industry. To address these issues, a collection of public policies ranging from the international to local levels have been implemented. Sweden has historically had lower energy prices than its European counterparts, which has resulted in its industry having a relatively higher share of electricity in the total energy use by industry. The share of electricity accounts for 35% of total energy use in Swedish industry. This has led to efficiency measures being overlooked by industry, and the pulp and paper industry is by far the biggest energy user, with a share of 51% of the total energy use by industry. The variation of energy prices, and particularly electricity prices have obvious implications on the competitiveness of this sector. Production of biogas in pulp and paper mills has been gaining attention, and is now the target of an increasing number of scientific studies. The interest for this industry is not only related to security of energy supply and the environmental performance of the biogas itself, but there are also considerations regarding the biogas plant as an alternative to treat the large flows of wastewaters and other waste stream in this sector. There is an estimated biogas production potential of 1 TWh within this industry in Sweden, which accounts for 60% of the current biogas production in the country. Pulp and paper mills commonly rely on aerated biological treatment to deal with waste streams with high organic content This biological process has a high energy demand, and the integration of an anaerobic treatment, along with the use of the biogas for heat and electricity can yield a net positive energy recovery for the combined plant. This project analyses the current energy and material performance of an anaerobic biological treatment combined with an aerobic biological treatment in a recycled board mill. The anaerobic treatment is performed upstream of the aerobic one and removes most of the chemical oxygen demand of the wastewater. Energy and material balances for the plant are presented, and a comparison of the wastewater treatment plant running before and after the start-up of the biogas plant is made. The plant operation with the anaerobic digestion has shown an increased energy use of 9.4% coupled to an increased flow of wastewater of 7.7%. The average biogas production is 72 Nm³/h, which accounts for 440 kWh and is currently being flared. The introduction of AD has largely decrease the organic load in the aerobic treatment, by nearly 50%. This project ends with an optimisation model implemented with the optimisation tool reMIND to investigate potential optimisation strategies for the operation of the combined plant. The model has shown to be adequate to describe electricity use with mean error below 10%. For the biogas production, the mean error was of 16%.
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Removal of siloxanes from biogasHepburn, Caroline Amy January 2014 (has links)
Economic utilisation of biogas arising from sewage sludge is hampered by the need to remove siloxanes, which damage gas engines upon combustion. This thesis applies on-line Fourier transform infrared spectroscopy to measure siloxanes in biogas upstream and downstream of the activated carbon vessels designed to adsorb siloxanes. On-line analysis provides accurate measurement of siloxane concentrations with a detection limit below the siloxane limits set by engine manufacturers, high data intensity and timely identification of breakthrough. Cost savings of up to £0.007 kWh- 1 may be realised compared to existing grab sampling. Using on-line analysis, the performance of full-scale and bench-scale carbon vessels were measured. Full-scale carbon contactors are typically operated at Reynold’s numbers close to the boundary between the laminar and transitional regimes (Re = 40 - 55). This thesis demonstrates, at full- and bench-scale, that increasing the Reynold’s number to site the adsorption process in the transitional regime increases media capacity, by 36% in dry gas and by 400% at 80% humidity. It is postulated that the change in gas velocity profile which occurs as Reynold’s number increases reduces the resistance to siloxane transport caused by gas and water films around the carbon particles, and therefore increases the rate of the overall adsorption process. In the laminar regime (Re = 31) increasing humidity from zero to 80% led to the classical stepwise reduction in adsorption capacity observed by other researchers, caused by the increasing thickness of the water film, but in the transitional regime (Re = 73) increasing humidity had no effect as no significant water film develops. It is therefore recommended that siloxane adsorption vessels should be designed to operate at Reynold’s numbers above 55. By choosing a high aspect ratio (tall and thin) both Reynold’s number and contact time can be optimised.
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Limelight & IndigestionThorud, Joshua D 01 January 2015 (has links)
This thesis chronicles the progression toward and creation of my thesis show, Limelight & Indigestion, as well as the cultural, technological and artistic influences and discussions that underpin the works therein. The show is an exploration of celebrity, mass media, and the nature of the desire for fame. I hope to situate my work through an investigation of topics such as Hollywood and the use of green screens and associated technology, our physical and ideological connection to cinema, the absurd in cinema history, and the complex nature of media digestion.
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Trávení krve u flebotomů a jeho vliv na vývoj leishmanií / Bloodmeal digestion of phlebotomine sand flies and its effect on Leishmania developmentPružinová, Kateřina January 2012 (has links)
Leishmania development in their vectors is closely connected with bloodmeal digestion. This thesis focuses on factors affecting bloodmeal digestion, egg development and Leishmania infection within the sand fly gut. First, we compared the effect of mammalian (rabbit) and avian (chicken) blood on digestion and eggs development in Phlebotomus duboscqi. Sand flies fed on chickens had twice lower protein concentrations in the midgut and significantly lower trypsin activity compared to those fed on rabbits. The highest differences in the trypsin activity were observed during first 24 hours post bloodmeal. In addition, females fed on chickens had slower eggs development and their eggs were 10 % smaller compared to those fed on rabbits. In the second part of the thesis we tested the effect of mosquito hormone TMOF on the trypsin activity and eggs development of Lutzomyia longipalpis. Rabbit blood with TMOF (28 mg/ml) was presented to the females via a membrane feeding system. Sand flies fed on blood with TMOF had 15 - 35 % less trypsin activity than control females fed on only rabbit blood. In addition, females fed on blood with TMOF had developed 30 % less eggs and their eggs were 12 - 24 % smaller compared to control group. However the effect of TMOF we observed was lower than that described previously...
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Estratégias e fisiologia do consumo e digestão de esponjas (Porifera) por Echinaster brasiliensis (Echinodermata: Asteroidea) / Strategies and physiology of the consumption and digestion of sponges (Porifera) by Echinaster brasiliensis (Echinodermata: Asteroidea)Queiroz, Camila Helena de Souza 10 July 2012 (has links)
Esponjas são sésseis e possuem um esqueleto constituído por elementos inorgânicos microscópicos (espículas), fibras de colágeno e/ou combinações destes dois componentes. Embora sem proteções físicas evidentes tais como conchas ou espinhos, são pouco predadas, sendo este fato atribuído principalmente a presença de metabólitos secundários ativos. Recentemente, um papel dos componentes esqueléticos como deterrente foi experimentalmente confirmado, mas sua importância relativa ainda é bastante debatida. Algumas estrelas-do-mar são consideradas como espongívoras, e a literatura existente geralmente coloca que a digestão é realizada externamente, sem ingestão do esqueleto da presa. Desta forma, neste trabalho foram verificados o comportamento alimentar da estrela-do-mar Echinaster brasiliensis em relação às esponjas, o destino dos componentes esqueléticos e seus efeitos na fisiologia do organismo. Observações de campo e experimentos em laboratório foram efetuados para determinar a estratégia de consumo utilizada pela estrela. O processo digestivo do material esquelético (espículas e/ou fibras) foi acompanhado até a eliminação. Foi verificado que E. brasiliensis se alimenta de diferentes espécies de esponjas, mas não consome apenas estes organismos, sendo mais generalista do que o suposto. As preferências no consumo das esponjas são determinados por fatores diversos, como a quantidade de matéria orgânica ou formato do organismo predado. A ingestão ocorre com a eversão do estômago, mas ao contrário do descrito para outras espécies, E. brasiliensis ingere componentes esqueléticos, sendo espículas encontradas inseridas no epitélio digestivo. Entretanto, essa ingestão é baixa e aparentemente não causa injúrias severas ao organismo, sendo as espículas descartadas no material fecal / Sponges are sessile and have a skeleton made of microscopic inorganic elements (spicules), collagen fibers and/or combinations of these two components. Although without clear physical defenses such as shells or spines, they are not preyed upon, and this is attributed mainly to the presence of active secondary metabolites. Recently, a role of skeletal components as deterrents has been experimentally confirmed, but its relative importance is still debated. Some starfishes are regarded as spongivorous, and the existing literature generally considers that the digestion is performed externally, without intake of the sponge skeleton. In this study the feeding behavior of the starfish Echinaster brasiliensis in relation to sponges, the fate of skeletal components and their effects on the starfish physiology were studied. Field observations and laboratory experiments were conducted to determine the consumption strategies used by the starfish. The digestive process of the skeletal material (spicules and/or fibers) was followed until the elimination. It was found that E. brasiliensis feeds on different species of sponges, but does not consume only these organisms, being more generalist than assumed. Preferences in the consumption of sponges were determined by several factors, such as the amount of organic matter or shape of the preyed organism. The intake occurs by the eversion of the stomach, but unlike what is described for other species E. brasiliensis ingests skeletal components, and spicules were found inserted in the digestive epithelium. However, this intake is small and apparently does not cause severe injuries to the starfishes and the spicules are discarded in fecal material
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Efeito de treinamento físico e inclusão de levedura viva na dieta sobre a digestibilidade dos nutrientes, parâmetros fisiológicos, de saúde digestiva e condicionamento físico de cavalos Puro Sangue Árabe / Physical training effect and inclusion of live yeast in the diet on digestibility of nutrients, physiological health, digestive parameters and physical conditioning in Arabian horsesCosta, Regina de Lima 18 December 2015 (has links)
O objetivo do presente estudo foi investigar as implicações da suplementação com levedura viva Saccharomyces cerevisiae e de um programa de treinamento físico de baixa intensidade sobre a digestibilidade dos componentes da dieta (MS, PB, EE, FDN, FDA, MO e amido), a resposta glicêmica e insulinêmica, perfil sérico de triglicerídeos, colesterol total e frações (HDL-C; LDL-C; VLDL-C), bem como mensurar a produção dos ácidos graxos de cadeia curta (AGCC) butírico, acético e propiônico, quantificar levedura viva nas fezes, avaliar o pH fecal, a população microbiana nas fezes e os níveis séricos de endotoxinas, além de mensurar a frequência cardíaca dos animais em exercício físico e na recuperação. Foram utilizados dez cavalos da raça Puro Sangue Árabe, machos, castrados, com idade média 72±7,5 meses e peso médio de 473±34,75 kg, alojados em baias individuais, alimentados com dieta constituída de 2% do PC em MS/dia, divididos em 0,75% de concentrado comercial multiparticulado e 1,25% de feno de gramínea (Cynodon dactylon sp. cv Tifton-85). Os tratamentos foram divididos em controle (sem adição de levedura) e suplementados (adição de 15g/dia de levedura viva Saccharomyces cerevisiae) em uma fase sem exercício e outra fase com exercício físico. O delineamento experimental utilizado foi inteiramente casualizado com esquema fatorial 2x2 e os dados obtidos foram submetidos à análise de variância pelo teste F. Para os coeficientes de digestibilidade observou-se efeito de exercício para os coeficientes de digestibilidade da MS, MO, FDN, FDA e PB (P<0,05). Para a variável EE observou-se interação da inclusão de levedura e exercício físico (P<0,1). O amido não apresentou efeito de tratamentos (P>0,1). Para os níveis plasmáticos de glicose observou-se efeito de exercício (P=0,015). Os níveis séricos de insulina não apresentaram efeito de tratamentos (P>0,1). Para triglicérides e VLDL-C não foi observado efeito de tratamentos (P>0,1). O CT, HDL-C e LDL-C apresentaram efeito de interação da inclusão de levedura e exercício (P<0,1). Para a produção de AGCC nas fezes com base na matéria original (MO) não houve efeito para os ácidos acético e butírico (P>0,1), no entanto, observou-se efeito da inclusão de levedura na produção do ácido propiônico (P=0,052). A quantificação de levedura viva nas fezes demonstrou efeito de interação da inclusão de levedura e exercício (P<0,001). Os resultados de pH apontaram efeito de interação da inclusão de levedura e exercício físico para as faixas de horário 1 (P=0,050) e 2 (P=0,080) e efeito de exercício para as faixas 3 (P<0,007) e 4 (P=0,001). Os resultados do perfil bacteriano nas fezes apontaram efeito de exercício para Fibrobacter succinogenes (P=0,083) e de interação da inclusão de levedura e exercício para Lactobacillus genus (P=0,020); não foi observado efeito de tratamentos para Ruminococcus flavenfaciens (P>0,1). Para os níveis séricos de endotoxinas, observou-se efeito de interação da inclusão de levedura e exercício (P=0,689). A FC dos animais em exercício demonstrou efeito de tempo durante o exercício (P<0,001). Para a FC de recuperação, foi possível observar interação da inclusão de levedura e exercício físico (P=0,020). A inclusão de levedura viva S. cerevisiae na dieta de equinos influencia a produção de AGCC propiônico. O exercício físico de baixa intensidade influencia os coeficientes de digestibilidade da MS, MO, FDN, FDA e PB, os níveis plasmáticos de glicose e a quantificação de Fibrobacter succinogenes nas fezes. A inclusão de levedura viva S. cerevisiae na dieta e o exercício físico influenciam o coeficiente de digestibilidade do EE, níveis séricos de HDL-C e LDL-C, a quantificação de levedura viva nas fezes, os níveis séricos de endotoxinas, o pH fecal, a quantificação de Lactobacillus genus nas fezes e a frequência cardíaca de recuperação pós-exercício. O tempo de exercício em cada velocidade influencia a frequência cardíaca dos animais durante o exercício físico / The aim of this study was to investigate the implications of supplementation with live yeast Saccharomyces cerevisiae and a low-intensity exercise training program on digestibility of dietary components (DM, CP, EE, NDF, ADF, MO and starch), the glycemic and insulin response, serum profile of triglycerides (TC), total cholesterol and fractions (HDL-C, LDL-C, VLDL-C), measure the production of short chain fatty acids (SCFA) butyric acid, acetic and propionic, quantify yeast live in feces, evaluating faecal pH, microbial population in faeces and serum levels of endotoxins, in addition to measuring the heart rate of the animals exercise and recovery. Ten horses in the Purebred Arabian race, castrated male, mean age 72 ± 7.5 months and average weight of 473 ± 34.75 kg were used, housed in individual pens, fed diet consisting of 2% of the BW in DM / day, divided into 0.75% multiparticulate commercial concentrate and 1.25% grass hay (Cynodon dactylon sp. cv Tifton -85). The treatments were divided into control (no addition of yeast) and supplemented (plus 15 g / day of live yeast Saccharomyces cerevisiae) in one phase and another phase with and without exercise, respectively. The experimental design was completely randomized in a factorial 2x2 and the data were submitted to analysis of variance by F test. For the digestibility coefficients it was observed exercise effect for the digestibility coefficients of DM, OM, NDF, ADF and PB (P<0.05). For the variable EE it was observed interaction of yeast inclusion and exercise (P<0.1). Starch no effect of treatments (P>0.1). For plasma glucose levels it was observed effect of exercise (P=0.015). Serum insulin levels showed no treatment effect (P>0.1). For triglycerides and VLDL-C was not observed treatment effect (P>0.1). The TC, HDL-C and LDL-C showed interaction effect of adding yeast and exercise (P<0.1). For the production of SCFA in the faeces based on this matter (OM) there was no effect for acetic and butyric acids (P>0.1), however, it was observed effect of including yeast in the production of propionic acid (P=0.052). The quantitation of live yeast in the feces demonstrated interaction effect of adding yeast and exercise (P<0.001). The pH values indicated yeast inclusion of the interaction effect and exercise for time range 1 (P=0.050) and 2 (P=0.080) and exercise effect to the time range 3 (P<0.007) and 4 (P=0.001). The results of the bacteriological profile in feces showed exercise effect to Fibrobacter succinogenes (P=0.083) and interaction of the yeast include the genus Lactobacillus and exercise (P=0.020). It wasnt observed for treatment effects Ruminococcus flavenfaciens (P>0.1). For serum levels of endotoxin it was observed interaction effect of adding yeast and exercise (P=0.689). The CF of animals in exercise demonstrated time effect during exercise (P<0.001). For CF recovery, it was observed interaction of yeast inclusion and exercise (P=0.020). The inclusion of live yeast S. cerevisiae in horse\'s diet influences propionic SCFA production. The low-intensity exercise influences the digestibility coefficients of DM, OM, NDF, ADF and PB, the plasma levels of glucose and quantification of F. succinogenes in the stool. The inclusion of live yeast S. cerevisiae in horses diet and exercise influence EE digestibility, serum levels of HDL-C and LDL-C, quantification of live yeast in the stool, serum levels of endotoxin, fecal pH and quantifying the genus Lactobacillus in stool and heart rate of post-exercise recovery. The exercise time at each speed influences the heart rate of the animals during exercise
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Biogas Production from Organic Waste, Meat and FOG by Anaerobic Digestion and Ultimate Sludge DigestibilityUnknown Date (has links)
The anaerobic biodegradability of food waste (FW), meat waste and FOG (fats, oils
and greases) with municipal primary sewage sludge was assessed using a laboratory scale
anaerobic digester and by ultimate sludge digestibility, at mesophilic conditions by varying
the inoculum to feedstock ratio (1:2-1:10) and solids retention time (SRT). Preliminary
analysis assessed the anaerobic digestion of food waste and meat at a biogas production
over 30 days at 1000 mL and 1400 mL, respectively. The maximum methane yield was
0.18 m3/kg VS and 0.50 m3/kg VS for 1:10 in meat and FOG, respectively in 28 days with
56-61% volatile solids of destruction and first order methane generation rate of 0.15 d-1 for
both meat and FOG. The optimal ratio for meat and FOG was determined to be beyond
highest ratio tested (1:10), and longer SRT should be considered to investigate the impact
of feedstock on methane yield. Preliminary modeling suggests that for one 1.74 MG
digester, diverting just 0.6% of the food waste generated in one-third of Palm Beach
County could produce enough methane to power 130-360 homes for one full month. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
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