Near-Zero Emissions Oxy-Combustion Flue Gas Purification

The objectives of this project were to carry out an experimental program to enable development and design of near zero emissions (NZE) CO{sub 2} processing unit (CPU) for oxy-combustion plants burning high and low sulfur coals and to perform commercial viability assessment. The NZE CPU was proposed to produce high purity CO{sub 2} from the oxycombustion flue gas, to achieve > 95% CO{sub 2} capture rate and to achieve near zero atmospheric emissions of criteria pollutants. Two SOx/NOx removal technologies were proposed depending on the SOx levels in the flue gas. The activated carbon process was proposed for power plants burning low sulfur coal and the sulfuric acid process was proposed for power plants burning high sulfur coal. For plants burning high sulfur coal, the sulfuric acid process would convert SOx and NOx in to commercial grade sulfuric and nitric acid by-products, thus reducing operating costs associated with SOx/NOx removal. For plants burning low sulfur coal, investment in separate FGD and SCR equipment for producing high purity CO{sub 2} would not be needed. To achieve high CO{sub 2} capture rates, a hybrid process that combines cold box and VPSA (vacuum pressure swing adsorption) was proposed. In the proposed hybrid process, up to 90% of CO{sub 2} in the cold box vent stream would be recovered by CO{sub 2} VPSA and then it would be recycled and mixed with the flue gas stream upstream of the compressor. The overall recovery from the process will be > 95%. The activated carbon process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx, thus exceeding the performance targets of >99% and >95%, respectively. The process was also found to be suitable for power plants burning both low and high sulfur coals. Sulfuric acid process did not meet the performance expectations. Although it could achieve high SOx (>99%) and NOx (>90%) removal efficiencies, it could not produce by-product sulfuric and nitric acids that meet the commercial product specifications. The sulfuric acid will have to be disposed of by neutralization, thus lowering the value of the technology to same level as that of the activated carbon process. Therefore, it was decided to discontinue any further efforts on sulfuric acid process. Because of encouraging results on the activated carbon process, it was decided to add a new subtask on testing this process in a dual bed continuous unit. A 40 days long continuous operation test confirmed the excellent SOx/NOx removal efficiencies achieved in the batch operation. This test also indicated the need for further efforts on optimization of adsorption-regeneration cycle to maintain long term activity of activated carbon material at a higher level. The VPSA process was tested in a pilot unit. It achieved CO{sub 2} recovery of > 95% and CO{sub 2} purity of >80% (by vol.) from simulated cold box feed streams. The overall CO{sub 2} recovery from the cold box VPSA hybrid process was projected to be >99% for plants with low air ingress (2%) and >97% for plants with high air ingress (10%). Economic analysis was performed to assess value of the NZE CPU. The advantage of NZE CPU over conventional CPU is only apparent when CO{sub 2} capture and avoided costs are compared. For greenfield plants, cost of avoided CO{sub 2} and cost of captured CO{sub 2} are generally about 11-14% lower using the NZE CPU compared to using a conventional CPU. For older plants with high air intrusion, the cost of avoided CO{sub 2} and capture CO{sub 2} are about 18-24% lower using the NZE CPU. Lower capture costs for NZE CPU are due to lower capital investment in FGD/SCR and higher CO{sub 2} capture efficiency. In summary, as a result of this project, we now have developed one technology option for NZE CPU based on the activated carbon process and coldbox-VPSA hybrid process. This technology is projected to work for both low and high sulfur coal plants. The NZE CPU technology is projected to achieve near zero stack emissions, produce high purity CO{sub 2} relatively free of trace impurities and achieve ~99% CO{sub 2} capture rate while lowering the CO{sub 2} capture costs

Near-Zero Emissions Oxy-Combustion Flue Gas Purification

The objectives of this project were to carry out an experimental program to enable development and design of near zero emissions (NZE) CO{sub 2} processing unit (CPU) for oxy-combustion plants burning high and low sulfur coals and to perform commercial viability assessment. The NZE CPU was proposed to produce high purity CO{sub 2} from the oxycombustion flue gas, to achieve > 95% CO{sub 2} capture rate and to achieve near zero atmospheric emissions of criteria pollutants. Two SOx/NOx removal technologies were proposed depending on the SOx levels in the flue gas. The activated carbon process was proposed for power plants burning low sulfur coal and the sulfuric acid process was proposed for power plants burning high sulfur coal. For plants burning high sulfur coal, the sulfuric acid process would convert SOx and NOx in to commercial grade sulfuric and nitric acid by-products, thus reducing operating costs associated with SOx/NOx removal. For plants burning low sulfur coal, investment in separate FGD and SCR equipment for producing high purity CO{sub 2} would not be needed. To achieve high CO{sub 2} capture rates, a hybrid process that combines cold box and VPSA (vacuum pressure swing adsorption) was proposed. In the proposed hybrid process, up to 90% of CO{sub 2} in the cold box vent stream would be recovered by CO{sub 2} VPSA and then it would be recycled and mixed with the flue gas stream upstream of the compressor. The overall recovery from the process will be > 95%. The activated carbon process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx, thus exceeding the performance targets of >99% and >95%, respectively. The process was also found to be suitable for power plants burning both low and high sulfur coals. Sulfuric acid process did not meet the performance expectations. Although it could achieve high SOx (>99%) and NOx (>90%) removal efficiencies, it could not produce by-product sulfuric and nitric acids that meet the commercial product specifications. The sulfuric acid will have to be disposed of by neutralization, thus lowering the value of the technology to same level as that of the activated carbon process. Therefore, it was decided to discontinue any further efforts on sulfuric acid process. Because of encouraging results on the activated carbon process, it was decided to add a new subtask on testing this process in a dual bed continuous unit. A 40 days long continuous operation test confirmed the excellent SOx/NOx removal efficiencies achieved in the batch operation. This test also indicated the need for further efforts on optimization of adsorption-regeneration cycle to maintain long term activity of activated carbon material at a higher level. The VPSA process was tested in a pilot unit. It achieved CO{sub 2} recovery of > 95% and CO{sub 2} purity of >80% (by vol.) from simulated cold box feed streams. The overall CO{sub 2} recovery from the cold box VPSA hybrid process was projected to be >99% for plants with low air ingress (2%) and >97% for plants with high air ingress (10%). Economic analysis was performed to assess value of the NZE CPU. The advantage of NZE CPU over conventional CPU is only apparent when CO{sub 2} capture and avoided costs are compared. For greenfield plants, cost of avoided CO{sub 2} and cost of captured CO{sub 2} are generally about 11-14% lower using the NZE CPU compared to using a conventional CPU. For older plants with high air intrusion, the cost of avoided CO{sub 2} and capture CO{sub 2} are about 18-24% lower using the NZE CPU. Lower capture costs for NZE CPU are due to lower capital investment in FGD/SCR and higher CO{sub 2} capture efficiency. In summary, as a result of this project, we now have developed one technology option for NZE CPU based on the activated carbon process and coldbox-VPSA hybrid process. This technology is projected to work for both low and high sulfur coal plants. The NZE CPU technology is projected to achieve near zero stack emissions, produce high purity CO{sub 2} relatively free of trace impurities and achieve ~99% CO{sub 2} capture rate while lowering the CO{sub 2} capture costs

Evidence based development of bedside clinical drug rules for surgical patients

Surgical adverse events constitute a considerable problem. More than half of in-hospital adverse events are related to a surgical procedure. Medication related events are frequent and partly preventable. Due to the complexity and multidisciplinary nature of the surgical process, patients are at risk for drug related problems. Consistent drug management throughout the process is needed. The aim of this study was to develop an evidence-based bedside tool for drug management decisions during the pre- and postoperative phase of the surgical pathway. Tool development study performed in an academic medical centre in the Netherlands involving an expert panel consisting of a surgeon, a clinical pharmacist and a pharmacologist, all experienced in quality improvement. Relevant medication related problems and critical pharmacotherapeutic decision steps in the surgical process were identified and prioritised by a team of experts. The final selection comprised undesirable effects or unintended outcomes related to surgery (e.g. pain, infection) and comorbidity related hazards (e.g. diabetes, cardiovascular diseases). To guide patient management, a list of bedside surgical drug rules was developed using international evidence-based guidelines. 55 bedside drug rules on 6 drug categories, specifically important for surgical practice, were developed: pain, respiration, infection, diabetes, cardiovascular diseases and anticoagulation. A total of 29 evidence-based guidelines were used to develop the Bedside Surgical Drug Rules tool. This tool consist of practical tables covering management regarding (1) the most commonly used drug categories during surgery, (2) comorbidities that require dosing adjustments and, (3) contra-indicated drugs in the perioperative period. An evidence-based approach provides a practical basis for the development of a bedside tool to alert and assist the care providers in their drug management decisions along the surgical pathwa

Therapeutic efficacy of sonic hedgehog protein in experimental diabetic neuropathy

Orientadora : Drª Lucélia DonattiTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa: Curitiba, 31/07/2014Inclui referências : f. 71-83Resumo: Os peixes que habitam o Oceano Antártico são extremamente adaptados ao frio, sendo seu metabolismo, bioquímico e fisiológico, eficiente em baixas temperaturas. Oscilações sazonais de luminosidade e do suprimento alimentar são também apontados como fatores determinantes da biodiversidade e limitantes da biomassa e da produtividade primária do Oceano Antártico. A tolerância a temperaturas mais altas dos organismos marinhos antárticos tem sido estudada devido à preocupação dos pesquisadores frente ao aquecimento global e da Península Antártica. Os poucos resultados existentes têm demonstrado que esses organismos são extremamente estenotérmicos e que alterações de temperatura podem ser letais. O sistema antioxidante representa um importante marcador de resposta dos organismos submetidos a situações de estresse e alterações de temperatura podem promover a geração de espécies reativas de oxigênio ocasionando danos celulares. Atualmente, a extrema estenotermia dos organismos marinhos antárticos também tem sido estudada através da expressão das proteínas do choque térmico (HSPs). Dentre a família das HSPs, a HSP70 apresenta síntese rápida e significativa diante de diferentes estressores, por isso é uma ferramenta útil para quantificar e prever níveis de estresse em organismos. As coletas e os bioensaios deste trabalho, foram realizados na Baía do Almirantado, Ilha Rei George, no Arquipélago das Shetlands do Sul, Península Antártica, onde se localiza a Estação Antártica Comandante Ferraz (EACF). O presente trabalho tem como objetivo investigar variações nos níveis de HSP70, nos níveis de atividade de várias enzimas antioxidantes (SOD, CAT, GPx, GR e GST) e nos níveis dos marcadores não enzimáticos (GSH, PC e LPO) do estresse oxidativo nos peixes antárticos, Notothenia rossii e Nottohenia coriiceps em condições naturais e de estresse térmico. Para tanto, três capítulos compõem este trabalho, onde o primeiro analisa o efeito da temperatura no metabolismo oxidativo de N. rossii e N. coriiceps; o segundo avalia os níveis de expressão de HSP70 no fígado de N. rossii e N. coriiceps submetidos a estresse térmico e o terceiro analisa ao longo do ano os níveis de atividades dos marcadores de estresse oxidativo em diferentes órgãos de N. rossii e N. coriiceps da Baia do Almirantado, Ilha Rei George, Península Antártica. Palavras-chaves: temperatura, sazonalidade, estresse oxidativo, peixes antárticos, proteína do choque térmico.Abstract: The fish that inhabit the Southern Ocean are highly adapted to the cold, and its metabolism, biochemical and physiological, efficient at low temperatures. Seasonal fluctuations of light and food supply are determinants of biodiversity and limiting biomass and primary productivity of the Southern Ocean. The tolerance to higher temperatures of Antarctic marine organisms have studied due to the concern of researchers against global warming and the Antarctic Peninsula. The few results have demonstrated that these organisms are extremely stenothermal and rapid temperature change can be lethal. The antioxidant system is an important response marker of organisms subjected to stress and temperature changes situations can promote the generation of reactive oxygen species causing cell damage. Currently, the extreme stenothermal of Antarctic marine organisms has studied through the expression of heat shock proteins (HSPs). Among the family of HSPs, the HSP70 has significant and rapid synthesis on different stressors, so it is a useful tool to quantify and predict stress levels in organisms. The experiments of were performed in Admiralty Bay, King George Island, in the Archipelago of the South Shetlands, Antarctic Peninsula, where is the Comandante Ferraz Antarctic Station (EACF). This study aims to investigate variations in the levels of HSP70 in the activity levels of several antioxidant enzymes (SOD, CAT, GPx, GR and GST) and the levels of non-enzymatic markers (GSH, PC and LPO) oxidative stress in Antarctic fish, Notothenia rossii and Nottohenia coriiceps in natural and heat stress conditions. Therefore, three chapters make this work, where the first examines the effect of temperature on the oxidative metabolism of N. rossii and N. coriiceps; the second evaluates the HSP70 expression levels in liver N. rossii and N. coriiceps submited to thermal stress and the third analyzes throughout the year, the activity levels of oxidative stress markers in different tissues of N. rossii and N. coriiceps of Admiralty Bay, King George Island, Antarctic Peninsula. Keywords: temperature, seasonality, oxidative stress, Antarctic fish, heat shock proteins

Therapeutic efficacy of sonic hedgehog protein in experimental diabetic neuropathy

Hedgehog proteins modulate development and patterning of the embryonic nervous system. As expression of desert hedgehog and the hedgehog receptor, patched-1, persist in the postnatal and adult peripheral nerves, the hedgehog pathway may have a role in maturation and maintenance of the peripheral nervous system in normal and disease states. We measured desert hedgehog expression in the peripheral nerve of maturing diabetic rats and found that diabetes caused a significant reduction in desert hedgehog mRNA. Treating diabetic rats with a sonic hedgehog–IgG fusion protein fully restored motor- and sensory-nerve conduction velocities and maintained the axonal caliber of large myelinated fibers. Diabetes-induced deficits in retrograde transport of nerve growth factor and sciatic-nerve levels of calcitonin gene–related product and neuropeptide Y were also ameliorated by treatment with the sonic hedgehog–IgG fusion protein, as was thermal hypoalgesia in the paw. These studies implicate disruption of normal hedgehog function in the etiology of diabetes-induced peripheral-nerve dysfunction and indicate that delivery of exogenous hedgehog proteins may have therapeutic potential for the treatment of diabetic neuropathy

Signatures of T cells as correlates of immunity to Francisella tularensis

Tularemia or vaccination with the live vaccine strain (LVS) of Francisella tularensis confers long-lived cell-mediated immunity. We hypothesized that this immunity depends on polyfunctional memory T cells, i.e., CD4(+) and/or CD8(+) T cells with the capability to simultaneously express several functional markers. Multiparametric flow cytometry, measurement of secreted cytokines, and analysis of lymphocyte proliferation were used to characterize in vitro recall responses of peripheral blood mononuclear cells (PBMC) to killed F. tularensis antigens from the LVS or Schu S4 strains. PBMC responses were compared between individuals who had contracted tularemia, had been vaccinated, or had not been exposed to F. tularensis (naive). Significant differences were detected between either of the immune donor groups and naive individuals for secreted levels of IL-5, IL-6, IL-10, IL-12, IL-13, IFN-gamma, MCP-1, and MIP-1 beta. Expression of IFN-gamma, MIP-1 beta, and CD107a by CD4(+)CD45RO(+) or CD8(+) CD45RO(+) T cells correlated to antigen concentrations. In particular, IFN-gamma and MIP-1 beta strongly discriminated between immune and naive individuals. Only one cytokine, IL-6, discriminated between the two groups of immune individuals. Notably, IL-2- or TNF-alpha-secretion was low. Our results identify functional signatures of T cells that may serve as correlates of immunity and protection against F. tularensis