Effect of flue gas impurities on CO2 capture performance from flue gas at coal-fired power stations by vacuum swing adsorption

AbstractCO2 capture from major stationary emission sites has been studied widely with the increasing realization of the negative impact of greenhouse gas emissions on climate change. In terms of capture technology, solvent scrubbing, membrane processes and adsorption processes are the major contenders with the latter making significant progress over the last decade due to both improved adsorbent and process design and operation. As is well known, capturing CO2 from flue gases at coal-fired power stations by pressure/vacuum swing adsorption is complicated by the existence of significant amounts of water, SOx, NOx and other impurities, which are detrimental to most commercial CO2 selective-adsorbents. Conventional adsorption-based CO2 capture processes rely on using a pre-treatment stage to remove water, SOx and NOx, which adds considerably to the overall cost. In contrast, we report here an adsorption process developed in our laboratory which directly tackles the untreated flue gas without a separate pre-treatment stage by using a propriety multiple-layered bed comprising different adsorbents. The species CO2, H2O, SOx and NOx are processed in the same column within different function layers optimized according to adsorption properties and process conditions. A fully programmable logic controller (PLC) automated three-column pilot plant was built to perform the study with real-time control and data acquisition conducted through Human Machine Interface/Supervisory Control and Data Acquisition (HMI/SCADA) system. Through running continuous experiments, the effects of impurities on process performance such as CO2 purity, recovery and process power are investigated and reported. This is the first in-depth report of the performance of adsorption based capture plants in the presence of impurities found in real flue gas streams

Pulmonary vascular resistance after cardiopulmonary bypass in infants: Effect on postoperative recovery

AbstractObjective: We sought to define the contemporary clinical effect of increased pulmonary vascular resistance in infants after congenital heart operations with cardiopulmonary bypass. Methods: Fifteen infants (median age, 0.31 years; median weight, 5.1 kg) underwent cardiac operations involving cardiopulmonary bypass (range, 49-147 minutes). Pulmonary vascular resistance was measured in the immediate postoperative period in the intensive care unit by means of the direct Fick principle, with respiratory mass spectrometry to measure oxygen consumption. The effect of ventilation with an inspired oxygen fraction of 0.65, with additional infusion of L -arginine, substance P, and inhaled nitric oxide, was assessed and subsequently correlated with the length of mechanical ventilation from the end of cardiopulmonary bypass to successful extubation. Results: Overall, pulmonary vascular resistance at baseline (11.7 ± 5.6 WU · m2) could be reduced to a minimum of 6.1 ± 3.5 WU · m2. The ventilatory time was 0.86 to 14.9 days (median, 1.75 days) and correlated directly with the lowest pulmonary vascular resistance value achieved during the pulmonary vascular resistance study (r 2 = 0.64, P <.01). The patient subgroup with mechanical ventilation of greater than 2 days had significantly higher pulmonary vascular resistance at all stages of the study protocol, and in this group there was a correlation of cardiopulmonary bypass time and ventilatory support time (r 2 = 0.48, P <.05). Conclusion: Increased pulmonary vascular resistance, either directly or as a surrogate of the systemic inflammatory response after cardiopulmonary bypass, continues to have a significant effect on postoperative recovery of infants after cardiac operations. (J Thorac Cardiovasc Surg 2001;121:1033-9

Prebiotics: Metabolism and Symbiotic Synergy with Probiotics in Promoting Health

Prebiotics are non‐digestible food ingredients that beneficially affect the host by selectively stimulating the growth and activity of probiotic bacteria in the colon. All dietary prebiotics and/or dietary fiber provide the physiological and beneficial effects and, therefore, are considered as essential nutrients. According to the Codex Alimentarius and the Canadian Bureau of Nutritional Sciences, dietary fiber consists of carbohydrates with a degree of polymerization (DP) of three or more that naturally occur in foods of plant origin and that are not digested and absorbed by the small intestine. The same definition goes well along with the term dietary prebiotics. Food and Drug Administration (FDA)|Institute of Medicine (IOM) states that dietary fiber only comes from plant foods and anything else is regarded as “added fiber” or “novel fiber.” Dietary fiber and/dietary prebiotics can be industrially produced for a broad range of food applications. They can also be processed into capsules for the purpose of microencapsulating probiotics. In this chapter, the most recognized physiological and/or beneficial effects of the prebiotics are clarified. New evidence on the concentrations of the short‐chain fatty acids (SCFAs) and their metabolic relationship with better health or disease prevention in the host is provided

A population of deletion mutants and an integrated mapping and exome-seq pipeline for gene discovery in maize

To better understand maize endosperm filling and maturation, we used gamma irradiation of the B73 maize reference line to generate mutants with opaque endosperm and reduced kernel fill phenotypes, and created a population of 1788 lines including 47 Mo17 × F2s showing stable, segregating and viable kernel phenotypes. For molecular characterization of the mutants, we developed a novel functional genomics platform that combined Bulked Segregant RNA and Exome sequencing (BSREx-seq) to map causative mutations and identify candidate genes within mapping intervals. To exemplify the utility of the mutants and provide proof-ofconcept for the bioinformatics platform, we present detailed characterization of line 937; an opaque mutant harboring a 6203-bp in-frame deletion covering six exons within the Opaque-1 gene. In addition, we describe mutant line 146 which contains a 4.8 Kb intra-gene deletion within the Sugary-1 gene and line 916 in which an 8.6 Kb deletion knocks out a Cyclin A2 gene. The publically available algorithm developed in this work improves the identification of causative deletions and its corresponding gaps within mapping peaks. This study demonstrates the utility of gamma irradiation for forward genetics in large non-dense genomes such as maize since deletions often affect single genes. Furthermore, we show how this classical mutagenesis method becomes applicable for functional genomics when combined with state-of-the-art genomics tools

The endothelin antagonist BQ123 reduces pulmonary vascular resistance after surgical intervention for congenital heart disease

AbstractObjective: Postoperative pulmonary hypertension in children after surgical intervention for congenital heart disease has been attributed to failure of the pulmonary endothelium to provide adequate vasodilation. Although we have shown that the impaired vasodilatory component attributable to the l-arginine-nitric oxide pathway is almost completely reversible, a nonrestorable component persists, implying an additional vasoconstrictive mechanism in postoperative pulmonary endothelial dysfunction. In this study of children after surgical intervention for congenital heart disease, we measured endothelin-1 levels and used BQ123, a selective endothelin-A receptor antagonist, together with inhaled nitric oxide to discriminate dysfunctional pulmonary endothelial vasodilation from endothelin-mediated pulmonary vasoconstriction. Methods: All children were examined early after surgical intervention in the intensive care unit. Pulmonary vascular resistance (with respiratory mass spectrometry), as well as arterial and venous endothelin-1 levels (measured by means of a quantitative enzyme-linked immunosorbent assay), were determined in 7 children (age range, 3.3-13.7 months; median age, 6.3 months) with intracardiac shunting defects at baseline and during ventilation with a fraction of inspired oxygen of 0.65, with additional BQ123 (0.1 mg/kg infused over 20 minutes), and with inhaled nitric oxide (20 ppm). Results: Pulmonary vascular resistance decreased from 7.7 ± 3.4 at baseline to 6.1 ± 2.8 Woods units · m−2 (P =.022) at a fraction of inspired oxygen of 0.65 and to 4.7 ± 2.7 Woods units · m−2 (P =.013) during BQ123 infusion. Inhaled nitric oxide had no further effect on pulmonary vascular resistance. Left atrial endothelin-1 levels (1.35-5.12 pg/mL; mean, 2.4 pg/mL) correlated significantly with the decrease in pulmonary vascular resistance in response to BQ123 infusion (r2 = 0.89, P =.003). Conclusion: Postoperative elevation of pulmonary vascular resistance in children after surgical intervention for congenital heart disease is responsive to endothelin-A blockade with BQ123. Increased levels of endothelin-1 predict the response to this therapy, which might become an important addition to the clinical armamentarium in postoperative pulmonary hypertensive disease.J Thorac Cardiovasc Surg 2002;124:435-4

A population of deletion mutants and an integrated mapping and exome-seq pipeline for gene discovery in maize

To better understand maize endosperm filling and maturation, we used gamma irradiation of the B73 maize reference line to generate mutants with opaque endosperm and reduced kernel fill phenotypes, and created a population of 1788 lines including 47 Mo17 × F2s showing stable, segregating and viable kernel phenotypes. For molecular characterization of the mutants, we developed a novel functional genomics platform that combined Bulked Segregant RNA and Exome sequencing (BSREx-seq) to map causative mutations and identify candidate genes within mapping intervals. To exemplify the utility of the mutants and provide proof-ofconcept for the bioinformatics platform, we present detailed characterization of line 937; an opaque mutant harboring a 6203-bp in-frame deletion covering six exons within the Opaque-1 gene. In addition, we describe mutant line 146 which contains a 4.8 Kb intra-gene deletion within the Sugary-1 gene and line 916 in which an 8.6 Kb deletion knocks out a Cyclin A2 gene. The publically available algorithm developed in this work improves the identification of causative deletions and its corresponding gaps within mapping peaks. This study demonstrates the utility of gamma irradiation for forward genetics in large non-dense genomes such as maize since deletions often affect single genes. Furthermore, we show how this classical mutagenesis method becomes applicable for functional genomics when combined with state-of-the-art genomics tools

Effect of stenting and mucosal flap preservation on outcome of endoscopic dacryocystorhinostomy

AIM: To determine the effect of stenting and flap preservation on the outcome of endoscopic dacryocystorhinostomy. METHODS: Retrospective study of all endoscopic dacryocystorhinostomy cases performed between 2007 - 2011 at Hospital Universiti Sains Malaysia. A total of 25 cases with nasolacrimal duct obstruction underwent this procedure. Outcome of endoscopic dacryocystorhinostomy was evaluated based on relief of epiphora and anatomical patency by lacrimal syringing and nasal endoscopy upon follow-up at 1, 6 and 12 months post- op. The outcome was considered to be successful only if all three criteria were fulfilled at one year follow - up post - op. Multiple logistic regression was used to determine the association of stenting and flap creation with a successful outcome. RESULTS: Stents were inserted in 13 cases out of 25, and likewise for flaps. The success rate of endoscopic dacryocystorhinostomy at one year post - op was 64% . There was no significant association of stenting with outcome (P = 0. 694), whereas mucosal flap creation was significantly associated with a better outcome (adjusted OR= 7.926; 95%CI: 1. 172-53. 620, P = 0. 034). The main postoperative complication was adhesions, which occurred in 50% of cases. There was no significant association between stenting or flap preservation with complications. CONCLUSION: Preservation of a mucosal flap is significantly associated with a successful outcome of endoscopic dacryocystorhinostomy in nasolacrimal duct obstruction, while stenting is not. Neither stenting nor mucosal flap creation is significantly associated with complications