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Catalytic ozonation is an effective wastewater purification process. However, the low ozone mass transfer in packed bubble columns leads to low ozone utilization efficiency (OUE), poor organic degradation performance, and high energy consumption. Therefore, there is an urgent need to develop efficient supported catalysts that can enhance mass transfer and performance. However, the reaction mechanism of the support on ozone mass transfer remains unclear, which hinders the development of catalytic ozonation applications. In this study, lava rocks (LR)-supported catalysts, specifically CuMn2O4@LR and MnO2Co3O4@LR, were proposed for catalytic ozonation of IBP degradation due to their superior catalytic activity, stability, and high OUE. Addition of CuMn2O4@LR or MnO2Co3O4@LR increased IBP removal efficiency from 85% to 91% or 88%, and reduced energy consumption from 2.86 to 2.14 kWh/m3 or 2.60 kWh/m3, respectively. This improvement was attributed to LR-supported catalysts enhancing mass transfer and promoting O3 decomposition to generate â¢OH and â¢O2-, leading to IBP degradation. Furthermore, this study investigated the effects of ozone dose, supporter sizes, and catalyst components on ozone-liquid mass transfer. The results revealed that the size of the supporter influenced stacked porosity and consequently affected ozone mass transfer. Larger-sized LR (kLa= 0.172 min-1) exhibited better mass transfer compared to smaller-sized supports. Based on these findings, it was concluded that both CuMn2O4@LR and MnO2Co3O4@LR are potential catalysts for catalytic ozonation in residual IBP degradation of pharmaceutical wastewater, and LR showed good credibility as a catalyst supporter. Understanding the effects of supporters and active components on ozone mass transfer provides a fundamental principle for designing supported catalysts in catalytic ozonation applications.
Assuntos
Ibuprofeno , Ozônio , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Ozônio/química , Catálise , Poluentes Químicos da Água/química , Ibuprofeno/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodosRESUMO
The work evaluated the influence of different operating conditions (voltage, ionic strength and mechanical pressure) on algae electro-osmotic dewatering effect and extracellular organic matter (EOM) regionalization. It was found that the algae electro-dewatering effect became better as the voltage and ionic strength increased, but electro-dewatering effect was decreased when ionic strength was more than 0.006gNaCl/gTSS, this indicated that too high ionic strength will reduce algae electro-dewatering effect. In addition, electro-osmosis effect first increases and then weakens when the pressure was increased. The content of dissolved organic materials (DOM) in the filtrate of both electrodes was increased when the voltage and ionic strength enhanced, the DOM content of filtrate at cathode and anode were increased from 42.9 mg/L, 36.7 mg/L to 68.2 mg/L, 85.3 mg/L when ionic strength raised from 0gNaCl/gTSS to 0.01gNaCl/gTSS, this indicated that a large amount of EOM dissolution as the voltage and ionic strength increased. The DOM content of both electrodes did not change significantly when mechanical pressure changed, anodic oxidation can oxidize and decompose macromolecular weight substances into mid-molecular weight and low molecular weight substances.
Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Eletricidade , Eletrodos , Concentração OsmolarRESUMO
OBJECTIVES: Muscle cramps occur in 33% to 78% of patients with dialysis. The etiology of muscle cramps is poorly understood, and no clear evidence-based prevention or treatment strategies exist. Improved interventions are urgently needed. The aim of this study was to investigate the effect of vitamin K2 in reducing the frequency and severity of muscle cramps in hemodialysis (HD) patients. METHODS: This multicenter, randomized, placebo-controlled, crossover clinical trial was conducted from June 2019 to May 2020. Each participant received vitamin K2 (360 µg/d) or placebo for two 4-wk phases, and then crossed to the alternative arm for two 4-wk phases after a 2-wk washout. The primary endpoint was the frequency of muscle cramps during HD. The secondary endpoints were severity and duration of muscle cramps during HD. RESULTS: A total of 523 patients with maintenance HD were screened for muscle cramps, including 41 patients with muscle cramps refractory to conventional interventions, were enrolled. Nineteen patients in the vitamin K2-initial group and 20 in the placebo-initial group completed the protocol, and were included in the final analysis. Vitamin K2 reduced the frequency, duration, and severity of muscle cramps in HD patients (all P < 0.05). The frequency, duration, and severity of muscle cramps in HD patients increased again after crossing over to the placebo. There were no serious adverse events. One patient experienced gastrointestinal discomfort when taking vitamin K2. CONCLUSIONS: This pilot trial demonstrated that vitamin K2 supplementation could decrease the frequency, duration, and severity of muscle cramps in HD patients.
Assuntos
Cãibra Muscular , Diálise Renal , Humanos , Cãibra Muscular/etiologia , Cãibra Muscular/prevenção & controle , Projetos Piloto , Estudos Prospectivos , Diálise Renal/efeitos adversos , Vitamina K 2RESUMO
INTRODUCTION: We performed a meta-analysis to evaluate the influence of a home enteral nutritional support compared with a normal oral diet in postoperative subjects with upper gastrointestinal cancer resection. METHODS: A systematic literature search up to December 2021 was done and 23 studies included 3,010 subjects with upper gastrointestinal cancer resection at the start of the study; 1,556 of them were given home enteral nutritional support and 1,454 were normal oral diet. We calculated the odds ratio (OR) and mean difference (MD) with 95% CIs to evaluate the influence of home enteral nutritional support compared with a normal oral diet in postoperative subjects with upper gastrointestinal cancer resection by the dichotomous or continuous methods with a random or fixed-influence model. RESULTS: Home enteral nutritional support had significantly higher quality of life (MD, 2.08; 95% CI, 1.50-2.67, p < 0.001), better body weight change (MD, 1.87; 95% CI, 1.31-2.43, p < 0.001), higher albumin (MD, 1.27; 95% CI, 0.72-1.82, p < 0.001), and higher pre-albumin (MD, 30.79; 95% CI, 7.29-54.29, p = 0.01) compared to the normal oral diet in subjects with upper gastrointestinal cancer resection. However, home enteral nutritional support had no significant impact on the hemoglobin (MD, 4.64; 95% CI, -4.17 to 13.46, p = 0.30), and complications (OR, 1.03; 95% CI, 0.76-1.40, p = 0.83) compared to the normal oral diet in subjects with upper gastrointestinal cancer resection. CONCLUSIONS: Home enteral nutritional support had a significantly higher quality of life, better body weight change, higher albumin, and higher pre-albumin, and had no significant impact on the hemoglobin and complications compared to the normal oral diet in subjects with upper gastrointestinal cancer resection. Further studies are required.
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BACKGROUND: Vitamin K has long been regarded as a procoagulant drug by physicians, and concerns have been raised with regard to its effects on hemostasis. Although many studies have shown that vitamin K supplementation is safe for thrombotic events, the effect of vitamin K supplementation on the activities of vitamin K dependent procoagulation factors in healthy individuals is not available. OBJECTIVES: This study aimed to investigate whether vitamin K2 supplementation at recommended doses affects the activity of vitamin K dependent procoagulation factors in healthy individuals without any anticoagulation treatment. DESIGN: Forty healthy volunteers between 25 and 40âyears of age were recruited. Menaquinone-7 (MK-7) was administrated at 90âµg for 30âdays. Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and blood coagulation factors II, VII, IX, and X activities and Protein induced by vitamin K absence or antagonist-II (PIVKA-II) were measured on days 0 and 30 after MK-7 administration. RESULTS: PT, APTT, and TT showed no significant differences on day 30 when compared with baseline. The activities of coagulation factors II, VII, IX, and X on day 30 showed no significant differences with those at baseline. PIVKA-II levels were unchanged after 30âdays of MK-7 supplementation. CONCLUSIONS: MK-7 supplementation at recommended dosage does not affect vitamin K-dependent coagulation factors' coagulation activity, and does not enhance the carboxylation of prothrombin in healthy individuals. This indicated that MK-7 administration does not alter hemostatic balance in healthy populations without anticoagulation treatment.
Assuntos
Fatores de Coagulação Sanguínea/efeitos dos fármacos , Suplementos Nutricionais/normas , Vitamina K 2/farmacologia , Adulto , Antifibrinolíticos/farmacologia , Antifibrinolíticos/uso terapêutico , Fatores de Coagulação Sanguínea/análise , Suplementos Nutricionais/estatística & dados numéricos , Fator IX/análise , Fator IX/efeitos dos fármacos , Fator VII/análise , Fator VII/efeitos dos fármacos , Fator X/análise , Fator X/efeitos dos fármacos , Feminino , Voluntários Saudáveis/estatística & dados numéricos , Humanos , Masculino , Tempo de Tromboplastina Parcial/métodos , Tempo de Tromboplastina Parcial/estatística & dados numéricos , Protrombina/análise , Protrombina/efeitos dos fármacos , Tempo de Protrombina/métodos , Tempo de Protrombina/estatística & dados numéricos , Tempo de Trombina/métodos , Tempo de Trombina/estatística & dados numéricos , Vitamina K 2/uso terapêuticoRESUMO
Electro-dewatering (ED) is an attractive technology for enhancing dewaterability of waste activated sludge (WAS), and the distribution and composition of EPS and secondary structure of extracellular protein in sludge has a great influence on the sludge dewaterability. Therefore, in order to optimize and regulate sludge ED process, it is necessary to study the influence of EPS components and composition on the efficiency of sludge ED. In this study, the effects of distribution and composition of EPS and the structure of extracellular proteins on the ED rates and performance were analyzed using eight sludges from different sewage treatment process. The results showed that ED rates at both electrodes were significantly negatively correlated with the concentration of soluble EPS (S-EPS) and loosely bound EPS (LB-EPS), and this correlation was gradually weakened with the in-depth structure of layered EPS structure. High concentration of S-EPS and LB-EPS decreased the initial current and the pH gradient, deteriorating the anodic oxidation and acidification, which affect the release and degradation of EPS. Additionally, the proteins secondary structure can be destroyed and transformed by anodic oxidation and acidification, which can impact the protein water-holding capacity and ED performance.