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BACKGROUND: Few studies assessed myocardial inflammation using Cardiovascular Magnetic Resonance Imaging in Kawasaki disease (KD) patients. PURPOSE: To quantify myocardial edema in KD patients using T2 mapping and explore the independent predictors of T2 values. STUDY TYPE: Prospective. SUBJECTS: Ninety KD patients including 40 in acute phase (26 males, 65.0%) and 50 in chronic phase (34 males, 68.0%). Thirty-one healthy volunteers (21 males, 70.0%). FIELD STRENGTH/SEQUENCE: 3.0 T T2-weighted Turbo Spin Echo-Short Time of Inversion Recovery sequence, True fast imaging with steady precession flash sequence and fast low-angle shot 3D spoiled gradient echo sequence. ASSESSMENT: T2 values were compared among KD groups and controls. STATISTICAL TEST: Student's t test and Fisher's exact test; One-way analysis of variance; Pearson correlation analysis; Receiver operating curve analysis; Multivariable linear regression. RESULTS: Global T2 value of KD patients in acute phase was the highest, followed by those of chronic-phase patients and controls (38.83 ± 2.41 msec vs. 37.55 ± 2.28 msec vs. 36.05 ± 1.64 msec). Regional T2 values showed a same trend. There were no significant differences in global and regional T2 values between KD patients with and without coronary artery (CA) dilation, no matter in acute or chronic phase (all KD patients: P = 0.51, 0.51, 0.53, 0.72; acute KD: P = 0.61, 0.37, 0.33, 0.83; chronic KD: P = 0.65, 0.79, 0.62, 0.79). No significant difference was observed in global T2 values between KD patients with Z score > 5.0 and 2.0 < Z score ≤ 5.0 (P = 0.65). Multivariate analysis demonstrated that stage of disease (ß = -0.123) and heart rate (ß = 0.280) were independently associated with global T2 values. DATA CONCLUSION: The degree of myocardial edema was more severe in acute-phase than in chronic-phase KD patients. Myocardial edema persists in patients regardless of the existence or degree of CA dilation. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.
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Síndrome de Linfonodos Mucocutâneos , Masculino , Criança , Humanos , Estudos Prospectivos , Miocárdio/patologia , Imageamento por Ressonância Magnética/métodos , EdemaRESUMO
The ecological risks of biochar-derived dissolved organic matter (DOM) to soil invertebrates at different organismal levels remains limited. This study comprehensively explored the ecological risks of biochar-derived DOM on earthworm gut through assessments of enzyme activity response, histopathology, gut microbiomes, and metabolomics. Results demonstrated that DOM disturbed the digestive enzymes in earthworm, especially for 10% DOM300 groups. The integrated biomarker response v2 (IBRv2) indicated that the perturbation of earthworm digestive enzymes induced by DOM was both time-dependent and dose-dependent. Pathological observations revealed that 10% DOM300 damaged intestinal epithelium and digestive lumen of earthworms. The significant damage and injury to earthworms caused by DOM300 due to its higher concentrations of heavy metal ions and organic substrates (e.g., toluene, hexane, butanamide, and hexanamide) compared to DOM500 and DOM700. Analysis of 16S rRNA from the gut microbiota showed a significant decrease in genera (Verminephrobacter, Bacillus, and Microbacteriaceae) associated with inflammation, disease, and detoxification processes. Furthermore, 10% DOM300 caused the abnormality of metabolites, such as glutamate, fumaric acid, pyruvate, and citric acid, which were involved in energy metabolism, These findings contributed to improve our understanding of the toxic mechanism of biochar DOM from multiple perspectives.
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Carvão Vegetal , Microbioma Gastrointestinal , Oligoquetos , Poluentes do Solo , Animais , Matéria Orgânica Dissolvida , RNA Ribossômico 16S/genética , Poluentes do Solo/análise , SoloRESUMO
Membrane fouling is a bottleneck issue that hindered the further application of ultrafiltration technology. To alleviate membrane fouling, coagulation-ultrafiltration (C-UF) process using polyaluminum chloride (PACl) and PACl-Al13 with high proportion of Al13O4(OH)247+ as coagulants, respectively, were investigated at various pH conditions. Results indicated that an increase in solution pH contributed to larger floc size and looser floc structure for both PACl and PACl-Al13. It was conducive to the formation of more porous cake, as evidenced by mean pore area and pore area distribution of cake, leading to lower reversible fouling. Furthermore, humic acid (HA) removal presented a trend of first increasing and then decreasing with the increase of pH. The optimal HA removal was achieved at pH 6 regardless of coagulant type, suggesting that the slightest irreversible fouling should be occurred at this point. Interestingly, the irreversible fouling with PACl coagulant achieved a minimum value at pH 9, while the minimal irreversible fouling with PACl-Al13 was observed at pH 6. We speculated that the cake formed by PACl could further intercept HA prior to UF process at alkaline pH. Furthermore, compared with PACl, PACl-Al13 had a stronger charge neutralization ability, thus contributing to more compact floc structure and higher HA removal at various pH conditions. By UF fractionation measurement, higher HA removal for PACl-Al13 was due to higher removal of HA with molecular weight less than 50 kDa.
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Substâncias Húmicas , Membranas Artificiais , Ultrafiltração , Ultrafiltração/métodos , Substâncias Húmicas/análise , Floculação , Hidróxido de Alumínio/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Eliminação de Resíduos Líquidos/métodosRESUMO
Biochar-derived dissolved organic matter (DOM) contains toxic substances that are first released into the soil after biochar application. However, the ecological risks of biochar-derived DOM on soil invertebrate earthworms are unclear. Therefore, this study investigated the ecological risks and toxic mechanisms of sewage sludge biochar (SSB)-derived DOM on the earthworm Eisenia fetida (E. fetida) via microcosm experiments. DOM exposure induced earthworm death, growth inhibition, and cocoon decline. Moreover, DOM, especially the 10% DOM300 (derived from SSB prepared at 300 °C) treatments, disrupted the antioxidant defense response and lysosomal stability in earthworms. Integrated biomarker response v2 (IBRv2) analysis was performed to assess the comprehensive toxicity of DOM in E. fetida, and the results revealed that DOM300 might exert more hazardous effects on earthworms than DOM500 (prepared at 500 °C) and DOM700 (prepared at 700 °C), as revealed by increases in the IBRv2 value of 3.48-18.21. Transcriptome analysis revealed that 10% DOM300 exposure significantly disrupted carbohydrate and protein digestion and absorption and induced endocrine disorder. Interestingly, 10% DOM300 exposure also significantly downregulated the expression of genes involved in signaling pathways, e.g., the P13K-AKT, cGMP-PKG, and ErbB signaling pathways, which are related to cell growth, survival, and metabolism, suggesting that DOM300 might induce neurotoxicity in E. fetida. Altogether, these results may contribute to a better understanding of the toxicity and defense mechanisms of biochar-derived DOM on earthworms, especially during long-term applications, and thus provide guidelines for using biochar as a soil amendment.
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Oligoquetos , Poluentes do Solo , Animais , Matéria Orgânica Dissolvida , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Solo , EsgotosRESUMO
In groundwater environments, the interaction between microbial communities and the hydrogeochemical parameters have been investigated extensively in the past years. However, little is known whether the maximum contamination level (MCL) is a threshold value that dictates the microbial composition. In this study, we analyzed 10 groundwater samples for their nitrate, nitrite, COD and sulfate concentrations, and characterized their microbial compositions using 16 S rRNA based high-throughput sequencing methods. All the 10 samples had oxygen demands higher than the corresponding MCL of China (10 mg L-1); moreover, 4 out of 10 samples also had nitrate concentrations higher than the corresponding MCL, which indicated that the groundwater quality was negatively impacted by anthropogenic activities. Comparing the microbial composition of groundwater that had higher-than-MCL nitrate concentrations to those that had lower-than-MCL nitrate concentrations, no significant differences were detected in communities' richness and diversity. However, the non-metric multi-dimensional analysis suggested that the 4 groundwater samples whose nitrate concentration exceed MCL are distinctly different from those of the rest 6 samples, indicating that MCL does have a significant impact on microbial structures. Pearson's correlation analysis suggested that none of the four analyzed hydrochemical parameters had significant impact on microbial communities' richness and diversity; however, at the genus level, the correlation results suggested that JG30-KM-CM45, Sphingomonas and Rhodococcus are closely correlated with nitrate concentration. The findings of this study deepened our understanding with respect to the relationships between the environmental quality indices and the microbial compositions of groundwater.
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Água Subterrânea , Microbiota , Poluentes Químicos da Água , Nitratos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/análise , ChinaRESUMO
OBJECTIVES: The primary aim was to evaluate risk factors for surgical site infections after anterior cruciate ligament reconstruction (ACLR). The secondary aim was to investigate the surgical site infection incidence rate and the mean time to postoperative surgical site infection symptoms. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Embase and Web of Science were searched from database inception to September 2021 and updated in April 2022. ELIGIBILITY CRITERIA: Quantitative, original studies reporting potential risk factors for surgical site infections after ACLR were included. RESULTS: Twenty-three studies with 3871 infection events from 469 441 ACLRs met the inclusion criteria. Male sex (OR 1.78, p< 0.00001), obesity (OR 1.82, p=0.0005), tobacco use (OR 1.37, p=0.01), diabetes mellitus (OR 3.40, p=0.002), steroid use history (OR 4.80, p<0.00001), previous knee surgery history (OR 3.63, p=0.02), professional athlete (OR 4.56, p=0.02), revision surgery (OR 2.05, p=0.04), hamstring autografts (OR 2.83, p<0.00001), concomitant lateral extra-articular tenodesis (OR 3.92, p=0.0001) and a long operating time (weighted mean difference 8.12, p=0.005) were identified as factors that increased the risk of surgical site infections (superficial and deep) after ACLR. Age, outpatient or inpatient surgery, bone-patellar tendon-bone autografts or allografts and a concomitant meniscus suture did not increase the risk of surgical site infections. The incidence of surgical site infections after ACLR was approximately 1% (95% CI 0.7% to 1.2%). The mean time from surgery to the onset of surgical site infection symptoms was approximately 17.1 days (95% CI 13.2 to 21.0 days). CONCLUSION: Male sex, obesity, tobacco use, diabetes mellitus, steroid use history, previous knee surgery history, professional athletes, revision surgery, hamstring autografts, concomitant lateral extra-articular tenodesis and a long operation time may increase the risk of surgical site infections after ACLR. Although the risk of surgical site infections after ACLR is low, raising awareness and implementing effective preventions for risk factors are priorities for clinicians to reduce the incidence of surgical site infections due to its seriousness.
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Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Masculino , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Enxerto Osso-Tendão Patelar-Osso , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Fatores de Risco , Obesidade/complicações , Esteroides , Lesões do Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/complicações , Articulação do Joelho/cirurgiaRESUMO
In situ combustion of heavy oil is currently the most suitable thermal method that meets energy consumption and carbon dioxide emission requirements for heavy oil recovery. The combustion catalyst needs to perform multiple roles for application; it should be capable of catalyzing heavy oil combustion at high temperatures, as well as be able to migrate in the geological formation for injection. In this work, a hyperbranched polymer composite nanometal fluid was used as the injection vector for a heavy oil in situ combustion catalyst, which enabled the catalyst to rapidly migrate to the surface of the oil phase in porous media and promoted heavy oil cracking deposition at high temperatures. Platinum (Pt) nanoparticles encapsulated with cetyl-hyperbranched poly(amide-amine) (CPAMAM), with high interfacial activity, were synthesized by a facile phase-transfer method; the resulting material is called Pt@CPAMAM. Pt@CPAMAM has good dispersion, and as an aqueous solution, it can reduce the interfacial tension between heavy oil and water. As a catalyst, it can improve the conversion rate during the pyrolysis of heavy oil in a nitrogen atmosphere. The catalyst structure designed in this study is closer to that exhibited in practical geological formation applications, making it a potential method for preparing catalysts for use in heavy oil in situ combustion to resolve the problem of catalyst migration in the geological formation.
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Peracetic acid (PAA) serves as a potent and low-toxic oxidant for contaminant removal. Radical-mediated catalytic PAA oxidation processes are typically non-selective, rendering weakened oxidation efficacy under complex water matrices. Herein, we explored the usage of reduced graphene oxide (rGO) for PAA activation via a non-radical pathway. Outperforming the most catalytic PAA oxidation systems, the rGO-PAA system exhibits near-complete removal of typical micropollutants (MPs) within a short time (<2 min). Non-radical direct electron transfer (DET) from MPs to PAA plays a decisive role in the MP degradation, where accelerated DET is achieved by a higher potential of the rGO-PAA reactive surface complexes. Benefitting from DET, the rGO-PAA system shows robust removal of multiple MPs under complex water matrices and with low toxicity. Notably, in the DET regime, the electrostatic attraction of rGO to both PAA and target MP is a critical prerequisite for achieving efficient oxidation, depending on the conditions of solution pH and MP pKa. A heatmap model building on such an electrostatic interaction is further established as guidance for regulating the performance of the DET-mediated PAA oxidation systems. Overall, our work unveils the imperative role of DET for rGO-activated PAA oxidation, expanding the knowledge of PAA-based water treatment strategies.
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Ácido Peracético , Poluentes Químicos da Água , Elétrons , Grafite , Peróxido de Hidrogênio , OxirreduçãoRESUMO
Hydrothermal treatment (HT) is a pragmatic approach for pretreatment of kitchen waste (KW). This work investigated the effect of hydrothermal pretreatment (HTP) on the deoiling, desalting and liquid substances transformation of KW. The orthogonal test method was used to study the effects of three factors at five levels, including solid to liquid ratio (A1-5), heating time (B1-5) and hydrothermal temperature (C1-5). The results indicated that the floatable oil content was improved significantly after HTP. The highest floatable oil content was 84.54 mL/kg at the hydrothermal condition of 1/1.5, 20 min and 100 °C, which was 2.42 times higher than the control. The maximum desalination ratio (92.66%) was at A5B1C5 (1/2.5, 5 min, 100 °C), which was 4.48 times higher than control group (No.0) (20.67%). The VFAs concentration was the highest (11441.05 mg/kg) at 1/2.5, 5 min and 100 °C, which increased by 711.03% compared to the No.0 (1410.78 mg/kg). In addition, the maximum TOC value was obtained at 53530.84 mg/kg. After HTP, the acetic acid and butyric acid concentrations of the liquid phase increased, while the ethanol concentration decreased. The contents of T,NH4+-N and organic nitrogen in the liquid phase of the HTP system increased, while NO3--N remained at a low level (4.96-20.48 mg/kg). The range and variance analysis showed that the temperature had the greatest effect on the deoiling and the liquid substances transformation of KW among these three factors, followed by solid to liquid ratio and heating time. Based on the orthogonal experiment, the optimal parameters for KW deoiling were A3 (1/1.5), B4 (25 min) and C5 (100 °C). This work provided a reference for the KW deoiling and hence improve the efficient utilization of KW.
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TemperaturaRESUMO
The mechanisms governing interactions among various natural organic matter (NOM) fractions and the subsequently impact on ultrafiltration process have not been systematically studied. In this work, bovine serum albumin (BSA), humic acid (HA), sodium alginate (SA) were applied as model NOM to explore the influence of the interactions among NOM on ultrafiltration process. Results indicated that tryptophan-like fluorescence fraction was the dominant reaction fraction of HA to react with SA and BSA. Different interactions among model NOM not only changed the interception order of fluorescence fractions by ultrafiltration from fulvic acid-like, humic-like and tryptophan-like in BSA/HA mixture to tryptophan-like, humic-like and fulvic acid-like in BSA/HA/SA/kaolin mixture, but also remarkably influence the membrane fouling behavior. In BSA/HA mixture, new-generated aggregates with molecular weight (MW) of 10 kDa could not pass though ultrafiltration membrane and mainly contributed to chemical reversible fouling. In BSA/HA/SA mixture, SA simultaneously reacted with BSA and HA to generate aggregates with larger MW which could be washed down by physical cleaning. In BSA/HA/SA/kaolin mixture, the aggregates with MW of 10 kDa and chemical reversible fouling were disappeared due to the adsorption role of kaolin. These findings could further improve our understanding regarding membrane fouling mechanisms of raw water with different components.
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Ultrafiltração , Purificação da Água , Alginatos/química , Substâncias Húmicas/análise , Caulim/química , Membranas Artificiais , Soroalbumina Bovina/química , Triptofano , Ultrafiltração/métodos , Purificação da Água/métodosRESUMO
High sulphide concentrations can be toxic to denitrifying and desulphurising microorganisms. In this study, bioaugmentation was used to solve this problem. Pseudomonas sp. gs1 can tolerate 400 mg/L sulphide and converts most of the sulphide into elemental sulphur after 4 h. A solid inoculum of Pseudomonas sp. h1 was prepared. Two reactors, that is, one with and one without inoculum, were simultaneously run for 60 days. Bioreactor II to which bacterial inoculum was added reached a good treatment performance on day 3. The elemental sulphur concentration of the effluent was 342.6 mg/L. It was maintained at 245.3-333.8 mg/L during the subsequent operation. In contrast, reactor I without inoculants achieved the same performance on day 50. High-throughput sequencing shows that Pseudomonas and Azoarcus are the dominant genera. The abundance of the genus Pseudomonas and related denitrifying sulphur-oxidising bacteria in reactor I increases with the operation time. This phenomenon was confirmed by testing the sqr and gltA genes. The quantitative fluorescence PCR test also proves that the addition of bacteria leads to a rapid increase in the sulphur oxidation and carbon metabolism of the activated sludge in the reactor.
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Reatores Biológicos , Desnitrificação , Bactérias , Nitratos , Nitrogênio , Esgotos , EnxofreRESUMO
Although the contamination of microplastics (MPs) in groundwater has been anticipated, their occurrence, distribution, and composition require further understanding. In this study, the occurrence and distributions of MPs were investigated in shallow groundwater from an important water source district in Tianjin city of northern China. The abundance, the physical morphology, the chemical composition, and the potential correlations of the determined MPs with human activities were thoroughly characterized. MPs were determined from all ten sampling sites with the abundance ranged between 17.0 ± 2.16 to 44.0 ± 1.63 n/L, revealing the ubiquitous existed MPs contamination. Based on the physical categorization, fiber (44.74%) was the most abundant shape, while blue (31.02%) and transparent (26.09%) were the most prevalent colors. The dominant size of MPs was smaller than 200 µm which accounted for 73.10%. A total of seven types of MPs were determined with polyethylene, polyethylene terephthalate, and polystyrene as the main types, of which, polypropylene showed strong positive correlations with polystyrene, indicating the possible similar sources of them. Besides, the determined MPs in groundwater were greater in areas with the high population density and strong population activity, indicating their high correlation with human activity. The study highlighted the presence of MPs in groundwater of drinking water source in northern China and provided useful information for evaluating the potential ecological effects on water quality safety and human health brought by MPs.
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Água Potável , Água Subterrânea , Poluentes Químicos da Água , China , Monitoramento Ambiental , Humanos , Microplásticos , Plásticos , Poliestirenos , Poluentes Químicos da Água/análiseRESUMO
The response of the denitrification community to long-term antibiotic exposure requires further investigation. Here, the significantly altered denitrifying community structure and function were observed by continuous exposure to 1 mg/L sulfamethoxazole (SMZ) or chlortetracycline (CTC) for 180 d in the expanded granular sludge bed reactors. Thaurea, positively correlated with SMZ and NO3- removal efficiency (NrE), was highly enriched in the SMZ-added reactor, while, Comamons and Acinetobacter were largely inhibited. The acute inhibited and then gradual-recovered NrE (87.17-90.38 %) was observed with highly expressed narG, indicating the adaptability of Thaurea to SMZ. However, the abundance of Thaurea and Comamonas greatly decreased, while Melioribacter and Acinetobacter were largely enriched in the CTC-added reactor. CTC created more serious and continuous inhibition of NO3- reduction (NrE of 64.53-66.95 %), with lowly expressed narG. Improved NO2- reduction capacity was observed in both reactors (70.16-95.42 %) with highly expressed nirS and nosZ, revealing the adaptability of NO2- reduction populations to antibiotics.
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Clortetraciclina , Desnitrificação , Bactérias , Reatores Biológicos , Clortetraciclina/toxicidade , Nitrogênio , Esgotos , Sulfametoxazol/toxicidadeRESUMO
BACKGROUND: So far, little evidence is available for the comprehensive comparison of endoscopic submucosal tunnel dissection (ESTD) with endoscopic submucosal dissection (ESD) for the treatment of superficial neoplasia at esophagogastric junction (EGJ). METHODS: EGJ superficial neoplasia patients with ESTD treatment between January, 2021 and August, 2020 were retrospectively reviewed and individually matched at 1:1 ratio with those with ESD treatment according to lesion size, specimen area and lesion location, forming ESTD and ESD group, respectively. A sample size of 17 patients was collected for each group. Treatment outcomes including resection time, specimen area, and resection speed as well as occurrence of complications were evaluated. RESULTS: Compared with ESD group, ESTD group got shorter resection time (111.00 ± 11.70 min for ESD group vs. 71.59 ± 6.18 min for ESTD group, p = 0.008) and faster section speed (0.23 ± 0.03 cm2/min for ESD group vs. 0.37 ± 0.06 cm2/min for ESTD group, p = 0.012). No complication was found to occur in ESTD group, while 1 patient with MP damage and 1 with delayed bleeding was found in ESD group. CONCLUSION: For the treatment of EGJ superficial neoplasia, ESTD is a safer and more effective and reliable endoscopic technique compared with ESD.
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Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Humanos , Ressecção Endoscópica de Mucosa/métodos , Estudos Retrospectivos , Junção Esofagogástrica/cirurgia , Junção Esofagogástrica/patologia , Neoplasias Esofágicas/patologia , Resultado do TratamentoRESUMO
Wearing surgical masks remains the most effective protective measure against COVID-19 before mass vaccination, but insufficient comfortability and low antibacterial/antiviral activities accelerate the replacement frequency of surgical masks, resulting in large amounts of medical waste. To solve this problem, we report new nanofiber membrane masks with outstanding comfortability and anti-pathogen functionality prepared using fluorinated carbon nanofibers/carbon fiber (F-CNFs/CF). This was used to replace commercial polypropylene (PP) nonwovens as the core layer of face masks. The through-plane and in-plane thermal conductivity of commercial PP nonwovens were only 0.12 and 0.20 W/m K, but the F-CNFs/CF nanofiber membranes reached 0.62 and 5.23 W/m K, which represent enhancements of 380% and 2523%, respectively. The surface temperature of the PP surgical masks was 23.9 â when the wearing time was 15 min, while the F-CNFs/CF nanocomposite fibrous masks reached 27.3 â, displaying stronger heat dissipation. Moreover, the F-CNFs/CF nanofiber membranes displayed excellent electrical conductivity and produced a high-temperature layer that killed viruses and bacteria in the masks. The surface temperature of the F-CNFs/CF nanocomposite fibrous masks reached 69.2 â after being connected to a portable power source for 60 s. Their antibacterial rates were 97.9% and 98.6% against E. coli and S. aureus, respectively, after being connected to a portable power source for 30 min.
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To characterize the impact of reactor configuration and influent loading on elemental sulphur (S0) recovery during denitrification desulfurization, a laboratory-scale expanded granular sludge bed (EGSB) reactor was established under two influent acetate/nitrate/sulphide loadings; the water flow velocity, microbial community, and functional genes at different heights were investigated. There was no S0 generated when acetate/nitrate/sulphide loadings were set to 0.95/0.60/1.05 kg/m3.d (low-loading). Furthermore, there were no typical denitrifying sulphide oxidizing bacteria under this condition, and Syntrophobacter, Anaerolineaceae genera were predominant in the reactor. As the influent loading was doubled (high-loading), S0 recovery increased to 87%; the bacterial distribution was relatively homogeneous with sulphide oxidation genera (Thauera) being predominant. Neither nirK nor sqr genes were detected in the low-loading sample at a height of 50 cm. The sqr/sox ratios of low-loading stage were 2.50 (10 cm), 0.94 (30 cm), and 0 (50 cm), and the ratios of the high-loading stage were 1.38 (10 cm), 1.33 (30 cm), and 1.08 (50 cm). A hydrodynamics analysis indicated that the water flow velocity was homogenous throughout the reactor. Appropriate reactor configuration and operation parameters play an important role in the efficient regulation of S0 recovery during denitrification desulfurization.
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Desnitrificação , Esgotos , Reatores Biológicos , Nitratos , EnxofreRESUMO
An extended activated sludge model (E-ASM2d) was established by including the metabolic processes of double-layer extracellular polymeric substances (EPS) and glycogen-accumulating organisms (GAOs) into the existing ASM2d model for describing and predicting the metabolic processes of the side-stream phosphorus (P) recovery reactor. A sensitivity analysis of model parameters on SPO4(soluble phosphate), XLEPS (loosely-bound EPS), XTEPS (tightly-bound EPS), COD, and SNH4 (soluble ammonia nitrogen) outputs was conducted for identifying influential parameters. The predicted effluent values of COD, ammonia nitrogen (NH4), and P corresponded well with actual measured values and all the model performance coefficient values for COD, NH4, and P were higher than 0.65, implying the E-ASM2d model could accurately simulate the metabolic processes of the side-stream P recovery process under different COD:P ratio conditions. The variations in the mainstream biological P metabolic pathway under different COD:P conditions were investigated by the E-ASM2d model. At COD:P ratios of 30, 20, and 10, the values of fPP,TEPS (fraction of XTEPS in polyphosphate metabolic process) increased from 0.092, 0.094, and 0.096 in the initial phase to 0.107, 0.124, and 0.187 in the side-stream phase, respectively, demonstrating that the fraction of P removal by tightly-bound EPS was improved by the side-stream operation.
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Fósforo , Rios , Reatores Biológicos , Redes e Vias Metabólicas , Nitrogênio , Esgotos , Eliminação de Resíduos LíquidosRESUMO
Thiobacillus sp. H1 was isolated and made into solid bacterial agent. The Thiobacillus sp. H1 agent was dosed into two reactor (all the agent dosed one-time, and multi-dosing bacteria evenly) and run for 40 days, a start-up with no microbial agent bioreactor as control. We found that the operational performance of multi-dosing inoculum reactor was stable, and the amount of elemental sulfur produced remained stable at 143.2-152.3 mg/L. The amount of elemental sulfur generated in the reactor without the addition of the inoculum was gradually increased, and the amount of elemental sulfur generated in the reactor with the inoculum added at one-time was decreased. Two kinds of Thiobacillus gen. and unclassified betaproteobacteria that coordinated the overall community function in the autotrophic denitrification desulfurization system with high-throughput sequencing. The trend of FccAB gene in each bioreactor was similar with the trend of elemental sulfur in the effluent. On the 5th day, the copy number of FccAB in bioreactor II was the highest among the three bioreactors, reaching 11.8 log copies L/g. This study explores the possibility of artificially synthesized denitrifying desulfurization flora in the future.
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Microbiota , Thiobacillus , Processos Autotróficos , Reatores Biológicos , Desnitrificação , Nitratos , Nitrogênio , Thiobacillus/genéticaRESUMO
BACKGROUND: Whether endothelial nitric oxide synthase (eNOS) polymorphisms are implicated in cancer development remains controversial. Therefore, we performed this study to obtain a more conclusive result on associations between eNOS polymorphisms and cancer. METHODS: Literature retrieve was conducted in PubMed, Medline and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: Forty-one studies were enrolled for analyses. Pooled overall analyses showed that rs1799983 (dominant model: pâ¯=â¯0.01; recessive model: pâ¯=â¯0.007; allele model: pâ¯=â¯0.005), rs2070744 (recessive model: pâ¯=â¯0.004) and rs869109213 (recessive model: pâ¯<â¯0.0001; allele model: pâ¯=â¯0.02) polymorphisms were all significantly associated with individual susceptibility to cancer. Further subgroup analyses revealed that rs2070744 and rs869109213 polymorphisms were only significantly associated with individual susceptibility to cancer in Caucasians, whereas the rs1799983 polymorphism was significantly associated with individual susceptibility to cancer in both Caucasians and Asians. CONCLUSIONS: Our findings indicated that rs1799983, rs2070744 and rs869109213 polymorphisms may serve as genetic biomarkers of cancer in certain ethnicities.
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Predisposição Genética para Doença , Neoplasias/genética , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo Genético , Povo Asiático , Humanos , População BrancaRESUMO
A novel chiral derivatization reagent, the N-[1-oxo-5-(triphenylphosphonium)pentyl]- (R)-1,3-thiazolidinyl-4-N-hydroxysuccinimide ester bromide salt (OTPTHE), was developed for the separation and selective detection of chiral DL-amino acids by RP-HPLC analysis. The OTPTHE reacted with DL-amino acids at 60°C maintained for 30 minutes in the presence of 100 mM borate buffer (pH 9.5). The separability of the diastereomeric derivatives was evaluated in terms of the resolution value (Rs) using 13 kinds of DL-amino acids, which were completely separated by reversed-phase chromatography using C18 column at 254 nm. The Rs of the DL-amino acids varied from 1.62 to 2.51. As for the application of the DL-amino acids, the determination of DL-Ser in the human plasma of healthy volunteers was performed based on our developed method. It was shown that linear calibrations were available with high coefficients of correlation (r2 > 0.9997). The limit of detection (S/N = 3) of the DL-Ser enantiomers was 5.0 pmol; the relative standard deviations of the intraday and interday variations were below 4.56%; the accuracy ranged between 95.40%-110.06% and 95.45%-109.80%, respectively; the mean recoveries (%) of the DL-Ser spiked in the human plasma were 99.49%-103.74%. The amounts of DL-Ser in the human plasma of healthy volunteers were determined.