116 research outputs found
Hydrogen peroxide production in a pilot-scale microbial electrolysis cell
The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.btre.2018.e00276 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/A pilot-scale dual-chamber microbial electrolysis cell (MEC) equipped with a carbon gas-diffusion cathode was evaluated for H2O2 production using acetate medium as the electron donor. To assess the effect of cathodic pH on H2O2 yield, the MEC was tested with an anion exchange membrane (AEM) and a cation exchange membrane (CEM), respectively. The maximum current density reached 0.94–0.96 A/m2 in the MEC at applied voltage of 0.35–1.9 V, regardless of membranes. The highest H2O2 conversion efficiency was only 7.2 ± 0.09% for the CEM-MEC. This low conversion would be due to further H2O2 reduction to H2O on the cathode or H2O2 decomposition in bulk liquid. This low H2O2 conversion indicates that large-scale MECs are not ideal for production of concentrated H2O2 but could be useful for a sustainable in-situ oxidation process in wastewater treatment.Ontario Early Researcher Awar
Upflow anaerobic-microaerobic fixed biofilm reactor integrating methanogenesis with partial nitrification
The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.cej.2018.05.013 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/An anaerobic-microaerobic fixed biofilm (AMFB) reactor, that integrates methanogenesis with partial nitrification within a single unit was investigated to achieve carbon removal simultaneously with ammonium oxidation in dilute wastewater. Membrane aeration was used for a controlled and efficient oxygen supply for partial nitrification and to prevent oxygen related inhibition of methanogens in the AMFB reactor. Removal of chemical oxygen demand (COD) and ammonium oxidation was first tested on synthetic wastewater, followed by domestic wastewater. The COD removal efficiency ranged between 92 and 99% on synthetic wastewater at hydraulic retention time (HRT) of 8–24 h. Nearly complete removal of biochemical oxygen demand (BOD5) was obtained for domestic wastewater. Influent COD was mainly removed by fermentation and methanogenesis, resulting in high methane yields of up to 0.33 LCH4 gCOD−1anaerobic. Ammonium oxidation efficiency of 69–86% was obtained. Microbial community analysis showed proliferation of fermenters and methanogens exclusively in the anaerobic section of the reactor, while aerobic heterotrophs and nitrifiers were mainly identified in the membrane aerated section. This study first proves that the single-stage AMFB reactor can treat municipal wastewater economically to meet the wastewater standards, although further research for improving water quality (e.g., denitrification) would be required.Natural Sciences and Engineering Research Council of Canada, Discovery Gran
Semi-continuous measurement of oxygen demand in wastewater using biofilm-capacitance
The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.biteb.2018.08.009 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/Bio-capacitive coulombs were tested for determination of the 5-day biochemical oxygen demand (BOD5) using a dual-chamber microbial electrochemical cell (MxC) operated at charging (open circuit) and discharging (close circuit) conditions. For acetate medium, the cumulative coulombs charged in a capacitive biofilm anode (open circuit) were well correlated with BOD concentrations (R2 ~ 0.9). The maximum detectable BOD5 concentration with the bio-capacitance MxC was close to 250 mg/L, and the cumulative coulombs were saturated for above the maximum BOD5 concentration (Monod pattern). The bio-capacitance MxC sensor consistently showed high linearity between the cumulative coulombs and BOD5 concentrations for domestic wastewater influent (R2 = 0.93–0.99), despite of 1 min charging. High correlation between the coulombs and BOD5 concentration was also obtained for wastewater effluent at 1 min charging, which indicates that the bio-capacitance MxC sensor can semi-continuously measure BOD5 concentration in wastewater at every 2 min (1 min charging and 1 min discharging).Natural Sciences and Engineering Research Council of Canada Collaborative Research and Development (CRD) Gran
Recent progress of coherent beam combining Kumgang Laser (0.4J@10kHz/10ns)
A coherent beam combining is the most
promising technique to achieve a high output energy
and a high repetition rate laser system with
a good beam quality [1]. It has been demonstrated
experimentally that the coherent beam
combination using self-phase-controlled stimulated
Brillouin scattering phase conjugate mirror
(SC-SBS-PCM) is the simplest coherent beam
combination method [2-3].
For an average output power of a kW range, the
experimental verification of coherent beam combination
is now underway by the Kumgang laser
[4-5]..
Recent progress of coherent beam combining Kumgang Laser (0.4J@10kHz/10ns)
A coherent beam combining is the most
promising technique to achieve a high output energy
and a high repetition rate laser system with
a good beam quality [1]. It has been demonstrated
experimentally that the coherent beam
combination using self-phase-controlled stimulated
Brillouin scattering phase conjugate mirror
(SC-SBS-PCM) is the simplest coherent beam
combination method [2-3].
For an average output power of a kW range, the
experimental verification of coherent beam combination
is now underway by the Kumgang laser
[4-5]..
Imunosni odgovor BALB/c miševa oralno imuniziranih rekombinantnim cjepivom od serovara Salmonella Typhimurium s ugrađenim antigenima enterotoksigenog soja Escherichia coli
Salmonella Typhimurium ghost vaccines containing antigens of enterotoxigenic Escherichia coli (ETEC) were obtained by a strain harboring pMMP184, which carries a ghost cassette. The immune responses of BALB/c mice orally vaccinated with these ghost vaccines were determined in this study. Total IgG against S. Typhimurium were highly detected by the oral immunization route in BALB/c mice. IgGs against ETEC antigens in the ghost cells carrying F41 and intimin were detected at 4 weeks after vaccination. However, FedF elicited a delayed induction of IgGs, whereas FedA immune response failed to or barely induced IgGs after vaccination. Proliferations of CD3e/CD4-T cells were observed in splenocytes of BALB/c mice immunized with S. Typhimurium ghost cells carrying FedF. However, CD45R-B220/CD23-B cells were proliferated by ghost cells carrying FedA, F41, and intimin. The immunized BALB/c mice showed 25~50% protection against challenge with wild type S. Typhimurium, when compared to control mice. Therefore, it is assumed that oral vaccination of S. Typhimurium ghost cells has the potential to protect mice against pathogenic E. coli.Salmonella Typhimurium rekombinantna cjepiva što sadrže antigene enterotoksigenih sojeva Escherichia coli (ETEC) proizvedena su od soja koji posjeduje pMMP184 i nosi rekombinantnu kasetu. Istražen je imunosni odgovor BALB/c miševa oralno cijepljenih tim rekombinantnim cjepivima. Ustanovljena je visoka razina ukupnih IgG za S. Typhimurium nakon oralne imunizacije miševa BALB/c. Imunoglobulini IgG za antigene ETEC u rekombinantnom cjepivu koje sadrži F41 i intimin bili su dokazani četiri tjedna nakon cijepljenja. Ipak, FedF je potaknuo kasnu tvorbu imunoglobulina IgG, dok FedA nije potaknuo ili je potaknuo slab imunosni odgovor nakon cijepljenja. Proliferacija CD3e/CD4-T stanica bila je dokazana u splenocitima miševa BALB/c imuniziranih rekombinantnim cjepivom S. Typhimurium s ugrađenim FedF. Međutim, stanice CD45R-B220/CD23-B proliferirale su nakon cijepljenja rekombinantom FedA, F41 i intimin. Imunizirani miševi BALB/c pokazivali su 25~50% zaštitu nakon izazivačke infekcije serovarom S. Typhimurium u usporedbi s necijepljenim kontrolnim miševima. Stoga se pretpostavlja da oralno cijepljenje s rekombinantnim stanicama serovara S. Typhimurium ima potencijal da zaštiti miševe od infekcije patogenim sojevima E. coli
Enhanced Solubility of the Support in an FDM-Based 3D Printed Structure Using Hydrogen Peroxide under Ultrasonication
Fused deposition modeling (FDM), one of the archetypal 3D printing processes, typically requires support structures matched to printed model parts that principally have undercut or overhung features. Thus, the support removal is an essential postprocessing step after the FDM process. Here, we present an efficient and rapid method to remove the support part of an FDM-manufactured product using the phenomenon of oxidative degradation of hydrogen peroxide. This mechanism was significantly effective on polyvinyl alcohol (PVA), which has been widely used as a support material in the FDM process. Compared to water, hydrogen peroxide provided a two times faster dissolution rate of the PVA material. This could be increased another two times by applying ultrasonication to the solvent. In addition to the rapidness, we confirmed that amount of the support residues removed was enhanced, which was essentially caused by the surface roughness of the FDM-fabricated part. Furthermore, we demonstrated that there was no deterioration with respect to the mechanical properties or shape geometries of the obtained 3D printed parts. Taken together, these results are expected to help enhance the productivity of FDM by reducing the postprocessing time and to allow the removal of complicated and fine support structures, thereby improving the design capability of the FDM technique
The Korean Mistletoe (Viscum album coloratum) Extract Has an Antiobesity Effect and Protects against Hepatic Steatosis in Mice with High-Fat Diet-Induced Obesity
This study investigates the inhibitory effects of Korean mistletoe extract (KME) on adipogenic factors in 3T3-L1 cells and obesity and nonalcoholic fatty liver disease (NAFLD) in mice fed a high-fat diet. Male C57Bl/6 mice fed a high-fat diet were treated with KME (3 g/kg/day) for 15 weeks for the antiobesity and NAFLD experiments. Body weight and daily food intake were measured regularly during the experimental period. The epididymal pad was measured and liver histology was observed. The effects of KME on thermogenesis and endurance capacity were measured. The effects of KME on adipogenic factors were examined in 3T3-L1 cells. Body and epididymal fat pad weights were reduced in KME-treated mice, and histological examination showed an amelioration of fatty liver in KME-treated mice, without an effect on food consumption. KME potently induces mitochondrial activity by activating thermogenesis and improving endurance capacity. KME also inhibited adipogenic factors in vitro. These results demonstrate the inhibitory effects of KME on obesity and NAFLD in mice fed a high-fat diet. The effects appear to be mediated through an enhanced mitochondrial activity. Therefore, KME may be an effective therapeutic candidate for treating obesity and fatty liver caused by a high-fat diet
Flavonoids Isolated from Korea Citrus aurantium L. Induce G2/M Phase Arrest and Apoptosis in Human Gastric Cancer AGS Cells
Aim of the Study. Citrus species is used in traditional medicine as medicinal herb in several Asian countries including Korea. Flavonioids became known as various properties, such as anti-oxidants, anti-inflammation and anti-cancer, and so forth. The present study, the anti-cancer effect of flavonioids isolated from Citrus aurantium L. in human gastric cancer AGS cells has been investigated. Materials and Methods. The anti-proliferative activity was assayed using MTT assay. Cell cycle analysis was done using flow cytometry and apoptosis detection was done using by hoechst fluorescent staining and Annexin V-propidium iodide double staining. Western blot was used to detect the expression of protein related with cell cycle and apoptosis. Results. Flavonoids isolated from Citrus aurantium L. have the effect of anti proliferation on AGS cells with IC50 value of 99 μg/mL. Flavonoids inhibited cell cycle progression in the G2/M phase and decrease expression level of cyclin B1, cdc 2, cdc 25c. Flavonoids induced apoptosis through activate caspase and inactivate PARP. Conclusions. Flavonoids isolated from Citrus aurantium L. induced G2/M phase arrest through the modulation of cell cycle related proteins and apoptosis through activation caspase. These finding suggest flavonoids isolated from Citrus aurantium L. were useful agent for the chemoprevention of gastric cancer
Heme metabolism genes Downregulated in COPD Cachexia.
IntroductionCachexia contributes to increased mortality and reduced quality of life in Chronic Obstructive Pulmonary Disease (COPD) and may be associated with underlying gene expression changes. Our goal was to identify differential gene expression signatures associated with COPD cachexia in current and former smokers.MethodsWe analyzed whole-blood gene expression data from participants with COPD in a discovery cohort (COPDGene, N = 400) and assessed replication (ECLIPSE, N = 114). To approximate the consensus definition using available criteria, cachexia was defined as weight-loss > 5% in the past 12 months or low body mass index (BMI) (< 20 kg/m2) and 1/3 criteria: decreased muscle strength (six-minute walk distance < 350 m), anemia (hemoglobin < 12 g/dl), and low fat-free mass index (FFMI) (< 15 kg/m2 among women and < 17 kg/m2 among men) in COPDGene. In ECLIPSE, cachexia was defined as weight-loss > 5% in the past 12 months or low BMI and 3/5 criteria: decreased muscle strength, anorexia, abnormal biochemistry (anemia or high c-reactive protein (> 5 mg/l)), fatigue, and low FFMI. Differential gene expression was assessed between cachectic and non-cachectic subjects, adjusting for age, sex, white blood cell counts, and technical covariates. Gene set enrichment analysis was performed using MSigDB.ResultsThe prevalence of COPD cachexia was 13.7% in COPDGene and 7.9% in ECLIPSE. Fourteen genes were differentially downregulated in cachectic versus non-cachectic COPD patients in COPDGene (FDR < 0.05) and ECLIPSE (FDR < 0.05).DiscussionSeveral replicated genes regulating heme metabolism were downregulated among participants with COPD cachexia. Impaired heme biosynthesis may contribute to cachexia development through free-iron buildup and oxidative tissue damage
- …