This study employs a series of bimetallic IrRu/Al2O3 catalysts with differing Ir:Ru compositions for lean NOx reduction by CO (CO-SCR). Catalytic activity assessments reveal that bimetallic ...IrRu/Al2O3 catalysts exhibit drastically enhanced de-NOx activities in the low-temperature region, compared with monometallic Ir/Al2O3 or Ru/Al2O3 catalysts. Furthermore, additional characterization and kinetic studies are used to elucidate the origin of the superior catalytic activity observed on bimetallic IrRu/Al2O3 catalysts. DRIFTS analyses show different adsorption affinities of the catalysts towards NO and CO, with CO for Ir and NO for Ru, respectively. The possibility of NCO intermediate formation is ruled out, which implies that the reduction of NOx proceeds through the dissociation of NO and the subsequent recombination of surface N species. Kinetic studies show that a monometallic Ir/Al2O3 catalyst favorably adsorbs CO, which acts as an inhibitor for facile NO adsorption and dissociation. However, bimetallic IrRu/Al2O3 catalysts exhibit higher affinity towards the adsorption of NO which, in terms of catalytic activities, would prove to be beneficial. Calculation of the activation energies for NO consumption and CO oxidation suggests that the rate determining step shifts from the dissociation of NO on a monometallic Ir/Al2O3 catalyst, to the removal of surface O with CO on bimetallic IrRu/Al2O3 catalysts. It is anticipated that the facile uptake of surface O through a CO oxidation reaction prevents the catalyst surface from being predominantly covered by CO or O species which could act as a poison, and leads to enhanced adsorption/dissociation of NO, resulting in a higher catalytic activity on the bimetallic IrRu/Al2O3 catalysts.
Semiconducting SnO2 nanowires deposited with Pd and Sn nanoparticles on their surface are shown to be a highly sensitive hydrogen sensor with fast response time at room temperature. Compared with the ...SnO2 nanowire deposited with Pd or Sn nanoparticles alone, the Pd/Sn-deposited SnO2 nanowire exhibits a significant improvement in the sensitivity and reversibility of sensing hydrogen gas in the air at room temperature. Our investigation indicates that two factors are responsible for the synergistic effect of Pd/Sn codeposition on SnO2 nanowires. One is that in the presence of Pd the oxidation of Sn nanoparticles on the surface of the SnO2 nanowire is incomplete leading only to suboxides SnO x (1 ≤ x < 2), and the other is that the surface of the Pd/Sn-deposited SnO2 nanowire is almost perfectly hydrophobic.
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IJS, KILJ, NUK, PNG, UL, UM
Two reactive media zerovalent iron (ZVI, Fisher Fe0) and amorphous hydrous ferric oxide (HFO)-incorporated porous, naturally occurring aluminum silicate diatomite designated as Fe (25%)-diatomite, ...were tested for batch kinetic, pH-controlled differential column batch reactors (DCBRs), in small- and large-scale column tests (about 50 and 900 mL of bed volume) with groundwater from a hazardous waste site containing high concentrations of arsenic (both organic and inorganic species), as well as other toxic or carcinogenic volatile and semivolatile organic compounds (VOC/SVOCs). Granular activated carbon (GAC) was also included as a reactive media since a permeable reactive barrier (PRB) at the subject site would need to address the hazardous VOC/SVOC contamination as well as arsenic. The groundwater contained an extremely high arsenic concentration (341 mg L-1) and the results of ion chromatography and inductively coupled plasma mass spectrometry (IC−ICP−MS) analysis showed that the dominant arsenic species were arsenite (45.1%) and monomethyl arsenic acid (MMAA, 22.7%), while dimethyl arsenic acid (DMAA) and arsenate were only 2.4 and 1.3%, respectively. Based on these proportions of arsenic species and the initial As-to-Fe molar ratio (0.15 molAs molFe -1), batch kinetic tests revealed that the sorption density (0.076 molAs molFe -1) for Fe (25%)-diatomite seems to be less than the expected value (0.086 molAs molFe -1) calculated from the sorption density data reported by Lafferty and Loeppert (Environ. Sci. Technol. 2005, 39, 2120−2127), implying that natural organic matters (NOMs) might play a significant role in reducing arsenic removal efficiency. The results of pH-controlled DCBR tests using different synthetic species of arsenic solution showed that the humic acid inhibited the MMAA removal of Fe (25%)-diatomite more than arsenite. The mixed system of GAC and Fe (25%)-diatomite increased the arsenic sorption speed to more than that of either individual media alone. This increase might be deduced by the fact that the addition of GAC could enhance arsenic removal performance of Fe (25%)-diatomite through removing comparably high portions of NOMs. Small- and large-scale column studies demonstrated that the empty bed contact time (EBCT) significantly affected sorpton capacities at breakthrough (C = 0.5 C 0) for the Fe0/sand (50/50, w/w) mixture, but not for GAC preloaded Fe (25%)-diatomite. In the large-scale column tests with actual groundwater conditions, the GAC preloaded Fe (25%)-diatomite effectively reduced arsenic to below 50 μg L-1 for 44 days; additionally, most species of VOC/SVOCs were also simultaneously attenuated to levels below detection.
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IJS, KILJ, NUK, PNG, UL, UM
The relationship between early life factors and childhood pulmonary function and structure in preterm infants remains unclear.
This study investigated the impact of bronchopulmonary dysplasia (BPD) ...and perinatal factors on childhood pulmonary function and structure.
This longitudinal cohort study included preterm participants aged ≥5 years born between 2005 and 2015. The children were grouped by BPD severity according to National Institutes of Health criteria. Pulmonary function tests (PFTs) were performed using spirometry. Chest computed tomography (CT) scans were obtained and scored for hyperaeration or parenchymal lesions. PFT results and chest CT scores were analyzed with perinatal factors.
A total 150 children (66 females) aged 7.7 years (6.4-9.9 years) were categorized into non/mild BPD (n=68), moderate BPD (n=39), and severe BPD (n=43) groups. The median z score for forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC ratio, and forced midexpiratory flow (FEF25%-75%) were significantly lower in the severe versus non/mild BPD group (-1.24 vs. -0.18, -0.22 vs. 0.41, -1.80 vs. -1.12, and -1.88 vs. -1.00, respectively; all P<0.05). The median z scores of FEV1, FEV1/ FVC, and FEF25%-75% among asymptomatic patients were also significantly lower in the severe versus non/mild BPD group (-0.82 vs. 0.09, -1.68 vs. -0.87, -1.59 vs. -0.61, respectively; all P<0.05). The severe BPD group had a higher median (range) CT score than the non/mild BPD group (6 0-12 vs. 1 0-10, P<0.001). Prenatal oligohydramnios was strongly associated with both low pulmonary function (FEV1/FVC<lower limit of normal; odds ratio, 3.54) and high CT score (median difference, 2.54).
School-aged children with severe BPD showed airflow limitations and structural abnormalities despite no subjective respiratory symptoms. These results suggest that patients with a history of prenatal oligohydramnios or prolonged mechanical ventilation require extended follow-up.
PURPOSEAtrial fibrillation (AF) patients with low to intermediate risk, defined as non-gender CHA2DS2-VASc score of 0-1, are still at risk of stroke. This study verified the usefulness of ABCD score ...age (≥60 years), B-type natriuretic peptide (BNP) or N-terminal pro-BNP (≥300 pg/mL), creatinine clearance (<50 mL/min/1.73 m²), and dimension of the left atrium (≥45 mm) for stroke risk stratification in non-gender CHA2DS2-VASc score 0-1. MATERIALS AND METHODSThis multi-center cohort study retrospectively analyzed AF patients with non-gender CHA2DS2-VASc score 0-1. The primary endpoint was the incidence of stroke with or without antithrombotic therapy (ATT). An ABCD score was validated. RESULTSOverall, 2694 patients 56.3±9.5 years; female, 726 (26.9%) were followed-up for 4.0±2.8 years. The overall stroke rate was 0.84/100 person-years (P-Y), stratified as follows: 0.46/100 P-Y for an ABCD score of 0; 1.02/100 P-Y for an ABCD score ≥1. The ABCD score was superior to non-gender CHA2DS2-VASc score in the stroke risk stratification (C-index=0.618, p=0.015; net reclassification improvement=0.576, p=0.040; integrated differential improvement=0.033, p=0.066). ATT was prescribed in 2353 patients (86.5%), and the stroke rate was significantly lower in patients receiving non-vitamin K antagonist oral anticoagulant (NOAC) therapy and an ABCD score ≥1 than in those without ATT (0.44/100 P-Y vs. 1.55/100 P-Y; hazard ratio=0.26, 95% confidence interval 0.11-0.63, p=0.003). CONCLUSIONThe biomarker-based ABCD score demonstrated improved stroke risk stratification in AF patients with non-gender CHA2DS2-VASc score 0-1. Furthermore, NOAC with an ABCD score ≥1 was associated with significantly lower stroke rate in AF patients with non-gender CHA2DS2-VASc score 0-1.
► Toxic effects of fermented Rhus verniciflua stem bark extract were investigated. ► No dead animals and toxic changes were observed in the single dose toxicity study. ► No treatment-related changes ...were observed in the repeated dose toxicity study. ► The approximate lethal dose of the extract was >10,000mg/kg in rats. ► The oral NOAEL of the extract was >5000mg/kg/day in rats of both genders.
Fermented Rhus verniciflua stem bark (FRVSB) extract, an urushiol-free extract of Rhus verniciflua Stokes (RVS) fermented with Fomitella fraxinea, has various biological activities. The present study was carried out to investigate the potential toxicity of the FRVSB extract following single and repeated oral administration to Sprague–Dawley rats. In the single dose toxicity study, the FRVSB extract was administered orally to male and female rats at single doses of 0, 2500, 5000, and 10,000mg/kg. No animals died and no toxic changes were observed in clinical signs, body weight, and necropsy findings during the 15-day period following administration. In the repeated dose toxicity study, the FRVSB extract was administered orally to male and female rats for 90days at doses of 0, 556, 1667, and 5000mg/kg/day. There were no treatment-related adverse effects in clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology at any dose tested. The approximate lethal dose of the FRVSB extract was >10,000mg/kg in both genders, the oral no-observed-adverse-effect level of the FRVSB extract was >5000mg/kg/day in both genders, and no target organs were identified.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We develop a quantum key distribution （QKD） system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a ...plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Major depression has various types of symptoms and disease courses with inconsistent response to monoamine-related antidepressants. Thus, monoamine theory may not be the only pathophysiologic pathway ...relevant to depression. Recently, it has been suggested that regulatory T cell (Treg) is associated with depression. Based on our previous study that showed decreased regulatory T cell (Treg) population following chronic high-dose captopril (CHC, 40 mg/kg/day * 21 days) administration, we examined whether CHC alone can induce depressive-like behaviors in mice even without stressful stimuli. In this study, we found that CHC induced depressive-like behaviors in tail suspension test (TST) and forced swimming test (FST) without systemic illness, while it did not induce anhedonic behavior, anxiety-like behaviors, or sociality-related behavior. The depressive-like behaviors were rescued by either CHC washout or antidepressant. CHC caused reduction in foxp3 and gata3 mRNA expression in the lymph nodes with elevation in plasma IL-1β and IL-6. Interestingly, CHC increased serum angiotensin II level. In the hippocampus, CHC increased TNF-α and IL-6 mRNA expression with microglia activation while reduced glucocorticoid receptor expression. However, CHC did not affect to hippocampal kynurenine pathway, serotonin level, hypothalamic corticotropin-releasing hormone mRNA level, or serum corticosterone level. Consequently, we propose that CHC may induce a specific form of depressive-like behaviors via Treg reduction and microglial activation.
The results of medial open-wedge high tibial osteotomy (MOWHTO) according to age is inconclusive. This study aimed to compare the clinical outcomes and failure of MOWHTO in patients < 55 years and > ...65 years.
Consecutive patients who underwent MOWHTO from July 2009 to August 2020 were retrospectively analyzed. 205 patients were considered for analysis. A 1-to-1 propensity score matched analysis to assess clinical outcomes scores including International Knee Documentation Committee (IKDC) subjective score and Lysholm score, radiologic outcomes, complication, and Total Knee Arthroplasty (TKA) conversion between patients > 65 years and patients < 55 years was performed. Radiologic outcomes included Hip-Knee-Ankle (HKA) angle, Weight Bearing Line ratio (WBLR), posterior tibial slope (PTS), and Insall-Salvati (IS) ratio before and after surgery.
The follow-up period was 50.4 months in patients > 65 years and 55.3 months in patients < 55 years. There was no significant difference in the preoperative and postoperative HKA angle, WBLR, PTS, IS ratio, IKDC score and Lysholm score between the two groups. The arthroscopic evaluation of cartilage did not show any statistically significant differences between the two groups. Regarding Minimal clinically important differences (MCID), in the 26% of the older group exceeded MCID of IKDC score; 45% of the older group exceeded MCID of Lysholm score. In the younger group, 24% exceeded MCID of IKDC score and 35% exceeded MCID of Lysholm score. In older group, there were 7 (11.3%) cases of TKA conversion while no TKA conversion was recorded in the younger group. (P = 0.007) The average time to TKA conversion was 67 months. (42 months to 90 months) Kaplan-Meier analysis revealed that the survival rate was 95.2% at 4 years in the older group.
Similar clinical results were obtained in patients over 65 years of age that were eligible for MOWHTO at minimum 2-year follow-up as in patients under 55 years of age. MOWHTO may be a viable option in older patients if proper indications are met. However, the risk of TKA conversion must be considered preoperatively and discussed with patients.
Cohort study; Level of evidence, 3.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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