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Heterogeneous catalysis holds great promise for oxidizing or reducing a range of pollutants in water. A well-recognized, but understudied, barrier to implementing catalytic treatment centers around fouling or aging over time of the catalyst surfaces. To better understand how to study catalyst fouling or aging, we selected a representative bimetallic catalyst (Pd-In supported on Al(2)O(3)), which holds promise to reduce nitrate to innocuous nitrogen gas by-products upon hydrogen addition, and six model solutions (deionized water, tap water, sodium hypochlorite, sodium borohydride, acetic acid, and sodium sulfide). Our novel aging experimental apparatus permitted single-passage of each model solution, separately, though a small packed bed reactor containing replicate bimetallic catalyst “beds” that could be sacrificed weekly for off-line characterization to quantify impacts of fouling or aging. The composition of the model solutions led to the following gradual changes in surface composition, morphology, or catalytic reactivity: (i) formation of passivating species, (ii) decreased catalytic sites due to metal leaching under acid conditions or sulfide poisoning, (iii) dissolution and/or transformation of indium, (iv) formation of new catalytic sites by the introduction of an additional metallic element, and (v) oxidative etching. The model solution water chemistry (solutes, Eh, pH) captured a wide range of conditions likely to be encountered in potable or industrial water treatment. Aging-induced changes altered catalytic activity and provided insights into potential strategies to improve long-term catalyst operations for water treatment.

Biofouling of membrane surfaces poses significant operational challenges and costs for desalination and wastewater reuse applications. Ultraviolet (UV) light can control biofilms while reducing chemical usage and disinfection by-products, but light deliveries to membrane surfaces in spiral wound geometries has been a daunting challenge. Thin and flexible nano-enabled side-emitting optical fibers (SEOFs) are novel light delivery devices that enable disinfection or photocatalytic oxidation by radiating UV light from light-emitting diodes (LEDs). We envision SEOFs as an active membrane spacer to mitigate biofilm formation on reverse osmosis (RO) membranes. A lab-scale RO membrane apparatus equipped with SEOFs allowed comparison of UV-A (photocatalysis-enabled) versus UV-C (direct photolysis disinfection). Compared against systems without any light exposure, systems with UV-C light formed thinner-but denser-biofilms, prevented permeate flux declines due to biofouling, and maintained the highest salt rejection. Results were corroborated by in-situ optical coherence tomography and ex-situ measurements of biofilm growth on the membranes. Transcriptomic analysis showed that UV-C SEOFs down-regulated quorum sensing and surface attachment genes. In contrast, UV-A SEOFs upregulated quorum sensing, surface attachment, and oxidative stress genes, resulting in higher extracellular polymeric substances (EPS) accumulation on membrane surfaces. Overall, SEOFs that deliver a low fluence of UV-C light onto membrane surfaces are a promising non-chemical approach for mitigating biofouling formation on RO membranes.

In this study, MnO2-coated Fe3O4 nanocomposite (Fe3O4@MnO2) was utilized to decompose H2O2 to remove dyes via advanced oxidation processes and adsorptive bubble separation (advanced ABS system). The combination of H2O2 and Fe3O4@MnO2 generated bubbles and formed a stable foam layer in the presence of a surfactant; sodium dodecyl sulfate (SDS) or cetyltrimethylammonium chloride (CTAC), separating dye from the solution. On the basis of radical quenching experiments, electron paramagnetic resonance and X-ray photoelectron spectroscopy analyses, it was confirmed that the MnO2 shell of catalyst was reduced to Mn2O3 by H2O2, generating radicals and oxygen gas for the removal of dyes. In the advanced ABS system, ∙OH and 1O2 were the main radical species and the O2 concentrations of 0.34 and 0.71 mM were increased in the solution and headspace, respectively. The advanced ABS system demonstrated a high removal efficiency of methylene blue (MB) (99.0%) and the removal rate increased with increasing amounts of components (H2O2, catalyst and SDS). Also, the advanced ABS system maintained high removal efficiency of MB at a wide pH range of 3–9. In addition to the anionic surfactant of SDS, CTAC was applied as a cationic surfactant for the advanced ABS of anionic dyes. Lastly, the scale-up system was applied to remediate dye-contaminated river water and industrial wastewater for possible practical applications.

PURPOSE Though regular surveillance of hepatocellular carcinoma (HCC) for high-risk patients is widely recommended, its rate and effectiveness are not clear. The aim of this study is to investigate the actual rate of HCC surveillance and its related factors and to clarify its impact on survival in a Korean HCC cohort. Materials and Methods From 2012 to 2015, 319 newly diagnosed HCC patients were prospectively enrolled at a tertiary hospital. Patient interviews based on a structured questionnaire survey were conducted. Surveillance was defined as liver imaging test ≥ 2 times with at least 3-month interval within 2 years prior to HCC diagnosis. RESULTS Surveillance rate was 39.8%. Of the HCC patients with high-risk factors, only 182 (57.1%) had knowledge for the need for regular surveillance, and 141 (44.2%) had the accurate information about the method (ultrasound-based study). Surveillance group showed a higher proportion of early HCC (p < 0.001) and a longer overall survival (p < 0.001) compared to non-surveillance group. The multivariable Cox regression analysis indicated Child-Pugh class A, history of anti-viral therapy, low serum α-fetoprotein level, non-advanced Barcelona Clinic Liver Cancer stage as independent predictors of overall survival, while regular surveillance was not (p=0.436). CONCLUSION Less than half of the newly diagnosed Korean HCC patients were under surveillance and the accurate perception for the need of HCC surveillance was insufficient. Of those under surveillance, most patients were diagnosed with early stage HCC, which led to the improved survival. Comprehensive efforts to optimize the surveillance program for the target population are warranted.

Background/Aims: Non-selective β-blockers (NSBBs) are used for primary prevention of esophageal variceal hemorrhage (VH) in patients with portal hypertension, but a significant number of patients develop VH while on NSBB therapy. In this study, we sought to determine whether liver volume can predict the risk of primary prophylaxis failure in cirrhotic patients on NSBB therapy. Methods: A retrospective cohort of 309 patients on prophylactic propranolol was analyzed. Liver volume was measured in portal venous phase images of multidetector computed tomography. Predictors of VH were assessed using a Cox proportional hazards model with competing-risks analysis. A nomogram was developed for estimation of the risk of primary prophylaxis failure. Results: During a median follow-up of 36 months, 37 patients on propranolol developed VH. Liver volume index, the ratio of measured-to-expected liver volume, was an independent predictor of VH (adjusted hazard ratio [HR], 2.70; 95% confidence interval [CI], 1.37 to 5.33; p = 0.004) as were the presence of large varices and the absence of ascites. A nomogram-based volume score of > 0.6 was predictive of prophylaxis failure (HR, 7.54; 95% CI, 2.88 to 19.73; p < 0.001). Time-dependent receiver operating characteristic curve analysis revealed that a nomogram-based risk score had significantly better discriminatory power than the North Italian Endoscopy Club index in predicting prophylaxis failure at 6 and 8 years. Conclusions: Liver volume index is an independent predictor of first VH and a nomogram-based volume score stratifies the VH risk in cirrhotic patients on propranolol prophylaxis.

Urea is an added value chemical with wide applications in the industry and agriculture. The release of urea waste to the environment affects ecosystem health despite its low toxicity. Online monitoring of urea for industrial applications and environmental health is an unaddressed challenge. Electroanalytical techniques can be a smart integrated solution for online monitoring if sensors can overcome the major barrier associated with long-term stability. Mixed metal oxides have shown excellent stability in environmental conditions with long lasting operational lives. However, these materials have been barely explored for sensing applications. This work presents a proof of concept that demonstrates the applicability of an indirect electroanalytical quantification method of urea. The use of Ti/RuO2-TiO2-SnO2 dimensional stable anode (DSA®) can provide accurate and sensitive quantification of urea in aqueous samples exploiting the excellent catalytic properties of DSA® on the electrogeneration of active chlorine species. The cathodic reduction of accumulated HClO/ClO− from anodic electrogeneration presented a direct relationship with urea concentration. This novel method can allow urea quantification with a competitive LOD of 1.83 × 10−6 mol L−1 within a linear range of 6.66 × 10−6 to 3.33 × 10−4 mol L−1 of urea concentration.

In this study, a Janus Fe/C3N4 micromotor driven by a chromate-hydrogen peroxide (Cr(VI)/H2O2) redox system was developed and its movement was analyzed. The motion of the micromotor was tracked via nanoparticle tracking analysis (NTA) and the corresponding diffusion coefficients (D) were determined. The NTA results revealed that D = 0 in water in the absence of additives (Cr(VI) or H2O2). The addition of H2O2 resulted in an increase in D from 0 to 12 × 106 nm2 s−1, which further increased to 20 × 106, 26.5 × 106, 29 × 106, and 44 × 106 nm2 s−1 with the addition of 0.5, 1, 2, and 5 ppm of Cr(VI), respectively. Cr(VI) alone did not efficiently propel the Fe/C3N4-based micromotor. Therefore, it was proposed that the Cr(VI)/H2O2 redox system generates O2, which plays a major role in the movement of the C3N4-based micromotor. In addition, the formation of reactive species, such as OH and 1O2, was confirmed through electron spin resonance experiments. The reactive species efficiently degraded sulfamethaxazole (SMX), an organic pollutant, as demonstrated through degradation studies and product analyses. The effects of various parameters, such as H2O2 concentration, Cr(VI) concentration, and initial pH on the movement of micromotor and degradation of SMX were also documented.

Multifunctional zerovalent-iron/platinum (ZVI/Pt) Janus bubble-propelled micromotors with high decontamination efficiency and efficient self-propulsion properties were fabricated by the asymmetric deposition of catalytic platinum (Pt) in one hemisphere of ZVI microspheres. In the ZVI/Pt micromotors–hydrogen peroxide (H2O2) system, ZVI acts as a heterogeneous Fenton-like catalyst for the degradation of organic pollutants, while simultaneously the hemispheric Pt layer catalytically decomposes H2O2 into water and oxygen, thereby resulting in an oxygen-bubble propulsion system. The ZVI/Pt Janus micromotors were bubble-propelled at a high speed of over 200 μm/s in the presence of 5% H2O2. In addition, complete oxidative degradation of methylene blue (MB) occurred in the presence of 5% H2O2 after 60 min of treatment, whereas ZVI microspheres removed only 12% of MB in 60 min. The magnetic controllable and reusable properties of the ZVI/Pt micromotors make the water purification process more attractive and feasib...

In this study, we synthesized a novel perovskite nanomaterial consisting of AgBiO3 nanoparticles (NPs) via an ion-exchange method for remediation of polluted environments. The AgBiO3 NPs could self-produce significant amounts of reactive oxygen species (ROS) without light illumination or any other additional oxidant due to the controllable release of lattice oxygen from the crystalline AgBiO3, resulting in the formation of ROS somehow. The self-produced 1O2, O2•–, and •OH were confirmed by electron spin resonance spectroscopy using a spin trap technique. We found that the AgBiO3 NPs could be reused for the mineraliztion of most recalcitrant organic compounds alone, including Rhodamine B (RhB), phenol, 4-chlorophenol, 2,4-dichlorophenol, and bisphenol A. After the repeated eight cycles of continious treatment of RhB, AgBiO3 NPs still achieved 79% of degradation after 30 min of treatment. Characterization results revealved that the lattice oxygen inside AgBiO3 was activated to form active oxygen (O*), which...

Implications of sulfidized Fe 0 (nFe/FeS) for the abatement of pollutants of various categories are widely established. In this study, degradation of one of the major organic pollutants, benzoic acid (BA), has been performed using persulfate activated with nFe/FeS. Complete degradation of BA and its transformed product, hydroxybenzoic acid, was observed within 6 min. When the degradation was performed at alkaline pH, the degradation decreased to 8% in the case of Fe 0 , but nFe/FeS still showed 100% degradation after 60 min. Iron dissolution and persulfate decomposition in the presence of scavengers showed that both sulfate and hydroxyl radicals were involved in the Fe 0 -persulfate system and that the hydroxyl radicals were the major species in the nFe/FeS-persulfate system. The major degradation pathway of benzoic acid was hydroxylation followed by complete mineralization, as supported by the practical removal of total organic carbons (more than 75% within 15 min). The observed results are promising in using persulfate activated by nFe/FeS for the remediation of various micro-pollutants from a multitude of water sources.

Manganese oxide nanorods with different crystal phases (α-, β-, γ-, and δ-MnO2) were prepared via a mild hydrothermal method, and examined as heterogeneous catalysts for the decomposition of H2O2 into active radicals and concomitant degradation of methylene blue (MB) dye at neutral pH. The catalytic activity of MnO2 nanorods was highly dependent upon their crystal structures, following the order of γ-MnO2 > β-MnO2 > α-MnO2 > δ-MnO2. Complete degradation of MB was achieved with γ-MnO2 in a short duration of 20 min. Furthermore, γ-MnO2 exhibited much higher activity compared to iron-containing nanoparticles (Fe° and Fe3O4) and several reported catalysts in the literature. The observed trend in catalyst performance was discussed in terms of surface area, degree of crystallinity, and exposed facets. It was found that γ-MnO2 showed considerable activity over a broad range of pH and temperature as well as desired reusability for four consecutive cycles. Quenching studies indicated that hydroxyl radicals ( OH) played a major role in the degradation of MB. These results provide important insight into the design of more efficient manganese oxide catalysts for wastewater treatment.

The agglomeration of zero-valent iron nanoparticles (Fe 0 NPs) can significantly decrease the effective surface area of nanoparticles and thus reduce their catalytic performance. To avoid such agglomeration, a two-part Fe 0 NP-immobilization approach was developed: (1) The fabrication of a macroporous alginate substrate (MAS) that provided a large surface area capable of sustaining a high load of stable and well-dispersed Fe 0 NPs (26.06 wt.%). (2) A facile chemical reductive growth procedure to generate Fe 0 NPs (ca. 50–100 nm) that are covalently anchored to the surface of the MAS. The macroporous alginate substrate-supported Fe 0 nanoparticles (Fe 0 NPs/MAS) removed >96.5% of nitrates from an aqueous solution within 30 min, whereas unsupported Fe 0 NPs removed only 44.7% of nitrates over a longer period of time. These results demonstrate that MAS acts in a way to prevent the agglomeration of Fe 0 NPs and, in turn, to promote their redox activity compared to unsupported Fe 0 NPs. On the basis of our experimental results, a grow mechanism of Fe 0 NPs on the MAS was proposed, and potential implications for environmental applications of Fe 0 NPs/MAS were discussed.

In this study, the environmentally benign citric acid (CA) was utilized to improve the aerobic degradation of 4-chlorophenol (4-CP) over bismuth modified nanoscale zero-valent iron (Bi/Fe(0)). The characterization results revealed the existence of bismuth covering on the Fe(0) surface under zero-valent state. And, the Bi/Fe(0)-CA+O2 system performed excellent reactivity in degradation of 4-CP due to the generation of reactive oxygen species (ROS), which was confirmed by electron spin resonance (ESR) spectroscopy. After 30min of reaction, 80% of 4-CP was removed using Bi/Fe(0)-CA+O2 accompanying with high dechlorination rate. The oxidative degradation intermediates were analyzed by HPLC and LC-MS. We found that CA could promote the bismuth-iron system to produce much reactive oxygen species ROS under both aerobic and anaerobic conditions due to its ligand function, which could react with Fe(3+) to form a ligand complex (Fe(III)Cit), accompanying with a considerable production of Fe(2+) and H2O2. This study provides a new strategy for generating ROS on nZVI and suggests its application for the mineralization of many recalcitrant pollutants.

A new nanomaterial, nalidixic acid grafted magnetite (Fe3O4/NA), was synthesized via a chemical reaction with nano sized magnetite particles. The Fe3O4/NA was superparamagnetic at room temperature and could be separated by an external magnetic field. The presence of mercury in groundwater in wide scale industrial areas of the world has been a huge problem and the prepared Fe3O4/NA nanoparticles showed a high adsorption capacity towards Hg(II) as compared to bare magnetite particles. The high adsorption capacity of NA grafted Fe3O4 (9.52 mg g−1) was due to the increased adsorption sites in the magnetite-nalidixic acid (Fe3O4/NA). The sorption equilibrium data obeyed the Langmuir model while kinetic studies demonstrated that the sorption process of Hg(II) followed well the pseudo second order model. Since the Fe3O4/NA showed (over 99.8%) removal of the initial 1000 ppb Hg(II) within 60 min, it should be practically usable for Hg(II) contaminated water. The desorption of Hg(II) loaded on Fe3O4/NA could be successfully achieved with 0.001 M HCl containing 0.3 M thiourea, and the sorbent exhibited excellent reusability.

We report the potential of a sulfidized nanoscale zerovalent iron-persulfate (S-nZVI-PS) system for in situ chemical oxidation (ISCO) of groundwater pollutants. The study was conducted using a sand-filled rectangular box with a permeable reactive barrier of S-nZVI as a facsimile of the ISCO system. Synthetic water contaminated with a target pollutant (reactive black-5, RB-5) was continuously passed through the box. The injection of PS led to the complete removal of RB-5 and the system remained reactive for approximately 12 days. This system has a benefit that the oxidation products of S-nZVI (i.e., Fe3O4, Fe2O3, and FeSO4) can further activate PS to retain its reactivity. In a separate trial, this method exploited oxidation, reduction, adsorption and co-precipitation mechanisms that conspired to remove two different groundwater pollutants- arsenite and 1,4-dioxane. These results confirmed the utility of S-nZVI-PS as a mediator of ISCO processes to degrade groundwater pollutants.

Hydroxylamine (HA), which is a reductant for the heterogeneous catalysts, was used to increase the activation of peroxymonosulfate (PMS) by cobalt ferrite (CoFe2O4) to degrade sulfamethoxazole (SMX). Here we added HA to increase the efficiency of Fe3+/PMS system. The CoFe2O4-PMS system with 0.1 g/L of CoFe2O4, 1 mM of PMS, and 0.1 mM of HA completely removed 20 mg/L of SMX at pH 5 in 120 min. This system showed higher SMX-degradation efficiency than other cobalt oxides and iron oxides. This increased SMX-degradation efficiency was attributed to the inhibition of self-decomposed radicals and the increased Fe3+/Fe2+ and Co2+/Co3+ redox cycles of CoFe2O4 due to the reducing power of HA. Additionally, CoFe2O4 exhibited superb reactivity during six successive degradation cycles when it was applied in a real water system. The degradation mechanism of SMX was assessed using liquid chromatography-mass spectrometry. This study provided a practical and novel strategy for the removal of pharmaceuticals and personal care products (PPCP).

Sulfidized nanoscale zero-valent iron (S-nZVI) is a notable system used for environmental decontamination. However, it is not much effective for the oxidative degradation of certain types of pollutants. Herein, we report that a combination of S-nZVI with citric acid (CA), as a ligand can efficiently degrade a recalcitrant organic pollutant, carbamazepine (CBZ) by an oxidative mechanism. The major reactive species produced in the S-nZVI-CA system was singlet oxygen (1O2, established by means of electron spin resonance (ESR) experiment), which was derived from an initially-formed O2 − which in turn was obtained by reduction of O2 by Fe2+-citrate complex. Density functional theory (DFT) calculations and LC-MS product analyses revealed that the oxidative degradation of CBZ occurred by the electrophilic attack of 1O2. S-nZVI-CA system can also be used to degrade CBZ in real environmental matrices such as river and groundwater without interference from the sample matrices. Thus, this study demonstrates the utility of the S-nZVI-CA system as a suitable precursor of 1O2 in environmental remediation processes.

In this study, MnO

Reductive degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by nanoscale zero-valent iron (nZVI) wasinvestigated to evaluate the feasibility of using it for in-situ groundwater remediation. Batch experiments were conductedto quantify the kinetics and efficiency of RDX removal by nZVI, and to determine the effects of pH, dissolved oxygen(DO), and ionic strength on this process. Experimental results showed that the reduction of RDX by nZVI followedpseudo-first order kinetics with the observed rate constant (k obs ) in the range of 0.0056-0.0192 min −1 . Column tests wereconducted to quantify the removal of RDX by nZVI under real groundwater conditions and evaluate the potential efficacyof nZVI for this purpose in real conditions. In column experiment, RDX removal capacity of nZVI was determined to be82,500 mg/kg nZVI. pH, oxidation-reduction potential (ORP), and DO concentration varied significantly during thecolumn experiments; the occurrence of these changes suggests that monitoring these quantities may be useful in evaluationof the reactivity of nZVI, because the most critical mechanisms for RDX removal are based on the chemical reductionreactions. These results revealed that nZVI can significantly degrade RDX and that use of nZVI could be an effectivemethod for in-situ remediation of RDX-contaminated groundwater.Key words : Nanoscale Zero-Valent Iron, RDX, Column, Groundwater, Reduction

A novel self-assembled bimetallic zero-valent bismuth/iron (Bi/Fe(0)) composite was synthesized, characterized, and used successfully to remove hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from wastewater. To assess the oxidative and reductive reactivities of Bi/Fe(0) nanoparticles (NPs), RDX degradation experiments were conducted in either ambient or anaerobic conditions, respectively. The best RDX degradation was achieved using 4%-Bi/Fe(0) (atomic ratio) NPs. In ambient conditions, concentrations of Fe(2+) ions and H2O2 were lower in the Bi/Fe(0) solution than in the Fe(0) solution; this difference indicates that most Fe(2+) ions and H2O2 reacted to produce hydroxyl radicals (*OH) and superoxide radical anions (O2(*-)), thereby resulting in the remarkable degradation of RDX. In anaerobic conditions, the presence of Bi increased the electron generation rate from the surfaces of the Bi/Fe(0) NPs. This increase was responsible for the excellent reductive degradation of RDX. Based on Density Functional Theory (DFT) calculations, the adsorption of water was endothermic on Fe(0) NPs and exothermic on Bi/Fe(0) NPs. Therefore, only the dissociation reactions of H2O in the Bi/Fe(0) system were spontaneous, and these reactions resulted in the prominent reactivity of the Bi/Fe(0) NPs.

In this study, we synthesized a novel perovskite nanomaterial consisting of AgBiO

Oxygen-releasing alginate beads (ORABs), a new concept of oxygen-releasing compounds (ORCs) designed to overcome some limitations regarding the fast oxygen release rate and the high pH equilibrium of ORCs, were fabricated to promote the stimulation of aerobic biodegradation in anaerobic groundwater. Slow oxygen-releasing rate and maintenance of constant pH were achieved by changing the parameters (ionic radius and valence) related to the cross-linking ions composing ORABs, and the best results were obtained for ORABs cross-linked with Al (Al-ORABs). Furthermore, the mechanism of the improved aerobic biodegradation using Al-ORABs under oxygen-limiting groundwater conditions was elucidated in batch and column studies with 1,4-dioxane and Mycrobacterium sp. PH-06 as a model contaminant and aerobic microbes, respectively. Maximum 1,4-dioxane degradations of 99% and 68.1% were achieved when Al-ORABs were applied in batch and column conditions, respectively, whereas 34.3% and 18% of 1,4-dioxane were degraded without Al-ORABs in batch and column conditions, respectively.

A novel Ag-Bi nanoparticle has been prepared via a facile precipitation approach. The nanoparticle could achieve purification of contaminated water without supplements and exhibited much higher activity compared to other popular nanoparticles (e.g. nZVI). The excellent performance of Ag-Bi was due in part to a large production of ˙OH radicals.

Although alpha-fetoprotein (AFP) is the most widely used biomarker in hepatocellular carcinoma (HCC) surveillance, disease activity may also increase AFP levels in chronic hepatitis B (CHB). Since nucleos(t)ide analog (NA) therapy may reduce not only HBV viral loads and transaminase levels but also the falsely elevated AFP levels in CHB, we tried to determine whether exposure to NA therapy influences AFP performance and whether selective application can optimize the performance of AFP testing in CHB during HCC surveillance. A retrospective cohort of 6,453 CHB patients who received HCC surveillance was constructed from the electronic clinical data warehouse. Covariates of AFP elevation were determined from 53,137 AFP measurements, and covariate-specific receiver operating characteristics regression analysis revealed that albumin levels and exposure to NA therapy were independent determinants of AFP performance. C statistics were largest in patients with albumin levels ≥ 3.7 g/dL who were followed without NA therapy during study period, whereas AFP performance was poorest when tested in patients with NA therapy during study and albumin levels were < 3.7 g/dL (difference in C statics = 0.35, p < 0.0001). Contrary to expectation, CHB patients with current or recent exposure to NA therapy showed poorer performance of AFP during HCC surveillance. Combination of concomitant albumin levels and status of NA therapy can identify subgroup of CHB patients who will show optimized AFP performance.

Background and aim The aim of this study was to determine whether dynamic computed tomography (CT)-measured liver volume predicts the risk of hepatocellular carcinoma (HCC) when the CT scans do not reveal evidence of HCC in chronic hepatitis B (CHB) patients on surveillance. Methods This retrospective multicentre cohort study included 1,246 patients who received entecavir and regular HCC surveillance in three tertiary referral centres in South Korea. Liver volumes were measured on portal venous phase CT images. A nomogram was developed based on Cox independent predictors and externally validated. Time-dependent receiver operating characteristic (ROC) analysis was performed for comparison with previous prediction models. Results Patients who received dynamic CT studies during surveillance had significantly higher risk for HCC compared to patients without CT studies (hazard ratio [HR] = 3.1; p < 0.001). Expected/measured liver volume ratio was an independent predictor of HCC (HR = 4.2; p = 0.002) in addition to age, sex and cirrhosis. The nomogram based on the four predictors discriminated risks for HCC (HR = 4.1 and 6.0 in derivation and validation cohort, respectively, for volume score > 150; p < 0.001). Time-dependent ROC analysis confirmed better performance of the volume score compared to HCC prediction models with conventional predictors (integrated area under curve = 0.758 vs. 0.661–0.712; p < 0.05). Conclusions CT-measured liver volume is an independent predictor of future HCC, and nomogram-based liver volume score may stratify the risks of HCC in CHB patients who showed negative CT findings for HCC during surveillance.

In this study, biogas generated from the anaerobic digestion of animal manure was purified and separated and the hollow fiber membrane was prepared by the phase separation of cellulose triacetate (CTA) method to separate the biogas. The product was used in the experiment because the separation of gas by using a gas permeation rate of the hollow fiber membrane was produced. A hollow fiber gas separation membrane module using the hollow fiber membrane in the test was produced and biogas generated in the anaerobic digester was purified using a gas separation membrane module. The separation and purification of the resulting biogas was generated from the livestock manure. The isolation and purification of the resulting biogas was CH4 94.2 %, CO2 92.0 % and recovery efficiency was CH4 102.1 %, CO2 83.5 %. Siloxane 0.1 PPM or less, H2S 3 PPM or less were fed, Dewpoint -20° C below by controlling the biogas supplied to the gas separation membrane module at this time and the operating pressure of the gas separation membrane module was 4~7Bar, in the range of temperature is 15~45 °C. Therefore, it was separated in a high concentration of CO2 92.0 % CH4 94.2 %, compared to the composition of the biogas (CH4 68 %, CO2 28 %, O2 0.6 %, H2S 1 PPM or less, Balance 2.7 %) before carrying out the separation and purification test of biogas produced in the study using the gas separation membrane module. In addition, the CH4 and CO2 transfer efficiency was maximized and saved in the stainless steel tank.Tropical Agricultural Research Vol. 26 (1): 210 – 216 (2014)

In this study, hierarchical MnO2-coated magnetic nanocomposite (Fe3O4/MnO2) was synthesized by a mild hydrothermal process, and its application for removing heavy metal ions from contaminated water systems was examined. Structural characterization showed that the Fe3O4 nanoparticle core was coated with amorphous MnO2 shell with flowerlike morphology. The as-prepared nanocomposite had a large surface area and high magnetic saturation value, which ensured its good sorption ability and convenience of separation. Fe3O4/MnO2 exhibited a greatly improved removal capacity toward four different heavy metals (Cd(II), Cu(II), Pb(II), and Zn(II)) compared to unmodified Fe3O4 nanoparticles. The adsorption property of Fe3O4/MnO2 was studied with Cd(II) in more detail. The sorption equilibrium data were well fitted to the Langmuir model, and the maximum adsorption capacity toward Cd(II) was 53.2 mg g(-1). Fe3O4/MnO2 retained over 80% of its adsorption capacity under various solution conditions that are typically encountered in natural waters. This nanocomposite was easily recovered and reused through consecutive adsorption-desorption experiments with the assistance of an external magnetic field. Overall, the findings propose that Fe3O4/MnO2 could be used as an effective recyclable adsorbent for heavy metal ions.

Until now, it is unclear that each plaque components is related with long term clinical outcomes. We assessed relationship between plaque compositions and long term clinical outcomes. The study subjects consisted of 339 consecutive patients (mean age, 61.7±12.2 years; 239 males) who underwent

BACKGROUND AND OBJECTIVES Success rates of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have recently been reported to range from 80% to 90%. A better understanding of the pathologic characteristics of the CTO lesion may helpful to improving CTO PCI success rates. We evaluated the CTO lesion in patients with stable angina (SA) by virtual histology-intravascular ultrasound (VH-IVUS). SUBJECTS AND METHODS The study population consisted of 149 consecutive patients with SA underwent VH-IVUS examination. We analyzed demographic and VH-IVUS findings in 22 CTO patients (17 males; mean, 62.3 years old) compared with 127 non-CTO patients (82 males; mean, 61.3 years old). RESULTS A significantly lower ejection fraction (57.6±13.0% vs. 65.4±8.8%, p=0.007) was detected in the CTO group compared with the non-CTO group. Reference vessel lumen area of the proximal and distal segment was significantly less in CTO group than in non-CTO group. The lesion length of the CTO group was significantly longer than those of the non-CTO group (24.4±9.6 mm vs. 17.2±7.4 mm, p

We evaluated discrepancy of calcium detection between gray scale intravascular ultrasound (IVUS) and virtual histology (VH)-IVUS and the association between coronary calcium and plaque composition.Study population consisted of 162 consecutive patients who underwent percutaneous coronary intervention with VH-IVUS study. Subjects were divided into 3 groups based on gray scale IVUS findings; No calcification group (n=50), spotty group (n=56) who had a lesion containing only small calcium deposits within an arc90° and diffuse group (n=56) who had a diffuse calcified lesion with an arc ≥ 90° in ≥ 1 cross-sectional image of the lesion.No calcification group was younger than spotty and diffuse groups (54.4 ± 13.0 years vs. 61.1 ± 10.7 years and 64.2 ± 9.9 years, p=0.011 and p0.001, respectively). No calcification group had some degree of dense calcium (5. 7 ± 6.9 mm(3)) by VH-IVUS analysis. Furthermore, calcified volume by VH-IVUS in no calcification group was similar to those in spotty group (5.7 ± 6.9 mm(3) vs. 5.4 ± 4.4mm(3)). Dense calcium volume was correlated directly with plaque volume (r=0.65, p0.001), fibrous volume (r=0.54, p0.001), fibro-fatty volume (r=0.29, p0.001) and lipid core volume (r=0.77, p0.001). In multiple regression analysis, lipid core volume (β=0.287, 95% confidence interval (CI) 0.187-0.388, p0.001) was an independent predictor of dense calcium volume.This study showed that coronary calcium can be present even if invisible in gray scale IVUS and associated with lipid core volume, which is a characteristic of plaque vulnerability.

Background and Objectives: Hypercholesterolemia is a key factor in the development of atherosclerosis. We sought to evaluate the relation between hypercholesterolemia and plaque composition in patients with coronary artery disease. Subjects and Methods: Study subjects consisted of 323 patients (mean 61.5 years, 226 males) who underwent coronary angiography and virtual histology-intravascular ultrasound examination. Patients were divided into two groups according to total cholesterol level: hypercholesterolemic group (≥200 mg/dL, n=114) and normocholesterolemic group (

Background and Objectives The relationship between the positive remodeling (PR) of a coronary artery and plaque composition has been studied only in a relatively small number of study population or non-culprit lesion. We evaluated the association between coronary plaque composition and coronary artery remodeling in a relatively large number of culprit lesions. Subjects and Methods The study population consisted of 325 consecutive patients with coronary artery disease that underwent intravascular ultrasound-virtual histology examination in a culprit lesion. The remodeling index (RI) was calculated as the lesion external elastic membrane (EEM) area divided by the average reference EEM area. Results The lesions with PR (RI>1.05, n=97, mean RI=1.19±0.12) had a higher fibrous volume/lesion length (3.85±2.12 mm3/mm vs. 3.04±1.79 mm3/mm, p=0.003) and necrotic core volume/lesion length (1.26±0.89 mm3/mm vs. 0.90±0.66 mm3/mm, p=0.001) than those with negative remodeling (NR) (RI

목적: 급성 신우신염은 일측성 신우신염과 양측성 신우 신염으로 침범할 수 있다. 이 연구의 목적은 일측성 급성 신우신염과 양측성 급성 신우신염 사이의 임상상의 차이를 규명하고, 나아가 급성 신 손상 발생에 있어서 차이점이 있는지를 비교 연구해 보기 위함이다. 방법: 2006년 1월부터 2010년 12월까지 급성 신우신염으로 본원에 입원했던 환자 중 CT로 급성 신우신염 병터가 확인된 177명 환자를 대상으로 후향적 조사를 하였다. BUN, sCreatinine, MDRD eGFR, FENa 등을 조사하였으며, 대상을 양측성군과 일측성군으로 분류하였다. 결과: 연구에 포함된 대상은 177명이었으며, 이 중 일측 성군이 130명, 양측성군이 47명이었다. 일측성군과 양측성군사이에서 BUN, sCreatinine, MDRD eGFR 모두 차이를 보였다. 신 기능에 따라 분석하여 급성 신 손상을 받은 환자는 risk 이상이 51명, failure 이상이 6명이었으며, 양측성군에서 일측성군보다 failure 이상의 심한 신부전이 동반되었고(4 vs. 2, p = 0.044), eGFR도 낮고(65.2 vs. 61.7, p = 0.042), FENa는 높았다(0.81 vs. 1.43, p = 0.042). 결론: 양측성 신우신염은 일측성 신우신염에 비해 신 기능의 저하가 두드러졌다. 특히 양측성 신우신염에서 발생한 급성 신 손상은 일측성 신우신염에서 발생한 급성 신 손상보다 신 기능 감소가 심했다. 또한 양측성 신우신염과 일측성 신우신염 사이에서 급성 신 손상의 발생 기전이 서로 다를 수 있음을 알 수 있었다.