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BES for H2O2 production has great potential in the future due to its high efficiency, energy efficiency, and environmental friendliness because it turns waste into useful chemicals without any energy input.

Seawater is a cost-effective and abundant electrolyte used as an electrode rinse solution to enable optimum utilization of reverse electrodialysis (RED). However, it is associated with several limitations, including the use of precious electrode materials, and its long-term stability must be addressed prior to its application in the field of seawater technology. In this context, a novel RED based on carbon electrodes was designed, and the experimental conditions were optimized for maximizing the harvesting of energy with aquaculture wastewater disinfection and recycling. The power obtained by RED, with a current density of 30 A/m

Decreasing the Pt loading and surface area of the cathode was found to accelerate the hydrogen evolution reaction in microbial electrolysis cells (MEC) at low substrate concentrations. The experimental wire cathode used in this study had a reduced Pt loading of 20 µg Pt/cm2 and only 14% of the surface area of the control disk-type cathode. With the wire cathodes, peak current densities of 33.1 ± 2.3 A/m2 to 30.4 ± 0.5 A/m2 were obtained at substrate concentrations of 0.4 g/L and 1.0 g/L, respectively, which were 5.4 to 6.2 times higher than those obtained with the disk electrode (5.1–5.7 A/m2). The higher cathode overpotentials and higher current densities obtained with the wire electrode compared to those observed with the disk electrode were advantageous for hydrogen recovery, energy recovery efficiencies, and the hydrogen volume produced (8.5 ± 1.2 mL at 0.4 g/L to 23.0 ± 2.2 mL at 1.0 g/L with the wire electrode; 6.8 ± 0.4 mL at 0.4 g/L to 21.8 ± 2.2 mL at 1.0 g/L with the disk electrode). Therefore, the wire electrode, which used only 0.6% of the Pt catalyst amount in typical disk-type electrodes (0.5 mg Pt/cm2), was effective at various substrate concentrations. The results of this study are very promising because the capital cost of the MEC reactors can be greatly reduced if the wire-type electrodes with ultralow Pt loading are utilized in field applications.

The direct integration of two-dimensional nanostructures into macroscopic porous carbon substrates is essential for their practical use in potential applications, which is a big challenge due to the difficulty of securing uniform coating layers. In this work, we demonstrate a very simple and effective method for the direct coating of MoS2 onto the surface of porous carbon structures having nano-sized pores, such as vertically aligned carbon nanotube arrays. A uniform coverage of MoS2 over carbon substrates was achieved by chemical vapor deposition of gaseous species derived from starting precursors in a closed reactor. Transmission electron microscopy images, X-ray diffraction data, and Raman spectra confirmed the formation of highly crystalline MoS2 layers. X-ray photoelectron and energy dispersive X-ray spectroscopies revealed highly uniform MoS2 layers over the whole surface of the carbon substrates. Our approach is also applicable for the synthesis of MoS2/carbon fiber paper (CFP) hybrid structures. The electrochemical tests showed that the as-synthesized MoS2/CFP structures can serve as highly active cathodes for reverse electrodialysis.

High hydrogen production rate and energy recovery were accomplished in a tubular microbial electrolysis cell (MEC) equipped with a robust membrane electrode assembly (MEA). The current and the hydrogen production of non-flexible MEAs, simply fabricated by directly brushing a catalyst on a self-supporting tubular membrane, were compared with those of a typical MEA, where a cathode is physically combined with a membrane. Current of 34 ± 2 mA (1.79 ± 0.05 A/m2) and coulombic efficiency of 98.5 ± 1.0% were achieved in non-flexible MEAs, outperforming the typical MEA under fed-batch mode. The MEA, having a durable coating layer, also showed an enhanced hydrogen production rate and electric energy recovery with values of 0.18 ± 0.03 m3/m3-d and 151.9 ± 1.0%, respectively, even for low strength domestic wastewater (dWW) treatment in the continuous-flow mode. These outcomes were similarly maintained in the case of using seawater, which is a good candidate for an economical and environmentally suitable catholyte.

Despite significant advances in the field applications of reserve electrodialysis (RED) to produce salinity gradient power, net energy production remains an issue owing to limitations such as high energy requirement for high flow rates of feed solutions, and severe fouling and pressure build up when thin spacers are used. Therefore, to maximize the performance and efficiency of energy harvesting in the RED, a cascaded RED stack, with multiple stages between the anode and cathode electrodes, was investigated. In cascaded stacks, 100-cell paired stacks were divided into several stages, so the feed water flowed into the first stage, and the effluent from the first stage was then reused in the next stages. This cascaded stack could overcome the typical drawbacks of RED (large amount of feed water required, intensive pumping energy, and low net energy production). Although 25% of the feed water volume was used in the 4-stage cascaded stack (100-cell-pairs) compared to the conventional stack (100-cell-pairs with a parallel flow operation), much more energy was produced with the 4-stage cascaded stack. The net power density and net specific energy with the 4-stage cascaded stack were the highest at 0.5 cm/s (0.48 W/m2) and 0.25 cm/s (0.06 kWh/m3), respectively. This is very promising for the practical application of RED since feed water volumes can be greatly reduced, which could reduce the burden on the feed water pretreatment step. Consequently, we can build a compact RED plant with smaller pretreatment processes and fewer RED unit stacks.

Reverse electrodialysis (RED), based on non-precious electrodes, was applied to disinfect domestic aquaculture wastewater. It was found that treatment could be achieved either by an anodic reaction of electro-generated sodium hypochlorite (NaClO) or via a cathodic reaction of electro-generated hydrogen peroxide (H2O2). Without circulation, the disinfection rate was sub-optimal and depended on the anodic and cathodic reactions, reaching 82 ± 5% at the anode (0.3–2.9 mg/L of chlorineDPD, pH 3.2 ± 0.4) and 59 ± 7% at the cathode (2.9–8.7 mg/L of H2O2, pH 10.7 ± 0.3). In contrast, a high removal efficiency of ≥99 ± 1% was obtained when anodic and cathodic solutions were circulated due to the synergetic effect between HClO and H2O2 (0.1–2.1 mg/L of chlorineDPD, 3.9–4.9 mg/L of H2O2, pH 7.8 ± 0.2). Both operating modes resulted in a stable power production of 6 ± 0.5 W/m2. These results support the view that RED can offer a cost-effective and energy-efficient option for disinfecting aquaculture wastewater.

This report describes direct seawater electrolysis (DSE) wherein natural seawater is used as a catholyte without filtration or pretreatment; seawater is acidified to a pH of 2 while hydroxide ions are produced at the cathode by the hydrogen evolution reaction (HER). It results from the cooperative effect of hydroxide ions trapped through inorganic precipitation at the cathode and proton flux from water dissociation in a bipolar membrane (BPM; used as a separator). The acidification of the catholyte in the proposed BPM-DSE substantially mitigates cathode passivation, eliminates the requirement of additional processes for treatment of inorganic precipitates dispersed in the catholyte, and reduces the cathode potential ( E c ) required for the HER to enable long-term DSE. The BPM in this system plays a critical role in maintaining the electrolyte concentration, suppressing the chlorine evolution reaction (ClER), and maximizing the oxygen evolution reaction. These findings are expected to suggest a breakthrough toward large-scale operation of DSE that successfully overcomes challenges such as energy consumption, inorganic precipitation, ClER, and corrosion.

The purification of hazardous textile dyeing wastewater has exhibited many challenges because it consists of a complex mixture, including dyestuff, additives, and salts. It is necessary to fabricate membranes with enhanced permeability, fouling resistance, stability, and superior dyes and salts removal from wastewater. Incorporating a highly water stable metal-organic framework (MOFs) into membranes would meet the requirements for the efficient purification of textile wastewater. In this study, nanofiltration (NF) membranes are fabricated by incorporating MIL-100 (Fe) into the chitosan (CS) through film casting technique. The effect of MIL-100 (Fe) loadings on chitosan characterized by FT-IR, XRD, contact angle measurement, FESEM-EDS, XPS, zeta potential, and surface roughness analysis. The membrane characterization confirmed the enhanced surface roughness, pore size, surface charge, and hydrophilicity. The CS/MIL-100 (Fe) membrane exhibited an improved pure water flux from 5 to 52 L/m2h as well as 99% rejection efficiency for cationic methylene blue (MB) and anionic methyl orange (MO). We obtained the rejection efficiency trend for the MB mixed salts in the order of MgSO4 (Mg2+ - 51.6%, SO42− - 52.5%) > Na2SO4 (Na+ - 26.3%, SO42− - 29.3%) > CaCl2 (Ca2+ - 21.4%, Cl− - 23.8%) > NaCl (Na+ - 16.8%, Cl− - 19.2%). In addition, the CS/MIL-100 (Fe) composite membrane showed excellent rejection efficiency and antifouling performances with high recycling stability. These stunning results evidenced that the CS/MIL-100 (Fe) nanofiltration membrane is a promising candidate for removing toxic pollutants in the textile dyeing wastewater.

We report the high-yield and large-area synthesis of a spaghetti-like carbon nanotubes (CNTs) on macroscopic Cu substrates (foil and foam) using a Cu-Sn alloy catalyst. In addition, we investigate the corrosion properties of the as-synthesized CNT/Cu foil system in 0.6 M NaCl solution. Electrochemical analysis showed that the corrosion resistance of the CNT/Cu foil system improved by a factor of ∼100 compared to the as-received Cu foil. Thus, it is concluded that a dense network of CNT was uniformly coated on the Cu foil and this coating functioned as an efficient barrier to corrosion under simulated seawater conditions.

Removal of scale-forming ions (e.g., Ca2 +, Mg2 +) from seawater using a bioelecrochemical system (BES) was investigated in a fed-batch and a continuous mode. In the fed-batch mode, Ca2 + removal with different anolyte buffers at different external resistances (10 Ω and 1 kΩ) was evaluated. As a result, Ca2 + was effectively removed with PBS (phosphate buffer solution) and PIPES (piperazine-N,N′-bis(2-ethanesulfonic acid) buffer solution. However, the removal of Ca2 + with PBS was not solely due to current generated from the anode but also from precipitation induced by combining Ca2 + with phosphate ions transferred from the anode chamber while the removal of Ca2 + with PIPES entirely relies on a cathodic reaction. Continuous removal of Ca2 + and Mg2 + with PIPES was more effective than the fed-batch mode with removal efficiencies of > 97 ± 2% (Ca2 + removal) and 98 ± 1% (Mg2 + removal). The XRD spectra revealed that the precipitates were mainly composed of brucite (Mg(OH)2), calcite, and aragonite (CaCO3). These results indicate that BES could be a promising way to remove scale-forming ions that can promote inorganic fouling in membrane-based processes.

Background/Aims: The aim of this study was to investigate parameters that pre dict radiation-induced liver disease (RILD) following stereotactic body radiother apy (SBRT) in patients with hepatocellular carcinoma (HCC) and to identify the clinical significance of RILD. Methods: We retrospectively reviewed the medical records of 117 HCC patients who were treated by SBRT from March 2011 to February 2015. RILD was defined as elevated liver transaminases more than five times the upper normal limit or a worsening of Child-Pugh (CP) score by 2 within 3 months after SBRT. All patients were assessed at 1 month and every 3 months after SBRT. Results: Median follow-up was 22.5 months (range, 3 to 56) after SBRT. RILD was developed in 29 of the 117 patients (24.7%). On univariate analysis, significant pre dictive factors of RILD were pretreatment CP score (p < 0.001) and normal liver volume (p = 0.002). Multivariate analysis showed that CP score was a significant predictor of RILD (p < 0.001). The incidence of RILD increased above a CP score of 6 remarkably. The rate of recovery from RILD decreased significantly above a CP score of 8. Survival analysis showed that CP score was an independent prog nostic factor of overall survival (p = 0.001). Conclusions: CP score is a significant factor to predict RILD in patients with chronic liver disease. RILD can be tolerated by patients with a CP score ≤ 7. How ever, careful monitoring of liver function is needed for patients with a CP score 7 after SBRT.

Global warming has become a serious threat biosphere and effective measures are required to mitigate its intensification. To this end, carbon capture and sequestration (CCS) is a promising technology, while post-combustion capture (PCC) has been developed from CCS. However, an energy penalty during the regeneration step of the CO2 absorbent has remained a critical problem. In the present study, a lab-scale test was conducted on carbon capture with reverse-electrodialysis (CCRED) to evaluate its potential to overcome the technical and economic drawbacks of CCS and RED. The results show that a normalized peak power density of 1 W/m2, equal to 328.6 kJ/kgCO2, could be obtained. The peak power density was 2000-fold higher than that in previous studies. By utilizing CO2 as an energy source in CCRED, this novel process can compensate for the energy penalty in conventional CCS.

In this work, we demonstrate the large-area synthesis of graphitic filamentous nanocarbon-aligned carbon thin layer (GFNACTL) on Cu foil by chemical vapor deposition of C 2 H 2 at 700 °C at 5 Torr pressure. The thickness of the GFNACTL can be controlled to vary in the range 50–4000 nm by varying the synthesis time. The graphitic filamentous nanocarbon with outer diameters ∼10–20 nm have highly oriented and well-connected graphitic structures that are stacked perpendicular to the growth direction. This result shows that the presence of a native oxide layer on the Cu foil was beneficial for the GFNACTL growth. Our approach can be extended to the one-pot synthesis of GFNACTL/carbon nanotube (CNT) forest hybrid thin films. The tip growth of CNTs with diameters of ∼50 nm was catalyzed on the GFNACTL by Cu 41 Sn 11 nanoparticles. Corrosion measurements were performed in 0.6 M NaCl solution. Electrochemical analysis revealed a strong improvement in corrosion resistance as compared to pure Cu specimens, indicating the superior uniformity and promise of the GFNACTL/CNT forest hybrid thin films for application as a protective coating.

To properly design reverse electrodialysis (RED) stacks, modeling of ion transport and prediction of power generation on the single RED stack are very important. Currently, the Nernst–Planck equation is widely adopted to simulate ion transport through IEMs. However, applying typical Nernst-Planck equation is not proper to analyze ion transport through the heterogeneous thin-composite pore-filling membrane because of the non-conductive site in the membrane matrix. Herein, we firstly introduced modified Nernst-Planck equation by addressing conductive traveling length (CTL) to simulate the ion transport through the thin-composite pore-filling membranes and the performance of a single RED stack with the same membranes. Also, 100 cell-pairs of RED stacks were assembled to validate modified Nernst-Planck equation according to the flow rate and membrane types. Under the OCV condition, the conductivity of the effluents was measured to validate the modified Nernst-Planck equation, and differences between modeling and experiments were less than 1.5 mS/cm. Theoretical OCV and current density were estimated by using modified Nernst-Planck equation. In particular, hydrophobicity on the surface of the heterogeneous membrane was considered to describe ion transport through the pore-filling membranes. Moreover, power generation from RED stacks was calculated according to the flow rate and the number of cell pairs.

In this work, we describe the direct growth of carbon nanofilaments by the catalytic decomposition of ethanol on untreated polycrystalline Ni foil. Our work focuses on the effects of synthesis conditions on the growth of the carbon nanofilaments and their growth mechanism. Direct growth of carbon nanotubes (CNTs) is more favorable on lower-purity Ni foil. The highest yield was obtained at approximately 750 °C. The average diameter of the CNTs was approximately 20–30 nm. Raman spectra revealed that the increase of H2 concentration in the carrier gas and synthesis temperature induced the growth of better-graphitized CNTs. Additionally, we investigated the anticorrosion properties of as-prepared products under simulated seawater conditions. The corrosion rate of the CNT/Ni foil system was maximally 50–60 times slower than that of the as-received Ni foil, indicating that the CNT coating may be a good candidate for corrosion inhibition.

This work investigated the decomposition of aqueous anatoxin-a originated from cyanobacteria using an underwater dielectric barrier discharge plasma system based on a porous ceramic tube and an alternating current (AC) high voltage. Plasmatic gas generated inside the porous ceramic tube was uniformly dispersed in the form of numerous bubbles into the aqueous solution through the micro-pores of the ceramic tube, which allowed an effective contact between the plasmatic gas and the aqueous anatoxin-a solution. Effect of applied voltage, treatment time and the coexistence of nutrients such as , and glucose on the decomposition of anatoxin-a was examined. Chemical analyses of the plasma-treated anatoxin-a solution using liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC) were performed to elucidate the mineralization mechanisms. Increasing the voltage improved the anatoxin-a decomposition efficiency due to the increased discharge power, but the energy required to remove a given amount of anatoxin-a was similar, regardless of the voltage. At an applied voltage of 17.2 kV (oxygen flow rate: ), anatoxin-a at an initial concentration of (volume: 0.5 L) was successfully treated within 3 min. The chemical analyses using LC-MS and IC suggested that the intermediates with molecular weights of 123~161 produced by the attack of plasma-induced reactive species on anatoxin-a molecule were further oxidized to stable compounds such as acetic acid, formic acid and oxalic acid.

Purpose The purpose of this study is to determine whether breast cancer subtype can affect locoregional recurrence (LRR) and ipsilateral breast tumor recurrence (IBTR) after neoadjuvant chemotherapy (NAC) and breast-conserving therapy (BCT). Materials and Methods We evaluated 335 consecutive patients with clinical stage II-III breast cancer who received NAC plus BCT from 2002 to 2009. Patients were classified according to six molecular subtypes: luminal A (hormone receptor [HR]+/HER2–/Ki-67 < 15%, n=113), luminal B1 (HR+/HER2–/Ki-67 ≥ 15%, n=33), luminal B2 (HR+/HER2+, n=83), HER2 with trastuzumab (HER2[T+]) (HR–/HER2+/use of trastuzumab, n=14), HER2 without trastuzumab (HER2[T–]) (HR–/HER2+, n=31), and triple negative (TN) (HR–/HER2–, n=61). Results After a median follow-up period of 7.2 years, 26 IBTRs and 37 LRRs occurred. The 5-year LRR-free survival rates were luminal A, 96.4%; B1, 93.9%; B2, 90.3%; HER2(T+), 92.9%; HER2(T–), 78.3%; and TN, 79.6%. The 5-year IBTR-free survival rates were luminal A, 97.2%; B1, 93.9%; B2, 92.8%; HER2(T+), 92.9%; HER2(T–), 89.1%; and TN, 84.6%. In multivariate analysis, HER2(T–) (IBTR: hazard ratio, 4.2; p=0.04 and LRR: hazard ratio, 7.6; p < 0.01) and TN subtypes (IBTR: hazard ratio, 6.9; p=0.01 and LRR: hazard ratio, 8.1; p < 0.01) were associated with higher IBTR and LRR rates. A pathologic complete response (pCR) was found to show correlation with better LRR and a tendency toward improved IBTR controls in TN patients (IBTR, p=0.07; LRR, p=0.03). Conclusion The TN and HER2(T–) subtypes predict higher rates of IBTR and LRR after NAC and BCT. A pCR is predictive of improved IBTR or LRR in TN subtype.

The fouling characteristics of dissolved organic matter (DOM) in the fresh water and seawater compartments of the reverse electrodialysis (RED) system were investigated under natural water conditions. The salinity gradient power generation was governed monovalent ions whereas multivalent ions strongly contributed to the fouling formation of the ion-exchange membranes (IEMs). The partial deposition of DOM within the membrane pores during its passage from the fresh water compartment to the seawater compartment facilitated the fouling formation of the IEMs. Despite of the similar DOC losses in fresh water (DOC loss = 20%) and seawater (DOC loss = 22%) through the RED system, the colour variations of the anion-exchange membranes (AEMs) and spacers in contact with fresh water were more noticeable than those in contact with seawater. These results indicate that the deposition of hydrophobic DOM components onto the AEM surfaces water may lead to the increases in the pressure drop of the fresh water compartment and the decreases in the power density of the RED system. Therefore, an appropriate pre-treatment strategy capable of mitigating membrane fouling by hydrophobic DOM components seemed to be indispensable to maintain constantly the performance of the RED system under natural water conditions.

Here we describe the development and testing of a hybrid system that combines microbial electrolysis and reverse electrodialysis (RED) to benefit energy production from seawater. A tubular, continuous-flow, microbial electrolysis cell (MEC) was used prior to RED to remove multivalent ions (Ca2+ and Mg2+) that are known to decrease RED power generation due to high electric membrane resistance. When a membrane electrode assembly was applied to reduce external resistance in the MEC, Ca2+ and Mg2+ were effectively removed with efficiencies of 84 ± 5% and 99 ± 5% (current density of 4.0 ± 0.2 A/m2), respectively, and H2 was simultaneously generated. A high H2 (purity > 99.5%) production rate (2.00 ± 0.09 m3/m3·d) at an applied voltage of 1.5 V, and maximum electrical energy efficiency (169 ± 4%) was accomplished at an applied voltage of 0.9 V and with an anode hydraulic retention time of 6 h. Effluent (47 mS/cm) from the MEC was fed to the RED stack as a high-concentration solution and the conductivity of treated seawater was lower than untreated seawater (53.7 mS/cm) due to Ca2+ and Mg2+ elimination from the seawater. Despite its lower conductivity, treated seawater produced higher power (0.29 W/m2, 26% increase) compared to untreated seawater due to the removal of Ca2+ and Mg2+. Therefore, the MEC is superior to other energy-consuming seawater pretreatment system as it produces energy during seawater pretreatment and successfully integrates with RED to enhance power generation.

This study reports the direct synthesis of MoS2 thin film on Al foil by chemical vapor deposition in a closed reactor. The electrochemical properties of the thin film were analyzed using reverse electrodialysis between salt water and fresh water. Microscopic and spectroscopic analyses revealed the porous and defective surface morphologies and layered crystalline structure of the MoS2 thin film. In cross-sectional TEM images, the MoS2 thin film was random and obliquely layered on the surface of Al foil native oxide. According to electrochemical tests, the maximum gross power density of MoS2/Al was approximately 34 W/m2, 54% higher than that of the as-received Al and 78% superior to the bulk MoS2 disk. The results confirmed that MoS2 was uniformly coated on the Al foil. MoS2/Al is a superior and inexpensive cathode for reverse electrodialysis, representing a new energy application of MoS2.

Molybdenum disulfide (MoS2) is considered to be promising two-dimensional material in potential applications because of its superior properties. Herein, our work suggests another important application as an inexpensive and highly active cathode material in reverse electrodialysis (RED). The MoS2 (8, 36, 76, 100 nm)/rutile-phase TiO2/Ti (MoS2/rpTiO2/Ti) heterostructures were successfully prepared with the randomly layered and oblique 1T/2H-MoS2 by one-step chemical vapor deposition of starting precursors in a closed reactor. The MoS2/rpTiO2/Ti reveals a thickness-dependent RED performance. Moreover, the MoS2 synthesis after sulfur modification of Ti surface (MoS2/smrpTiO2/Ti) increases the gross power density and reduces internal resistance of RED stack, indicating that the interfacial engineering between MoS2 and rpTiO2 improves both the catalytic activity and charge transfer efficiency. As a result, the highest gross power density of approximately 270 W/m2electrode was achieved using a RED stack mounted with 50-cell-pair of ion exchange membranes, which is comparable to that of platinum. Our work not only suggests that the MoS2/smrpTiO2/Ti heterostructure shows grate potential in RED stack, but also provides the importance of interface engineering between MoS2 and TiO2 through sulfate-bridge and sulfur-doping in MoS2-based electrocatalytic devices.

Reverse electrodialysis (RED) has vast potential as a clean, nonpolluting, and sustainable renewable energy source; however, pilot-scale RED studies employing real waters remain rare. This study reports the largest RED (1000 cell pairs, 250 m2) with municipal wastewater effluent (1.3–5.7 mS/cm) and seawater (52.9–53.8 mS/cm) as feed solutions. The RED stack was operated at a velocity of 1.5 cm/s and the pilot plant produced 95.8 W of power (0.38 W/m2 total membrane or 0.76 W/m2cell pair). During operation of the RED, the inlet design of the stack, comprising thin spacers, and the water dissociation reaction at the cathode were revealed as vulnerabilities of the stack. Specifically, pressure drops at the fluid inlet parts had the most detrimental effects on power output due to clogged spacers around the inlet parts. In addition, precipitates resulting in inorganic fouling were inevitable during the water dissociation reaction due to significant potential generated by the stack in the cathode chamber. Na+ and Cl− accounted for the majority of ions transferred from seawater to wastewater effluent through ion exchange membranes (IEMs). Moreover, some divalent cations in seawater, Mg2+ and Ca2+, were also transferred to the wastewater effluent. Some organics with relatively low molecular weights in the wastewater effluent passed through the IEMs, and their hydrophobic properties elevated the specific UV absorbance (SUVA) level in the seawater.

To analyze the causes and patterns of unexplained carcinoembryonic antigen (CEA) elevation after curative treatment in locally advanced rectal cancer patients. Among the 1309 locally advanced rectal cancer patients treated with curative resection and radiotherapy between January 2001 and June 2011, 325 patients who postoperatively developed abnormal CEA elevation were reviewed. The unexplained CEA elevation was defined as a CEA level higher than 5 ng/mL with no evidence of cancer recurrence at the time of elevation. Of the 325 patients, 143 (44%) had unexplained CEA elevations. The causes were categorized as delayed recurrence (n = 29, 20%), non-colorectal malignancy (n = 10, 7%), and non-malignancy-related conditions (n = 104, 73%). Shorter intervals between treatment and the first CEA elevation, and a higher peak CEA level, were observed in the delayed recurrence group compared with the non-colorectal malignancy or non-malignancy-related group (intervals of 6.8 vs. 44.9 vs. 23.2 months, respectively, p = 0.002; and peak CEA levels of 9.9 vs. 7.1 vs. 6.2 ng/mL, respectively, p = 0.034). In patients who showed delayed recurrence, the interval between the first CEA elevation and diagnosis of recurrence was a median of 13.0 months (range 3.8–60.6 months). Smoking was the most common cause for non-malignancy-related conditions. The patterns of unexplained CEA elevations were defined as sporadic (n = 78, 55%), stationary (n = 37, 26%), and increasing (n = 28, 20%). The patterns were significantly different depending on the cause (p

Energy and cost effective pretreatment of seawater is essential for any desalination plant to convert seawater into clean water successfully. This study shows a way to pretreat seawater without excessive input of electrical energy or high pressure; it uses a bioelectrochemical cell with two chambers, divided by an anion exchange membrane (AEM). When bacteria attached on the anode produce current using organic matter as a source of fuel, hydroxyl ions can be generated in the cathode chamber, which can increase the alkalinity of the catholyte (seawater); scale-forming ions such as Ca 2 + and Mg 2 + in seawater can be removed by forming precipitates in the cathode chamber. Our results show that 84% of Ca 2 + and 37% of Mg 2 + in seawater can be effectively removed while treating wastewater in the anode chamber. These results indicate a new method to pretreat seawater without external energy input since the cell accomplishes selective removal of divalent cations using an electrochemical cathode reaction. This study provides evidence that this new method can be a viable option for membrane based seawater pretreatment and desalination processes to significantly mitigate scale problems of membranes.

Background: Pelvic lymph node (LN) status after preoperative chemoradiotherapy (CRT) is an important indicator of oncologic outcome in patients with locally advanced rectal cancer. The purpose of this study was to develop a nomogram to predict LN status after preoperative CRT in locally advanced rectal cancer patients. Methods: The nomogram was developed in a training cohort (n=891) using logistic regression analyses and validated in a validation cohort (n=258) from a prospectively registered tumour registry at Asan Medical Center. The model was internally and externally validated for discrimination and calibration using bootstrap resampling. Model performance was evaluated by the concordance index (c-index) and calibration curve. Results: Pretreatment ypT stage, patient age, preCRT tumour differentiation, cN stage, lymphovascular invasion, and perineural invasion were reliable predictors of LN metastasis after preoperative CRT. The nomogram developed using these parameters had c-indices of 0.81 (training) and 0.77 (validation). The calibration plot suggested good agreement between actual and nomogram-predicted LN status after preoperative CRT. Conclusions: This nomogram improves prediction of LN status after preoperative CRT in patients with locally advanced rectal cancer. It will be useful for counselling patients as well as for the design and stratification of patients in clinical trials.

When operating reverse electrodialysis (RED) with several hundreds of cell pairs, a large stack voltage of more than 10 V facilitates water electrolysis, even when redox couples are employed for the electrode reaction. Upon feeding natural water containing multivalent ions, ion crossover through a shielding membrane causes inorganic scaling around the cathode and the interior of the membrane stack, due to the combination with the hydroxide ions produced via water reduction. In this work, we introduce a bipolar membrane (BPM) as a shielding membrane at the cathode to suppress inorganic precipitation. Water splitting in the bilayer structure of the BPM can block the ions diffusing from the catholyte and the feed solution, maintaining the current density. To evaluate the effect of the BPM on the inorganic precipitates, diluted sea salt solution is allowed to flow through the outermost feed channel near the cathode, in order to maintain as large a stack voltage as possible, which is important to induce water splitting in the BPM when incorporated into an RED stack of 100 cell pairs. We measure the electric power of the RED according to the arrangement of the BPM and compare it with that of conventional RED. The degree of inorganic scaling is also compared according to the kind of shielding membrane used (anion exchange membrane, cation exchange membrane, and BPM (Neosepta or Fumasep)). The BPM (Neosepta) shows the best performance for suppressing the formation of precipitates. It can hence be used to design a highly stable electrode system for long-term operation of a large-scale RED feeding natural water.

Aims and background We assessed the therapeutic efficacy of combined hypofractionated intensity-modulated radiotherapy with temozolomide in patients with primary glioblastoma. Methods and study design Thirty-nine patients with histologically confirmed glioblastoma were accrued. Using the simultaneous integrated boost technique, a dose of 50 Gy in 5-Gy fractions was applied to the gross tumor volume, together with 40 Gy in 4-Gy fractions and 30 Gy in 3-Gy fractions to the 1- and 2-cm margins from the gross tumor volume, respectively. Patients were also treated with concurrent temozolomide during intensity-modulated radiotherapy, followed by six cycles of adjuvant temozolomide. Results Median follow-up was 16.8 months (range, 4.3–54.3). Tumor progression was observed in 28 patients (71.8%), and the median time to progression was 6.8 months. Median survival was 16.8 months, and it was affected significantly by the extent of surgery. During adjuvant temozolomide treatment, 3 patients (9.7%) developed grade 3–4 hematologic or hepatic toxicity. Radiation necrosis developed in 7 patients (17.9%) and massive necrosis, requiring emergency surgery, in 1 patient (2.6%). Conclusions The regimen of hypofractionated intensity-modulated radiotherapy with temozolomide showed a relatively good outcome in patients with glioblastoma. Further studies are required to define the optimal fraction size for glioblastoma using this highly sophisticated radiation technique.

Plasma-catalytic hydrogenation of CO and CO 2 for producing methane was investigated with a catalyst-packed dielectric barrier discharge reactor. The characteristics of methane production from CO/H 2 or CO 2 /H 2 gas mixture were examined with bare alumina, TiO 2 /alumina, Ni/alumina, and Ni-TiO 2 /alumina under plasma and non-plasma conditions. The results obtained with bare alumina and TiO 2 /alumina suggest that either plasmainduced gas–phase reactions or photocatalytic reactions hardly contribute to the conversion of CO and CO 2 . The nonthermal plasma was found to have a promotive effect on the conversion of CO and CO 2 only when nickel-loaded catalysts such as Ni/alumina and Ni-TiO 2 /alumina were used, implying that the nonthermal plasma serves to promote the dissociation of carbon–oxygen bonds of CO and CO 2 adsorbed on the active sites of the catalysts, known as the slowest step of the reaction.

Carbon deposition via coke formation is one of the critical problems causing catalyst deactivation during the reforming of hydrocarbons. An effort was made to regenerate the catalyst (Ni/γ-alumina) by oxidation methods. Two approaches were carried out for the regeneration of the deactivated catalyst. The first one involves the plasma treatment of the deactivated catalyst in the presence of dry air over a temperature range of 300∼500 °C, while the second one only the thermal treatment in the same temperature range. The performance of the regenerated catalyst was evaluated in terms of C4H10 and CO2 conversions and the physicochemical characteristics were examined using a surface area analyzer, an elemental analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was observed that the carbon deposit (coke) on the catalyst was about 9.89 wt% after reforming C4H10 for 5 h at 540 °C. The simple thermal treatment at 400 °C reduced carbon content to 6.59 wt% whereas it was decreased to 3.25 wt% by the plasma and heat combination. The specific surface area was fully restored to the original state by the plasma-assisted regeneration at 500 °C. As far as the catalytic activity is concerned, the fresh and regenerated catalysts exhibited similar C4H10 and CO2 conversion efficiencies.

In order to define the role of adjuvant radiotherapy (RT), the clinical outcomes of patients with stage III/IV urothelial carcinoma of the upper urinary tract (UTUC) were reviewed.Clinical data from a total of 127 patients who underwent radical nephroureterectomy with bladder cuff were analyzed. While 36 patients underwent adjuvant RT following surgery, 91 were treated with surgery-alone. Differences in risk-adjusted treatment outcomes between the two groups were assessed using a multivariable Cox proportional-hazards model and inverse probability of treatment weighting with propensity score for balancing covariates including use of chemotherapy between the two groups was estimated.With a median follow-up of 38.3 months, 3-year actuarial locoregional recurrence-free survival rates were 89% vs. 61% in the RT vs. non-RT groups, respectively (p=0.01). Three-year bladder recurrence-free survival rates were 73% and 52% in favor of the RT group (p=0.02). After adjustment for differences in covariates, the risks of locoregional, bladder, and disease recurrence were found significantly lower in the RT group.Adjuvant RT may be beneficial in terms of locoregional and bladder control in patients with stage III/IV UTUC. Further prospective studied are needed to verify these findings.

PURPOSE To evaluate the prognostic value of preoperative neck lymph node (LN) assessment with (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET), computed tomography (CT), and magnetic resonance imaging (MRI) in oral cavity squamous cell carcinoma (OSCC) patients with pathologically positive LN. MATERIALS AND METHODS In total, 47 OSCC patients with pathologically positive LN were retrospectively reviewed with preoperative (18)F-FDG PET and CT/MRI. All patients underwent surgical resection, neck dissection and postoperative adjuvant radiotherapy and/or chemotherapy between March 2002 and October 2010. Histologic correlation was performed for findings of (18)F-FDG PET and CT/MRI. RESULTS Thirty-six (76.6%) of 47 cases were correctly diagnosed with neck LN metastasis by (18)F-FDG PET and 32 (68.1%) of 47 cases were correctly diagnosed by CT/MRI. Follow-up ranged from 20 to 114 months (median, 56 months). Clinically negative nodal status evaluated by (18)F-FDG PET or CT/MRI revealed a trend toward better clinical outcomes in terms of overall survival, disease-free survival, local recurrence-free survival, regional nodal recurrence-free survival, and distant metastasis-free survival rates even though the trends were not statistically significant. However, there was no impact of neck node standardized uptake value (SUV(max)) on clinical outcomes. Notably, SUV(max) showed significant correlation with tumor size in LN (p < 0.01, R(2) = 0.62). PET and CT/MRI status of LN also had significant correlation with the size of intranodal tumor deposit (p < 0.05, R(2) = 0.37 and p < 0.01, R(2) = 0.48, respectively). CONCLUSION (18)F-FDG PET and CT/MRI at the neck LNs might improve risk stratification in OSCC patients with pathologically positive neck LN in this study, even without significant prognostic value of SUV(max).

Purpose To evaluate the treatment outcome and prognostic factor after postoperative radiotherapy in retroperitoneal sarcoma. Materials and methods Forty patients were treated with surgical resection and postoperative radiotherapy for retroperitoneal sarcoma from August 1990 to August 2008. Treatment volume was judged by the location of initial tumor and surgical field, and 45-50 Gy of radiation was basically delivered and additional dose was considered to the high-risk area. Results The median follow-up period was 41.4 months (range, 3.9 to 140.6 months). The 5-year overall survival (OS) was 51.8% and disease free survival was 31.5%. The 5-year locoregional recurrence free survival was 61.9% and distant metastasis free survival was 50.6%. In univariate analysis, histologic type (p = 0.006) was the strongest prognostic factor for the OS and histologic grade (p = 0.044) or resection margin (p = 0.032) had also effect on the OS. Histologic type (p = 0.004) was unique significant prognostic factor for the actuarial local control. Conclusion Retroperitoneal sarcoma still remains as a poor prognostic disease despite the combined modality treatment including surgery and postoperative radiotherapy. Selective dose-escalation of radiotherapy or combination of effective chemotherapeutic agent must be considered to improve the treatment result especially for the histopathologic type showing poor prognosis.

INTRODUCTION:The locoregional recurrence (LRR) rate was reported as high as approximately 20% in stage I-II breast cancer following mastectomy. To investigate the risk factors for LRR in pT1-2N0-1 breast cancer patients treated with mastectomy but not radiation, and to define a subgroup of patients at high risk of LRR who may benefit from postmastectomy radiotherapy (PMRT). METHODS AND MATERIALS:In total, 390 patients with pT1-2N0M0 (n = 307) and pT1-2N1M0 (n = 83) breast cancer who underwent total mastectomy without adjuvant radiotherapy from 2002 to 2011 were enrolled in the study. RESULTS:After a median follow-up period of 5.6 years (range, 0.6-11.3 years), 21 patients had 18 systemic relapses and 12 LRRs including six in the chest wall and eight in the regional nodal area. The 5-year LRR-free survival (LRRFS) rates were 97.0% in pN0, 98.8% in pN1, and 97.4% in all patients. Multivariate analysis revealed that age < 50 years (Hazard Ratio, 11.4; p = 0.01) and no adjuvant chemotherapy (Hazard Ratio, 10.2; p = 0.04) were independent risk factors for LRR in pN0 patients. Using these factors, the 5-year LRRFS rates were 100% without any risk factors, 96.4% with one risk factor, and 86.7% with two risk factors. In pN1 patients, multivariate analysis revealed that having a hormone receptor negative tumor (Hazard Ratio, 18.3; p = 0.03) was the only independent risk factor for LRR. The 5-year LRRFS rates were 100.0% for luminal type, and 92.3% for non-luminal type cancer. CONCLUSION:Patients with pT1-2N0-1 breast cancer who underwent total mastectomy without PMRT could be stratified by nodal stage and risk factors for LRR. PMRT may have of value for node negative patients aged less than 50 years and who are not treated with adjuvant chemotherapy, and for non-luminal type patients with one to three positive nodes.

Materials and Methods: We evaluated 335 consecutive patients with clinical stage II-III breast cancer with known hormone receptor (HR), HER2, and Ki-67 who received NAC plus BCT from 2002 to 2009. Patients were classified into six molecular subtypes: luminal A (HR+/HER2-/Ki-67

513 Background: Pelvic lymph node status after preoperative chemoradiotherapy (CRT) is not only an important indicator for oncologic outcome but critical information to determine the type of a subsequent surgical resection (i.e. curative surgery or local excision) in patients with locally advanced rectal cancer. The purpose of this study is to develop a nomogram to predict the lymph node status after preoperative CRT in rectal cancer patients whose ypT information is available. Methods: Using logistic regression analyses, we constructed a prediction model to predict the probability of lymph node metastasis after preoperative CRT in a cohort of 1,099 patients with rectal cancer treated with preoperative CRT and total mesorectal excision (TME) from 2007 to 2011. The model was internally validated for discrimination and calibration using bootstrap resampling. Results: Pretreatment clinical nodal stage, distant metastasis, pre- and post-treatment tumor differentiation, and ypT stage were reliable predictors for lymph node metastasis after preoperative CRT. The nomogram developed using these parameters represents a valid and accurate method for predicting lymph node metastasis after preoperative CRT in rectal cancer patients. (c-index: 0.75) Patients with low pretreatment nodal stage, nonmetastatic, and well differentiated rectal adenocarcinoma downstaged to ypT0-1 after preoperative CRT will have low chance of pelvic lymph node involvement. Conclusions: Our model is expected to assist clinicians in quantifying the benefit of radical resection and finding out the patient group who can be treated with local excision after preoperative CRT for rectal cancer.