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Aim: To evaluate the efficacy and tolerability of an initial triple combination therapy (TCT) compared with conventional stepwise add‐on therapy (SAT) in patients with newly diagnosed type 2 diabetes (T2D). Materials and Methods: This multicentre, randomized, 104‐week, open‐label trial randomized 105 patients with drug‐naïve T2D (with HbA1c level ≥ 8.0%, < 11.0%) to the TCT (1000 mg of metformin, 10 mg of dapagliflozin and 5 mg of saxagliptin once daily) or SAT (initiated with metformin, followed by glimepiride and sitagliptin) groups. The primary outcome was the proportion of patients who achieved an HbA1c level of less than 6.5% without hypoglycaemia, weight gain of 5% or higher, or discontinuation of drugs because of adverse events at week 104. Results: HbA1c reduction from baseline at week 104 was similar between the groups (the least squares mean change was −2.56% in the TCT group vs. –2.75% in the SAT group). The primary outcome was achieved in 39.0% and 17.1% of the TCT and SAT groups, respectively, with a risk difference of 22.0 (95% confidence interval 3.0, 40.8; P =.027). HbA1c level less than 6.5% at week 104 was 46.3% in both the TCT and SAT groups, whereas the incidence of hypoglycaemia, weight gain, or discontinuation of drugs was 16.7% and 62.0% in the TCT and SAT groups, respectively (P <.001). TCT was well‐tolerated and had fewer adverse events than SAT. Conclusions: Among newly diagnosed patients with T2D, initial TCT effectively lowered HbA1c levels with higher tolerability and safety than SAT for 104 weeks, suggesting a novel strategy for initial combination therapy in T2D patients. [ABSTRACT FROM AUTHOR]

Transforming growth factor β (TGFβ) is present in blood of patients who do not respond to anti-programmed cell death (ligand) 1 [PD-(L)1] treatment, and through synergy with vascular endothelial growth factor (VEGF), it helps to create an environment that promotes tumor immune evasion and immune tolerance. Therefore, simultaneous inhibition of TGFβ/VEGF is more effective than targeting TGFβ alone. In this study, the dual inhibitory mechanism of TU2218 was identified through in vitro analysis mimicking the tumor microenvironment, and its antitumor effects were analyzed using mouse syngeneic tumor models. TU2218 directly restored the activity of damaged cytotoxic T lymphocytes (CTLs) and natural killer cells inhibited by TGFβ and suppressed the activity and viability of regulatory T cells. The inactivation of endothelial cells induced by VEGF stimulation was completely ameliorated by TU2218, an effect not observed with vactosertib, which inhibits only TGFβ signaling. The combination of TU2218 and anti-PD1 therapy had a significantly greater antitumor effect than either drug alone in the poorly immunogenic B16F10 syngeneic tumor model. The mechanism of tumor reduction was confirmed by flow cytometry, which showed upregulated VCAM-1 expression in vascular cells and increased influx of CD8 + CTLs into the tumor. As another strategy, combination of anti-CTLA4 therapy and TU2218 resulted in high complete regression (CR) rates in CT26 and WEHI-164 tumor models. In particular, immunological memory generated by the combination of anti-CTLA4 and TU2218 in the CT26 model prevented the development of tumors after additional tumor cell transplantation, suggesting that the TU2218-based combination has therapeutic potential in immunotherapy. [ABSTRACT FROM AUTHOR]

This paper proposes a novel phase-resolved partial discharge (PRPD) sensor embedded in a MV-class bushing for high-accuracy insulation analysis. The design, fabrication, and evaluation of a PRPD sensor embedded in a MV-class bushing aimed to achieve the detection of partial discharge (PD) pulses that are phase-synchronized with the applied primary HV signal. A prototype PRPD sensor was composed of a flexible printed circuit board (PCB) with dual-sensing electrodes, utilizing a capacitive voltage divider (CVD) for voltage measurement, the D-dot principle for PD detection, and a signal transducer with passive elements. A PD simulator was prepared to emulate typical PD defects, i.e., a metal protrusion. The voltage measurement precision of the prototype PRPD sensor was satisfied with the accuracy class of 0.2 specified in IEC 61869-11, as the maximum corrected voltage error ratios and corrected phase errors in 80%, 100%, and 120% of the rated voltage (13.2 kilovolts (kV)) were less than 0.2% and 10 min, respectively. In addition, the prototype PRPD sensor had good linearity and high sensitivity for PD detection compared with a conventional electrical detection method. According to performance evaluation tests, the prototype PRPD sensor embedded in the MV-class bushing can measure PRPD patterns phase-synchronized with the primary voltage without any additional synchronization equipment or system. Therefore, the prototype PRPD sensor holds potential as a substitute for conventional commercial PD sensors. Consequently, this advancement could lead to the enhancement of power system monitoring and maintenance, contributing to the digitalization and minimization of power apparatus. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is the primary opportunistic human pathogen responsible for a range of acute and chronic infections; it poses a significant threat to immunocompromised patients and is the leading cause of morbidity and mortality for nosocomial infections. Its high resistance to a diverse array of antimicrobial agents presents an urgent health concern. Among the mechanisms contributing to resistance in P. aeruginosa, the horizontal acquisition of antibiotic resistance genes (ARGs) via mobile genetic elements (MGEs) has gained recognition as a substantial concern in clinical settings, thus indicating that a comprehensive understanding of ARG dissemination within the species is strongly required for surveillance. Here, two approaches, including a systematic literature analysis and a genome database survey, were employed to gain insights into ARG dissemination. The genome database enabled scrutinizing of all the available sequence information and various attributes of P. aeruginosa isolates, thus providing an extensive understanding of ARG dissemination within the species. By integrating both approaches, with a primary focus on the genome database survey, mobile ARGs that were linked or correlated with MGEs, important sequence types (STs) carrying diverse ARGs, and MGEs responsible for ARG dissemination were identified as critical factors requiring strict surveillance. Although human isolates play a primary role in dissemination, the importance of animal and environmental isolates has also been suggested. In this study, 25 critical mobile ARGs, 45 critical STs, and associated MGEs involved in ARG dissemination within the species, are suggested as critical factors. Surveillance and management of these prioritized factors across the One Health sectors are essential to mitigate the emergence of multidrug-resistant (MDR) and extensively resistant (XDR) P. aeruginosa in clinical settings. [ABSTRACT FROM AUTHOR]

[Display omitted] The pseudocapacitive metal oxide anchored nanocarbon-based three-dimensional (3D) materials are considered attractive electrode materials for high-performance supercapacitor applications. However, the complex multistep synthesis approaches raise production costs and act as a major barrier to the practical real-world field. To overcome this limitation, in this study, an easily scalable and effective fabrication approach for the development of iron oxide (Fe 3 O 4) anchored highly porous carbon nanotube hybrid foam (f- Fe 3 O 4 /O-CNTF) with micro/mesoporous structure was suggested to improve the durability and energy storage performance. The surface morphology-tuned f -Fe 3 O 4 /O-CNTF (f -Fe 3 O 4 /O-CNTF(M)) was fabricated through electromagnetic interaction between the anchored magnetic Fe 3 O 4 on the CNT surface and the applied magnetic field. The obtained results clearly demonstrated that the changed surface morphology of the f -Fe 3 O 4 /O-CNTF(M) strongly affected the meso- and micropore structure, electrochemical performance, and durability. Consequently, the f -Fe 3 O 4 /O-CNTF(M) showed an almost 120% enhanced specific surface area and nearly 1.9 times increased specific capacitance compared to that of the f -Fe 3 O 4 /O-CNTF. Furthermore, the changed surface morphology successfully prevented the re-aggregation of the initial structure and significantly improved durability. As a result, f -Fe 3 O 4 /O-CNTF(M) showed outstanding cycling stability, maintaining almost 100% capacitance retention after 14,000 cycles. Consequently, the assembled symmetric supercapacitor device delivered an energy density of 20.1 Wh·kg−1 at a power density of 0.37 kW·kg−1 with good cycling stability. These results suggest that the f -Fe 3 O 4 /O-CNTF(M) can potentially be used as an electrode for supercapacitors with good durability. [ABSTRACT FROM AUTHOR]

In this study, we suggest a simple and effective one-pot hybrid reduction process for the mass production of high-quality reduced graphene oxide (rGO) by simultaneously doing deoxygenation and healing reactions. During the microwave-irradiated thermal reduction, intercalated benzene in the GO easily generates acetylene by pyrolysis; the released acetylene react with surrounding defect sites in the GO surface to successfully form new C–C bonds. As a result of the newly formed sp 2 -hybridized C–C bond in the rGO surface, the defect-repaired rGO (rGO-B) shows remarkably enhanced crystallinity (I D /I G ratio: rGO-B, 0.63; rGO-T, 1.08), thermal stability, and electrical properties over that of rGO prepared without a carbon-source supplement (rGO-T). Especially, compared to the rGO-T, the rGO-B had 4.4 times more carrier density and 18 times increased carrier mobility because of the restoration of defect sites in the rGO-B surface. The rGO-B exhibited six times higher electrical conductivity than did rGO-T because of the improved carrier mobility. These results obviously suggest that the reduction of GO by means of microwave-irradiated thermal reduction with a carbon-source supplement could be a powerful approach for commercial mass production of high-quality rGO because of its easy manufacturing approach. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Age-related changes in body composition include decreased muscle mass and preserved or increased fat mass. There is no anthropometric index to assess both muscle and fat mass. Methods Using a cross-sectional sample of 602 participants aged ≥65 years from the Ansan Geriatric study, we evaluated the association of weight-adjusted waist index (WWI) with muscle and fat mass and compared these with body mass index (BMI) and waist circumference (WC). WWI was calculated as WC (cm) divided by the square root of body weight (kg). Body composition was measured using bioelectrical impedance analysis, dual-energy X-ray absorptiometry and abdominal computed tomography. Results WWI positively correlated with total abdominal fat area (TFA) (r  = 0.421, P  < 0.001), visceral fat area (VFA) (r  = 0.264, P  < 0.001), and percentage of total tissue fat (r  = 0.465, P  < 0.001), but negatively correlated with appendicular skeletal muscle mass (ASM) (r  = −0.511, P  < 0.001) and ASM/height2 (r  = −0.324, P  < 0.001). Mean ASM was highest in the first quartile of WWI (17.85 kg/m2) and showed a decreasing trend, with the lowest value in the fourth WWI quartile (13.21 kg/m2, P for trend <0.001). In contrast, mean TFA was lowest in the first quartile and highest in the fourth WWI quartile (P for trend <0.001). The probability of combined low muscle mass and high fat mass was >3× higher in the fourth WWI quartile than in the lowest quartile (odds ratio 3.22, 95% confidence interval 1.32–7.83). Conclusions WWI is an anthropometric index positively associated with fat mass and negatively associated with muscle mass in older adults. [ABSTRACT FROM AUTHOR]

Summary: Panax ginseng C. A. Meyer, reputed as the king of medicinal herbs, has slow growth, long generation time, low seed production and complicated genome structure that hamper its study. Here, we unveil the genomic architecture of tetraploid P. ginseng by de novo genome assembly, representing 2.98 Gbp with 59 352 annotated genes. Resequencing data indicated that diploid Panax species diverged in association with global warming in Southern Asia, and two North American species evolved via two intercontinental migrations. Two whole genome duplications (WGD) occurred in the family Araliaceae (including Panax) after divergence with the Apiaceae, the more recent one contributing to the ability of P. ginseng to overwinter, enabling it to spread broadly through the Northern Hemisphere. Functional and evolutionary analyses suggest that production of pharmacologically important dammarane‐type ginsenosides originated in Panax and are produced largely in shoot tissues and transported to roots; that newly evolved P. ginseng fatty acid desaturases increase freezing tolerance; and that unprecedented retention of chlorophyll a/b binding protein genes enables efficient photosynthesis under low light. A genome‐scale metabolic network provides a holistic view of Panax ginsenoside biosynthesis. This study provides valuable resources for improving medicinal values of ginseng either through genomics‐assisted breeding or metabolic engineering. [ABSTRACT FROM AUTHOR]

The synthesis of metal oxide composites with porous structures for supercapacitor application has drawn much attention owing to their high surface area and easy access of the electrolyte ions to the electrode surface through the pores of the active materials. A facile hydrothermal approach is suggested for the synthesis of porous CuCo 2 O 4 composite sheets and their application as an active electrode material for supercapacitor application. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) measurements show the formation of porous CuCo 2 O 4 composite sheets. BET surface area measurements show that the porous CuCo 2 O 4 composite sheet has 69.44 m 2  g −1 surface area, which is 4.7 times higher than quasi-spherical CuCo 2 O 4 nanoparticles. The porous CuCo 2 O 4 composite sheet delivered 1037 C g −1 specific capacity at 5 mV s −1 . Additionally, the porous CuCo 2 O 4 composite sheet retained 94% of its initial specific capacity after 5000 charge-discharge cycles at 10 A g −1 indicating an excellent cyclic stability. This excellent supercapacitive performance is attributed to the high surface area and enhanced ion transport through the pores of the CuCo 2 O 4 sheets. This high specific capacity and excellent cyclic stability of the porous CuCo 2 O 4 composite sheets prove to be a promising candidate for supercapacitor application. [ABSTRACT FROM AUTHOR]

Shape tailoring of active materials could alter the performance of supercapacitors. Herein, we report the ethylenediaminetetraacetic acid (EDTA) assisted hydrothermal approach for the synthesis of single crystalline CuCo 2 O 4 octahedrons and their application in a supercapacitor. Morphology and BET surface area analysis demonstrates the formation of CuCo 2 O 4 octahedrons with a surface area of 61.97 m 2  g −1 . As an active material, the CuCo 2 O 4 octahedrons exhibited a high specific capacity of 989 C g -1  at 5 mV s −1 . In addition, a long-term cyclic stability with 87% of its initial specific capacity retention was achieved after 5000 cycles at 10 A g −1 . This outstanding performance could be ascribed to its unique octahedron morphology. The electrochemical results demonstrate that CuCo 2 O 4 with such a unique octahedron architecture could be a potential active material for the development of a high performance supercapacitor. [ABSTRACT FROM AUTHOR]

Synthesis of palladium (Pd) nanostructures with unique shapes is crucial due to their shape dependent electrochemical activity. In the current investigation, we demonstrate the electrochemical synthesis of rod-like Pd nanostructures with the assistance of nicotinamide adenine dinucleotide (NAD + ). As-synthesized Pd nanorods were used as electrocatalysts for electrochemical oxidation of methanol and the development of highly sensitive platform for hydrazine detection. Additive NAD + played an important role in the morphology tuning of Pd nanostructures. Results of morphological study demonstrated the growth of Pd nanorods with an average size of 150 nm. The as-synthesized Pd nanorods had excellent electrocatalytic activity toward oxidation of methanol in alkaline pH and hydrazine oxidation in neutral pH. These Pd nanorods catalyzed the electrooxidation of methanol at −0.17 V with much better tolerance, excellent stability, and oxidation of hydrazine at −0.075 V. The Pd nanorod-based sensing platform delivered a low detection limit of 5 nM, sensitivity of 0.78 ± 0.02 μA mM −1 cm −2 , and stable response toward hydrazine sensing without any interference from potential interferents such as Na + , K + , NO 2 − , BrO 3 − , or Pb 2+ ion. Their electrochemical performances were found to be highly dependent on the morphology of Pd nanostructures. [ABSTRACT FROM AUTHOR]

ABSTRACT Kim, N.-H.; Hwang, J.H., and Kim, D.H., 2018. Evaluation of Mixing and Stratification in an Estuary of Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 96–100. Coconut Creek (Florida), ISSN 0749-0208. In the estuary, flow structures depend on the relative contributions of the tidal current and the released freshwater, which determine the mixing and the stratification. To understand how artificially discharged freshwater affect the flow structure in an estuary of Korea, flow velocities, temperature, and salinity were measured in the field. During the field campaign, discharged freshwater cyclically forms the stratified layers during ebb tide and relatively well mixed water column during flood tide as in the conventional estuarine process. The gradient Richardson number evaluated such cyclic patterns quantitatively with the field measurement data, which were sampled following the tidal cycle and after the release of freshwater. In the early stage of the freshwater discharge, stratification dominates due to the large density difference, which overcomes the mixing by shear at the interface. As time goes on, the momentum of the released flow weakened and tidal modulation becomes significant and the discharged freshwater advected back and forth along the tidal currents. Different from the conventional mixing during flood, the stratification breaks down not by vertical mixing caused by the shear generated turbulence but by the vertical advection in the front of the gate. [ABSTRACT FROM AUTHOR]

Kim, N.-H.; Hwang, J.H., and Kim, D.H., 2018. Evaluation of Mixing and Stratification in an Estuary of Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 96–100. Coconut Creek (Florida), ISSN 0749-0208. In the estuary, flow structures depend on the relative contributions of the tidal current and the released freshwater, which determine the mixing and the stratification. To understand how artificially discharged freshwater affect the flow structure in an estuary of Korea, flow velocities, temperature, and salinity were measured in the field. During the field campaign, discharged freshwater cyclically forms the stratified layers during ebb tide and relatively well mixed water column during flood tide as in the conventional estuarine process. The gradient Richardson number evaluated such cyclic patterns quantitatively with the field measurement data, which were sampled following the tidal cycle and after the release of freshwater. In the early stage of the freshwater discharge, stratification dominates due to the large density difference, which overcomes the mixing by shear at the interface. As time goes on, the momentum of the released flow weakened and tidal modulation becomes significant and the discharged freshwater advected back and forth along the tidal currents. Different from the conventional mixing during flood, the stratification breaks down not by vertical mixing caused by the shear generated turbulence but by the vertical advection in the front of the gate. [ABSTRACT FROM AUTHOR]

The fabrication of an effective electrocatalyst for cathodic oxygen reduction reaction (ORR) is important to enhance the performance of fuel cell applications. Here, we prepared a novel hybrid material based on the combination of iron single atoms–small iron nanoparticles homogeneously distributed on the surface of nitrogen-doped graphene nanosheets (Fe SA -Fe NPs /NG). The achieved Fe SA –Fe NPs /NG material exhibited high catalytic ORR behaviors with high positive values of +0.94 V and +0.81 V for onset potential and half-wave potential, respectively, as well as the remarkable stability with 90% retention of initial current over an operation period of 15 000 s), superior to commercial Pt/C in 0.1 M KOH medium. In addition, the material favored a four-electron reaction pathway along with good methanol crossover tolerance towards ORR. The outstanding catalytic performance could be attributed to the formation of a unique microporous nanoarchitecture owning large specific surface area of 103.63 m2 g−1 and high conductivity, which create rich active sites and fast charge transfer ability, thus effectively accelerating the adsorption and catalyzation processes to convert oxygen reactant to product during ORR. These findings suggest a novel route for the synthesis of potential catalysts exhibiting excellent efficiency and cost effectiveness for fuel cell industries. [Display omitted] • The functional catalyst of Fe SA –Fe NPs /NG is rationally prepared via simple route. • The formation of Fe SA –Fe NPs /NG produces more active sites and high conductivity. • The catalyst requires a positive onset potential of +0.94 V for ORR in 0.1 M KOH. • The catalyst shows good stability superior to commercial Pt/C in alkaline media. [ABSTRACT FROM AUTHOR]

Aims/Introduction To assess the time to initiation of insulin therapy, and concurrently investigate both patient- and physician-related factors associated with delaying insulin therapy in Korean patients with type 2 diabetes uncontrolled by oral hypoglycemic agents (OHAs). Materials and Methods This prospective, observational disease registry study was carried out across 69 centers in Korea. Type 2 diabetes patients who had received two or more OHAs within the past 5 years, had a glycated hemoglobin ≥8% in the past 6 months and had not received insulin were included. Data recorded on data collection forms during a 12-month period were analyzed. Results Of 2168 patients enrolled, 1959 were evaluated and classified as the insulin-initiated or insulin-delayed group. Insulin was prescribed for just 20% of the patients during a 1-year follow-up period, and less than half (44.5%) of the patients who were taking two OHAs started insulin after 6 years. Patient-related factors for delay in insulin initiation included older age, shorter duration of diabetes and lower glycated hemoglobin. Physician-related factors included age (~50 to <60 years), sex (women) and number (<1000) of patients consulted per month. Patient refusal (33.6%) and physicians' concerns of patient non-compliance (26.5%) were the major physician-reported reasons for delaying insulin therapy. Inconvenience of insulin therapy (51.6%) and fear of injection (48.2%) were the major reasons for patient refusal. Conclusions Insulin initiation is delayed in patients with type 2 diabetes uncontrolled by two or more OHAs in Korea. Patient- and physician-related factors associated with this delay need to be addressed for better diabetes management. [ABSTRACT FROM AUTHOR]

Ocean observations, such as buoys and research stations, incur enormous installation and operation costs. Therefore, it is necessary to optimally arrange the observation sites at suitable positions. In this study, a strategy for additional buoy installation in a currently operated buoy-observation network was proposed using the multi-objective optimization technique. The numerical simulation results of the Korea Operational Oceanographic System were used as input data. The surface current, water temperature, and salinity, which are parameters observed at buoys, were set as the design variables. The objective function was constructed by assigning weights to each design variable, and the optimal array was determined using a brute-force optimizer. The optimal solution is estimated in the form of Pareto-optimal solutions that can achieve optimal efficiency. Pareto-optimal solutions can produce candidates for optimal arrays, depending on which design variables are weighted. Each candidate array can effectively reproduce the local characteristics of the design variables, such as the speed and direction of the surface current and cold/hot bias of water temperature and salinity, which could not be obtained from the existing observation network. Such candidate arrays can provide multiple options according to the designer's intent in the decision-making process. • Proposed a strategy to install additional buoy-observation sites in existing network. • Observable ocean variables were considered using multi-objective optimization. • Weighted sum method combined objective functions and assigned weights to variables. • The brute-force optimizer determined the most optimal design site combinations. • The design variables were assigned weights based on the Pareto-optimal solutions. [ABSTRACT FROM AUTHOR]

In this work, catalytic Rh 2 O 3 -functionalized WO 3 nanofibers (NFs) were synthesized via an electrospinning route and used as a highly selective acetone-sensing layer for potential diagnosis of diabetes. Catalytic rhodium nanoparticles (Rh NPs) with average diameters of 5.0 ± 0.52 nm, which were synthesized by the polyol process, were dispersed in water with W precursor and poly(vinylpyrrolidone) (PVP) for electrospinning. As-spun Rh NP-loaded W precursor/PVP composite NFs were calcined at 600 °C for 1 h in air atmosphere to achieve Rh 2 O 3 -decorated WO 3 NFs. Microstructure evolution and chemical composition of Rh 2 O 3 -decorated WO 3 NFs as a function of Rh-loading amounts, i.e., 0.01 wt%, 0.05 wt%, 0.10 wt%, and 0.15 wt%, were examined using energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). The mean size (30 nm) of the WO 3 crystallites in Rh 2 O 3 -decorated WO 3 NFs was much smaller than that (60 nm) of the WO 3 crystallites in pristine WO 3 NFs. The Rh 2 O 3 -decorated WO 3 NFs showed outstanding acetone (CH 3 COCH 3 ) sensing response ( R air / R gas = 41.2 to 5 ppm), which was 4.6 times higher than the response ( R air / R gas = 9.0 to 5 ppm) of pristine WO 3 NFs at highly humid atmosphere (95% RH). In addition, superior acetone cross-sensitivity of the Rh 2 O 3 -decorated WO 3 NFs was observed in other interfering gases such as pentane ( n -C 5 H 12 ), ammonia (NH 3 ), toluene (C 6 H 5 CH 3 ), carbon monoxide (CO), and ethanol (C 2 H 5 OH) at 5 ppm. These results are highly promising for the accurate and selective detection of acetone in exhaled breath for potential diagnosis of diabetes. [ABSTRACT FROM AUTHOR]

Nam-Hoon Kim; Jin Hwan Hwang, and Hyeyun Ku, 2016. Stratification of tidal influenced navigation channel. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 63-67. Coconut Creek (Florida), ISSN 0749-0208. Field observation was performed to understand the mixing and stratifying processes in an estuarine navigation channel. An artificial gate located at the mouth of Geum River in Korea discharges freshwater to the coastal sea. While the stratification in this channel is artificially controlled by gate operation, the mixing is determined by tide with about 6 m amplitude of semidiurnal constituent. Discharged freshwater mostly flows though the southern navigation channel and leads to the strong stratification, which could be due to the strong advection in the upper layer during the ebb. At the interface between buoyant current and bottom saltier water, the features of internal waves were observed also with the reduced gravity of 15-22 kg/m3. The gradient Richardson numbers show the seasonal variations of the stratification as expected. Relatively water column was pretty stably stratified in March and partially or well mixed in April and August throughout the regions of navigation channel. [ABSTRACT FROM AUTHOR]

Background: The association between body mass index (BMI) and mortality is not conclusive, especially in East Asian populations. Furthermore, the association has been neither supported by recent data, nor assessed after controlling for weight changes. Methods: We evaluated the relationship between BMI and all-cause or cause-specific mortality, using prospective cohort data by the National Health Insurance Service in Korea, which consisted of more than one million subjects. A total of 153,484 Korean adults over 30 years of age without pre-existing cardiovascular disease or cancer at baseline were followed-up until 2010 (mean follow-up period = 7.91 ± 0.59 years). Study subjects repeatedly measured body weight 3.99 times, on average. Results: During follow-up, 3,937 total deaths occurred; 557 deaths from cardiovascular disease, and 1,224 from cancer. In multiple-adjusted analyses, U-shaped associations were found between BMI and mortality from any cause, cardiovascular disease, and cancer after adjustment for age, sex, smoking status, alcohol consumption, physical activity, socioeconomic status, and weight change. Subjects with a BMI < 23 kg/m2 and ≥ 30 kg/m2 had higher risks of all-cause and cause-specific mortality compared with the reference group (BMI 23–24.9 kg/m2). The lowest risk of all-cause mortality was observed in subjects with a BMI of 25–26.4 kg/m2 (adjusted hazard ratio [HR] 0.86; 95% CI 0.77 to 0.97). In subgroup analyses, including the elderly and those with chronic diseases (diabetes mellitus, hypertension, and chronic kidney disease), subjects with a BMI of 25–29.9 kg/m2 (moderate obesity) had a lower risk of mortality compared with the reference. However, this association has been attenuated in younger individuals, in those with higher socioeconomic status, and those without chronic diseases. Conclusion: Moderate obesity was associated more strongly with a lower risk of mortality than with normal, underweight, and overweight groups in the general population of South Korea. This obesity paradox was prominent in not only the elderly but also individuals with chronic disease. [ABSTRACT FROM AUTHOR]

P-type Cu-Se thin films were deposited on glass substrates at room temperature using radio frequency magnetron sputtering by a single multi-component CuSe2 target. When using a multi-component target, the impact of the sputtering power on the homogeneity and stoichiometry within the thin films should be investigated in the depth direction to demonstrate a secondary effect on the electrical and optical properties of the thin films. Systematic characterization of the Cu-Se thin films, including the morphology, microstructure, chemical composition, and depth-directional chemical bonding state and defect structure of the thin films, revealed that the sputtering power played an important role in the homogeneity and stoichiometry of the thin films. At very low and very high sputtering power levels, the Cu-Se thin films exhibited more deviations from stoichiometry, while an optimized sputtering power resulted in more homogenous thin films with improved stoichiometry across the entire thin film thickness in the X-ray photoelectron spectroscopy depth profile, despite showing Se deficiency at all depths. A rapid decrease in carrier concentration, indicating a reduction in the net effect of total defects, was obtained at the optimized sputtering power with less deviation from stoichiometry in the Cu-Se thin films and the closest stoichiometric ratio at an intermediate depth. [ABSTRACT FROM AUTHOR]

A reduced graphene oxide (RGO)-NiFe 2 O 4 nanocomposite was synthesized by a simple one step hydrothermal approach and its application in the electrocatalytic oxidation of hydrazine was demonstrated. The as-synthesized nanocomposite was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, UV–visible spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Thermogravimetric analysis, Field emission-scanning electron microscopy (FE-SEM), and Transmission electron microscopy (TEM). The FE-SEM and TEM image analyses revealed that the NiFe 2 O 4 nanoparticles were uniformly distributed on the RGO sheets with a diameter and length of ∼10 and ∼100 nm, respectively. The XPS analysis confirmed the ionic states of Ni and Fe to be Ni 3+ and Ni 2+ , and Fe 2+ and Fe 3+ , respectively. Further, the electrochemical activity of the RGO-NiFe 2 O 4 nanocomposite was investigated by studying the oxidation of hydrazine. The RGO-NiFe 2 O 4 modified glassy carbon electrode (GCE) showed an outstanding electrocatalytic activity towards the oxidation of hydrazine as compared to the NiFe 2 O 4 and RGO modified electrodes. The enhanced electrocatalytic activity is due to the synergistic effect between RGO and NiFe 2 O 4 . Using amperometry, the lowest detection limit of 200 nM was achieved with the RGO-NiFe 2 O 4 modified GCE. Therefore, the RGO-NiFe 2 O 4 modified GCE can be used for the electrochemical oxidation of hydrazine. [ABSTRACT FROM AUTHOR]

Simple Summary: Inactivated foot-and-mouth disease (FMD) vaccines are used to protect livestock against the FMD virus. However, adequate levels of antibodies to provide protection against the FMD virus cannot be rapidly produced and take a long time to develop. In this study, to solve the challenge presented by the low antibody formation following FMD vaccination in pigs, an ionic amino–zinc complex (Amino–Zn), which has high bioavailability and immunity-enhancing effects, was administered orally. The effect on the FMD vaccine structural protein (SP) antibody formation was evaluated. As a result, the FMD vaccine SP antibody titer and immune indicators (IFN-γ, IgA) were significantly higher in the FMD vaccine group administered with 0.2% Amino–Zn in the feed compared with the positive control group (FMD vaccine only) after the first and second vaccinations. These results demonstrated that administering Amino–Zn effectively improved the antibody titer induced by the FMD vaccine and the immunity of the piglets. Foot-and-mouth disease (FMD) is a highly contagious animal disease that occurs in cloven-hoofed animals including pigs. To prevent FMD, vaccines and adjuvants are routinely used to induce an immune response; however, it requires an extended period of time to produce sufficient antibodies to prevent viral infection. In this study, we evaluated the increased effectiveness of the FMD vaccine structural protein (SP) antibody by administrating the Amino–Zn adjuvant to 100 pigs from 3 test pig farms in their feed. The FMD vaccine antibody titer and immunological index were analyzed using an enzyme-linked immunosorbent assay (ELISA) kit, and the hematological and blood biochemical parameters were analyzed using an automatic blood analyzer. The titer of the FMD vaccine SP antibodies in the 0.2% Amino–Zn-administered group was significantly increased compared to that of the positive control group only injected with FMD vaccine at 4 weeks after the first vaccination and at 4, 8, and 16 weeks after the second vaccination (p < 0.05). The FMD vaccine SP antibody positive rate was 100% until shipment. The IFN-γ and IgA levels were significantly increased by Amino–Zn administration 4 weeks after the first vaccination and 4 weeks after the second vaccination (p < 0.05). On the other hand, serum AST, and CPK (p < 0.001) were significantly decreased by Amino–Zn administration. These results show that the administration of Amino–Zn is effective in enhancing the antibody titer and immunogenicity of the FMD vaccine and can be used as an oral adjuvant (OrAd) to prevent viral diseases, such as FMD. [ABSTRACT FROM AUTHOR]

Abstract: Nafion–sulfonated polyether ether ketone (SPEEK)–graphene oxide (GO) nanocomposite membranes were prepared. The effects of the degree of oxidation of GO on the physical properties of the nanocomposites have been investigated using two varieties of GOs with low degree (GO) and high degree (HGO) of oxidation. The concentrations of the oxygen functionality in GO and HGO are 28.4% and 31.8%, respectively as calculated by XPS analysis, but the size of HGO is less than that of GO. Thermal stabilities of the composites are similar except for minor differences in weight loss of various composites due to the presence of different amounts of –SO3H and oxygen functionalities. The storage modulus of the HGO-based composite is the highest among the composites and the addition of SPEEK is detrimental to the mechanical properties in all cases. Optimum proton conductivity of 322.2mScm−1 is noted with Nafion containing 1wt% SPEEK and 0.75wt% HGO at 100% relative humidity (RH) and 90°C compared to 198mScm−1 under similar conditions. The maximum power density of 621.2mWcm−2 has been noted for the same composite membrane at 80°C and 100% RH. [Copyright &y& Elsevier]

Background & Aims The course of NAFLD (nonalcoholic fatty liver disease) and associated factors in nonobese subjects are not well established. We investigated contributing factors for the development and regression of NAFLD in nonobese Koreans, and whether they would differ from those of obese subjects. Methods Two thousand three hundred and seven adults aged over 18 years participated in this longitudinal observational study. The mean duration of follow-up was 28.7 (±13.2) months. The participants were divided into two groups according to the baseline BMI (nonobese group: BMI <25 kg/m2, obese group: BMI ≥25 kg/m2). The presence or absence of NAFLD was assessed by abdominal ultrasonography. Results Body weight change was independently associated with both the development and regression of NAFLD in nonobese subjects as well as obese subjects. Among the subjects who developed NAFLD, the amount of weight change was higher in nonobese subjects compared to obese subjects (1.6 ± 3.9% vs 0.6 ± 4.2%, P = 0.022); and among those who showed regression of NAFLD, the amount of weight change was lower in nonobese subjects (−1.9 ± 4.0% vs −5.0 ± 4.6%, P < 0.001). Among all the components of metabolic syndrome, only high triglyceride levels (>150 mg/ dl) at the baseline were significantly associated with both the development and regression of NAFLD in nonobese subjects (ORs, 1.54 (1.10-2.14), and 0.60 (0.38-0.96) respectively). Conclusion Body weight change and baseline triglyceride levels were strong indicators for the development and regression of NAFLD in a nonobese population. [ABSTRACT FROM AUTHOR]

In this work, we report a remarkably improved toluene response and superior cross-sensitivity against H2S molecules by combining Pd catalysts and highly porous WO3 nanofibers (NFs). We functionalized Pd catalysts inside and/or outside of WO3 NFs synthesized by electrospinning, which is a facile and versatile process for producing webs of metal oxide NFs. Pd-embedded WO3 NFs were obtained by the electrospinning of a Pd and W composite precursor/poly(methyl methacrylate) (PMMA) solution followed by calcination at 700°C. Pd nanoparticles (NPs) (6–10nm) synthesized by a polyol method were decorated on the WO3 NFs (Pd-NPs/WO3 NFs) by the attachment of the Pd NPs on as-prepared WO3 NFs. The gas sensing characteristics of pure WO3, Pd-embedded WO3, Pd-NPs/WO3, and Pd-NPs/Pd-embedded WO3 NFs were tested using H2S and toluene gases in a highly humid atmosphere (RH 90%), which is similar to human exhaled breath. The results showed that the Pd-NPs/Pd-embedded WO3 NFs whose inner and outer layers were decorated by Pd catalysts, exhibited a high toluene response (R air/R gas =5.5 at 1ppm) and remarkable selectivity against H2S (R air/R gas =1.36 at 1ppm) at 350°C, whereas pristine WO3 NFs showed superior H2S response (R air/R gas =11.1 at 1ppm) along with a negligible response toward toluene (R air/R gas =1.27 at 1ppm). The highly porous WO3 NFs decorated with Pd catalysts, exhibited potential feasibility, i.e., a low limit of detection (LOD) of 20ppb (R air/R gas =1.32) at 350°C, for application in VOCs sensors, particularly for diagnoses of lung cancer. [ABSTRACT FROM AUTHOR]

This work involves the comparative study of the effect of pore diameter and size of the unmodified and ionic liquid (IL)-functionalized mesoporous silica on the proton conductivity of phosphoric acid (PA)-doped poly(2,5-benzimidazole) (ABPBI) membranes. Two varieties of silica have been selected for this purpose: MCM-41 (UMC, pore diameters of 3.40nm and size 90–150nm) and SBA-15 (USB, pore diameters of 9.60nm and size 800–1100nm). The high degree of dispersion of silica particles in ABPBI matrix improved the storage modulus of the membrane comprising 5wt% IL-functionalized USB (dA5SIL) by 213% compared to that of the PA-doped ABPBI membrane at 250°C. The PA doping amounts of the USB-based composites are lower than those of the UMC-based composites, in spite of the larger pore diameter of USB. This is possibly due to the surface tension of PA, the larger size of USB compared to UMC and the inferior dispersion of USB in the ABPBI matrix. A maximum proton conductivity of 6.74 × 10–2 S cm–1 (e.g., 0.0674 S cm–1) has been obtained for the PA-doped composite membrane comprising 5wt% functionalized UMC (dA5MIL) at 150°C, which is similar to the room-temperature conductivity of Nafion at 100% RH. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen gas barrier properties of polymeric materials are a critical determinant of their practical use in hydrogen gas storage and transportation container applications. We fabricated multi-layered films containing poly(diallyldimethylammonium) chloride (PDDA) and sulfonated polyvinylidene fluoride (SPVDF)-graphene oxide (GO) composites through layer-by-layer (LBL) assembly to enhance the hydrogen gas barrier properties. Polyethylene terephthalate (PET) substrate was rendered hydrophilic by treatment with aqueous sodium hydroxide solution prior to LBL assembly construction. Positively-charged PDDA and negatively-charged SPVDF or SPVDF/GO composites were assembled by spin-coating and were tightly packed by electrostatic attraction. LBL assemblies were characterized by Fourier transform infrared (FT-IR) spectroscopy and Field emission scanning electron microscopy (FE-SEM) analyses. Electrostatic LBL assembled PDDA/SPVDF-GO films showed improved mechanical and gas barrier properties compared to their respective PDDA/SPVDF LBL assemblies without GO. The hydrogen gas transmission rate (GTR) of a 16 bi-layer LBL assembly with 2wt.% GO was 11.7cc/m2 datm, which was much lower than that of PET substrate (329.1cc/m2 datm) and a one bi-layer LBL assembly without GO (277.9cc/m2 datm). The drastic decrease in GTR indicates that LBL assembled films are suitable for use in high hydrogen barrier applications. [Copyright &y& Elsevier]

In this study, the composition of lead-free piezoelectric ceramics (1 − x)(Bi0.5Na0.5)TiO3–x(Ba0.5Sr0.5)TiO3 with excellent piezoelectric properties was investigated. Crystal analysis and electrical and piezoelectric properties were analyzed according to the content of the BST composition. A phase change from rhombohedral to tetragonal structure was observed in 0.12 BST, and the densest and most uniform microstructure was confirmed in this composition. The dielectric constant increased from 905 to 1692 as the composition of BST increased to 0.12 BST. Afterward, as the composition of BST increased, the permittivity tended to decrease. Additionally, at 0.12 BST, Pr was the highest at 23.34 μC/cm2. The piezoelectric charge constant (d33) and the electromechanical coupling coefficient (kp) were 152 pC/N and 0.37, respectively, and showed the highest values at 0.12 BST. Curie temperature (Tm) was analyzed 242 °C at 0.12 BST, the optimal composition. It was confirmed that the characteristics of 0.12 BST were excellent in all conditions. Therefore, it was confirmed that 0.12 BST is the optimal composition for (1 − x)BNT–xBST piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to investigate the effects of hybrid carbon fillers on the physical properties of polymer composites for bipolar plates of fuel cells. Hybrid carbon-filled poly(phenylene sulfide) (PPS) composites have been prepared via compression molding with graphite as main filler and different shaped supplementary filler such as carbon black, carbon fiber and multi-walled carbon nanotubes. Different types of conducting fillers, such as fibrous and particulate fillers, or different sizes of fillers show synergistic effects on the flexural strengths and electrical conductivities of the PPS based composites. Materials selection windows of hybrid fillers for desired flexural strength and electrical conductivity obtained by simple linear interpolation of the measured values provide useful tools for the development of PPS based composites for bipolar plate application. [Copyright &y& Elsevier]

Abstract: We investigated an electrochemical reaction on the cathode surface of an overcharged Li[Ni0.45Co0.18Mn0.25Al0.12]O2/Li system at the molecular level by using Raman, X-ray absorption spectroscopy (XAS), and 2D hetero-spectral correlation analyses. Changes in the Raman spectra during the overcharging process showed that variations in the local atomic environment occurred with increasing extraction of Li+ ions. XAS spectra obtained during the overcharging process showed that oxidized transition metals coexisted with inoxidizable transition metals. Additionally, synchronous 2D hetero-spectral Raman/XAS correlation spectra clearly elucidated the correlation between the Raman and XAS bands, confirming their band assignments. [Copyright &y& Elsevier]

Abstract: Cadmium sulfide (CdS) is one of the most widely used materials as a window layer in heterojunction thin film solar cells. Sputtering method for the preparation of CdS thin film was employed for the mass-production of large-area deposited CdS thin films. The electrical and optical properties of sputter-deposited CdS thin films varied with the annealing temperature, which were caused by changes in phase composition, grain size, and stoichiometry of CdS thin films. The improved optical transmittance of 72.25% (at average thickness of 843.93nm) and the optical band gap energy of 2.43eV were obtained at the optimum annealing temperature of 400°C. The resistivity below 103-order Ω cm and carrier concentration above 1016 carriers/cm3 are suitable for the requirements of window layers at this optimum annealing temperature. [Copyright &y& Elsevier]

Objectives To examine the relationship between depression and various components of body composition, including fat and muscle, in elderly Koreans. Design A cross-sectional sample of a longitudinal cohort from the Ansan Geriatric ( AGE) Study. Setting Elderly people living in urban area (Ansan City, South Korea). Participants Eight hundred thirty-six participants (378 male, 458 female) aged 60 and older were recruited from April 2006 to January 2008. Measurements Depressive symptoms were examined using the Korean version of the 30-item Geriatric Depression Scale ( KGDS). Participants taking antidepressant medications or with a KGDS score of 14 or greater were classified as having depression. Abdominal visceral fat area ( VFA) and subcutaneous fat area were assessed using single-slice computed tomography, and appendicular skeletal muscle mass ( ASM) and percentage body fat (% BF) were determined using whole-body dual-energy X-ray absorptiometry. Results Elderly men with depression had a lower ASM than those without depression ( P = .01) after adjusting for age, body weight, and height. In men, the risk of depression was lower with higher body mass index ( BMI) (odds ratio ( OR) per 1-standard deviation ( SD) increase = 0.70, 95% confidence interval ( CI) = 0.51-0.96) after adjusting for all confounding variables and higher ASM ( OR per 1- SD increase = 0.49; 95% CI = 0.29-0.85) after controlling for age, height, and weight. Similarly, depression was negatively associated with BMI in women ( OR per 1- SD increase = 0.73; 95% CI = 0.56-0.95). Waist circumference, % BF, and VFA were not consistently associated with depression in men or women. Conclusion Depression in elderly Koreans is associated with low body mass and sarcopenia, especially in men. [ABSTRACT FROM AUTHOR]

Abstract: A hybrid carbon system of graphite powder (GP) and continuous carbon fibre fabric (CFF) is used for an epoxy composite to improve the electrical conductivity, mechanical properties and mouldability of a composite bipolar plate. These improvements are achieved simultaneously by inserting several layers of CFF into the GP/epoxy composite to enhance the mechanical properties and in-plane conductivity. The electrical properties, flexural strength and mouldability of the composite plates are measured as a function of conducting filler content and number of CFF layers. The composites show improved electrical conductivity, flexural properties and mouldability. Composites with 70–75vol.% carbon fillers have the highest electrical conductivity with reasonable flexural properties. These results suggest that the poor mouldability and low through-plane electrical conductivity of the continuous fibre composite bipolar plate, as well as the weak flexural properties of GP composites, can be overcome by incorporating a GP/CFF hybrid system. [Copyright &y& Elsevier]

Abstract: It is well known that, theoretically, thin-film cadmium telluride (CdTe) solar cell technology can improve on the conversion efficiency and production costs of conventional silicon solar cell technology. Due to the optimal band gap energy (about 1.4eV) for solar energy absorption, high light absorption capability and lower cost requirements for solar cell production, CdTe has been widely researched as being suitable for commercial cell production. In this study, the sputtering method, which can improve on the cost-efficiency and mass-production of solar cells, was employed to deposit the CdTe thin film with various processing conditions such as sputtering power, and gas pressure. The effects of the processing conditions on the thickness-uniformity and surface morphology of the CdTe thin films were investigated using atomic force microscope (AFM) and ellipsometry for large-area solar cells. The photovoltaic properties of CdTe thin films were analyzed in relation to the different thickness-uniformity and surface morphology caused by the various process conditions. The thickness-uniformity, which was controlled by the process conditions in the sputtering process, was found to affect the photovoltaic properties of the sputtering-deposited CdTe thin films. Higher carrier concentration and better optical absorbance were obtained in CdTe thin films with a good thickness-uniformity. [Copyright &y& Elsevier]

Abstract: The passivating layer (also called the solid electrolyte interface, SEI) plays a key role in the performances of Li-ion batteries. In this work, we studied the surface reactions of Li[Ni0.31Co0.32Mn0.28Al0.09]O2 with the organic electrolyte in the overcharge state by means of FTIR, XPS, XAS, and 2D correlation analysis. The FTIR and XPS results revealed that several types of compounds are formed on the cathode surface. These results also suggest that the organic solvents are decomposed to a greater extent than the Li-salt during the overcharge state. Based on the 2D correlation analysis, we can deduce the following sequence of events: 287.0 (due to C−O)→290.0 (due to carbonate)→288.5 (due to C sp="0.25" />→291.5 (due to C−F x )→284.5eV (due to C:glyph name="sbnd" />H). [Copyright &y& Elsevier]

Abstract: In this study, we demonstrated the surface reaction in a LiCoO2/Li cell under high voltage condition and characterization of the composition and properties of electrode–electrolyte interface by 2D correlation analysis. 2D Raman correlation spectra revealed that the extraction of Li+ leads to the formation of surface components including Li2O and Co3O4 and structural distortion in hexagonal LiCoO2 structure. [Copyright &y& Elsevier]

Abstract: Hyperbranched poly(benzimidazole-co-benzene) (PBIB) with a honeycomb structure is synthesized by condensation polymerization of trimesic acid (TMA) and 3,3′-diaminobenzidine (DAB) for use as a membrane high-temperature proton-exchange membrane fuel cells (HT-PEMFCs). The hyperbranched honeycomb structure of polybenzimidazole (PBI) has been introduced to impart higher mechanical strength to doped PBI membranes. The stress at break of the phosphoric acid doped PBIB (DPBIB) membrane (29±3MPa) is comparable with that of Nafion (28±2MPa) and much superior to doped PBI membranes. The DPBIB membrane exhibits lower proton conductivity than Nafion 115. On the other hand, the proton conductivity of Nafion 115 is enhanced with increase in relative humidity, whereas humidity has only a moderate effect on the proton conductivity of the DPBIB membrane. Consequently, the Nafion 115 membrane in a fuel cell cannot operate in the absence of humidity, whereas the DPBIB membrane can perform well. The power output of the DPBIB membrane in a fuel cell is superior under humid conditions than under dry conditions. The maximum power output from the DPBIB and Nafion 115 membranes is comparable under humid conditions. It is concluded that the DPBIB membrane, but not Nafion, is suitable for application in HT-PEMFCs. [Copyright &y& Elsevier]

Abstract: Muti-walled carbon nanotubes (MWCNTs) were treated with different concentrations of potassium persulfate (KPS; K2S2O8) to improve their dispersion stability, which were characterized by thermal gravimetric analysis, ultraviolet/visible spectroscopy, field emission scanning electron microscopy and field emission transmission electron microscopy. The amount of sulfate groups on the MWCNTs increased with increasing KPS concentration, which enhanced the hydrophilicity, but deteriorated the dispersion stability. The optimal KPS concentration for the best dispersion stability of the KPS-treated MWCNTs was 0.01M. [Copyright &y& Elsevier]

Abstract: Poly(5-aminoisophthalic acid) (PAIPA) has been synthesized by the oxidative polymerization of 5-aminoisophthalic acid (AIPA), which is subsequently subjected to condensation polymerization with 3,3′-diaminobenzidine (DAB) to obtain poly(benzimidazole-co-aniline) (PBIANI), a self-cross-linked, net-structured, proton conducting polybenzimidazole (PBI) type of polymer membrane for the high temperature proton exchange membrane fuel cells (HT-PEMFC). The aniline monomer has been inserted judicially as an extra basic unit as well as a cross-linker between the benzimidazole units in order to ameliorate the proton conductivity and mechanical strength of PBI type membranes, simultaneously. The stress at break of the 45wt.% phosphoric acid doped PBIANI (DPBIANI) membrane is 26±3MPa. The proton conductivity of the DPBIANI membrane is 167mScm−1 at 120°C and at 100% RH. The effect of humidity on the proton conductivity of DPBIANI membrane is marginal. The DPBIANI membrane can perform without humidity in a fuel cell. However, the voltage and power output of the DPBIANI membrane in the fuel cell is superior under humid conditions compared to dry conditions. Overall, the DPBIANI membrane is suitable for HT-PEMFC with improved mechanical strength and enhanced proton conductivity. [Copyright &y& Elsevier]

Abstract: The effects of a surface treatment of carbon nanotubes (CNTs) on the electrical conductivity and the hydrophilicity of a polyaniline (PAni) coated CNTs (PAni-CNTs)/epoxy (EP) composites were examined. The surface of the CNTs was treated with various chemicals, such as acid mixtures (HNO3:H2SO4), potassium persulfate (KPS) and sodium dodecyl sulfate (SDS), to improve their dispersion and reactivity with PAni. The electrical conductivity and hydrophilicity of PAni-CNTs and their EP composites were strongly affected by the surface treatment of the CNTs. The surface-treating materials remained on the surface of the CNTs affected the reactivity of the CNTs surface to PAni, and thus resulted in different PAni amounts in the PAni-CNTs. The electrical conductivity of the PAni-CNTs/EP composites decreased, but the hydrophilicity increased, with increasing the amount of PAni coating on the CNTs surface. [Copyright &y& Elsevier]

Abstract: A composite hydrogel (CH) with much improved mechanical and swelling properties was prepared using an ionic monomer and acid-activated Laponite XLS which was used as a cross-linking agent. Addition of acid-activated clay solved the gelation problem when ionic monomers were added to clay mineral dispersions. Reaction of Laponite XLS with sulfuric acid yielded amorphous silica. A dispersion of the acid-activated Laponite and the monomers was used to synthesize composite hydrogels by in-situ polymerization. The FT-IR spectra and rheological results of the composite hydrogels demonstrated the formation of a network. The equilibrium swelling ratios of composite hydrogels (>6000g/g) were more than 18 times larger than traditional organic cross-linked hydrogels. The moduli G′ and G″ in the observed frequency range were about 4 and 10 times larger than those of organic cross-linked hydrogel (OR gel). The improvement in both the equilibrium swelling ratio and mechanical strength was attributed to the homogeneous cross-linked network structure. [Copyright &y& Elsevier]

Abstract: This study presents the features of profile evolution in deep trench silicon etching, which is crucial for commercial wafer-processing applications. Experiments to minimize the macroscopic and microscopic loading effects were performed with anisotropic deep trench etching in high-density decoupled HBr/CF4/Cl2/O2 and SF6/CF4/O2 plasmas. The process parameters, including gas chemistry, pressure, source power, bias power, and dual electrostatic chuck system, were also optimized for these applications. Notching and trenching phenomena were effectively improved during the deep trench etching process. The optimized deep trench silicon process resulted in vertical profiles (87–90°) with a loading effect of <1% by using the SF6-based chemistry, which was more effective than the HBr-based process. The bias constant verified the linear-etching parameter system, depending on the pattern density of the device, in order to commercialize deep trench silicon etching for mass production. [Copyright &y& Elsevier]

Abstract: In this study, an investigation is carried out on the influence of varying clay contents (25–43%), pH values (2–11 buffer solutions), heat treatment, temperatures (25–60°C) and ionic strengths (saline solution, 10−7–0.1M) on the water absorbency of polyacrylamide (PAAm)/laponite nanocomposite (NC) hydrogels in the absence of polyelectrolyte. For the influence of pH value on swelling behaviors, a maximum swelling ratio occurs at pH 11. Heat treatment of the hydrogels significantly improved the swelling capacity and created an obvious pH sensitive area (pH 3–4). The swelling capacity of the hydrogels was enhanced by increasing the temperature of the absorbing media. The results of swelling at different ionic strengths also indicate that the ionic strength can considerably weaken the swelling abilities of the NC hydrogels. [Copyright &y& Elsevier]

Gas-insulated switchgears (GISs) are important pieces of power equipment used to improve the reliability of power facilities. As the number of GISs increases, more insulation failures occur every year. The most common cause of insulation failure is particles and foreign bodies producing a partial discharge (PD), which causes deterioration of the insulation materials and results in insulation breakdown. However, it is not easy to detect them by conventional PD and ultra-high frequency (UHF) PD measurements because it is difficult to apply the conventional method to the GISs in service, and the UHF method is not always applicable to GISs. Therefore, an appropriate method to detect particles and foreign bodies in GISs is needed. In this study, experimental validation was performed to detect particles moving in GISs using the acoustic emission (AE) method. Acoustic wave signals were produced by the particles moving on the surface of a flat plate when applying voltage. An AE sensor with a frequency range of 50 to 400 kHz was used, and a decoupler and low-noise amplifier were designed to detect the acoustic wave signals with high sensitivity. Twelve types of particles were used, and one was selected to confirm the detectable minimum output voltage. In an actual factory test, the output voltage of the acoustic wave signals was analyzed while considering the applied voltage and signal attenuation. Consequently, it was confirmed that the AE measuring system proposed in this paper could detect particles moving inside GISs. [ABSTRACT FROM AUTHOR]

Abstract: The key component of ferroelectric random access memory (FeRAM) is a capacitor including a ferroelectric thin film and electrode materials. Platinum is one of the suitable metals which meet requirements such as low resistivity, high thermal stability, and good oxygen resistance. Generally, the ferroelectric and the electrode materials were patterned by a plasma etching process. The application possibility of chemical mechanical polishing (CMP) processes to the patterning of ferroelectric thin film instead of plasma etching was investigated in our previous study for improvement of an angled sidewall which prevents the densification of FeRAM. In this study, the characteristics of platinum CMP for FeRAM applications were also investigated by an approach as bottom electrode materials of ferroelectric material in CMP patterning. The removal rate was increased from 24.81nm/min by the only alumina slurry (0.0wt% of H2O2 oxidizer) to 113.59nm/min at 10.0wt% of H2O2 oxidizer. Electrochemical study of platinum and alumina slurry with various concentrations of H2O2 was performed in order to investigate the change of the removal rate. The decreased particle size in the alumina slurry with an addition of 10.0wt% H2O2 oxidizer made the improved surface roughness of the platinum thin films. Micro-scratches were observed in all polished samples. [Copyright &y& Elsevier]

Abstract: In order to improve the interconnect performance, copper has been used as the interconnect material instead of aluminum. One of the advantages of using copper interconnects instead of aluminum is better electromigration (EM) performance and lower resistance for ultralarge-scale integrated (ULSI) circuits. Dual-damascene processes use different approaches at the via bottom for lowering the via resistance. In this study, the effect of a Ta/TaN diffusion barrier on the reliability and on the electrical performance of copper dual-damascene interconnects was investigated. A higher EM performance in copper dual-damascene structures was obtained in barrier contact via (BCV) interconnect structures with a Ta/TaN barrier layer, while a lower EM performance was observed in direct contact via (DCV) interconnect structures with a bottomless process, although DCV structures had lower via resistance compared to BCV structures. The EM failures in BCV interconnect structures were formed at the via, while those in DCV interconnect structures were formed in the copper line. The existence of a barrier layer at the via bottom was related to the difference of EM failure modes. It was confirmed that the difference in EM characteristics was explained to be due to the fact that the barrier layer at the via bottom enhanced the back stress in the copper line. [Copyright &y& Elsevier]

Abstract: Ferroelectric thin films such as Pb(Zr,Ti)O3, SrBi2Ta2O9, and Bi3.25La0.75Ti3O12 (BLT) thin films have been widely investigated for non-volatile ferroelectric memories. BLT thin films show advantages such as highly fatigue resistance, low processing temperature, and large remanent polarization. The patterning of these ferroelectric thin films with a vertical sidewall and without plasma damage is strongly required. Chemical mechanical polishing (CMP) process was investigated for the vertical sidewall patterning of BLT thin films. Removal rate and within-wafer non-uniformity (WIWNU%) were examined by change of process parameters. Potential of hydrogen (pH) in slurry was varied for an improvement of the removal rate and WIWNU%. Surface roughness of BLT thin films after CMP process for the improvement of densification was inquired into by atomic force microscopy. The excellent performance such as 188.4 nm/min of removal rate, 2.61% of WIWNU%, 0.95 nm of root mean square roughness, and 6.94 nm of peak-to-valley roughness was obtained. This result will lead the CMP process to pattern the BLT thin films for the vertical sidewall without plasma damage. [Copyright &y& Elsevier]

Abstract: Micrometer-sized Ag (μAg) powders are very efficient substrates for both the infrared and Raman spectroscopic characterization of molecular adsorbates assembled on silver. In particular, the Raman spectrum of organic monolayers on μAg powders is a surface-enhanced Raman scattering (SERS) spectrum. To use μAg powders as a core material for constructing molecular sensing/recognition units operating via SERS, it is first necessary to stabilize the SERS-marker molecules that are directly in contact with the μAg powders. One promising strategy is the fabrication of silica shells onto SERS-marker molecules, and herein we demonstrate its feasibility by choosing 4-mercaptophenol (4-MPH) as a model SERS-marker molecule. Due to the presence of the hydroxyl group of 4-MPH, silica was readily deposited onto μAg particles by the base-catalyzed hydrolysis of tetraethyl orthosilicate, and its subsequent condensation, to form a cagelike structure. The formation of silica shells was confirmed with infrared, Raman, and X-ray photoelectron spectroscopy, coupled with field emission scanning electron microscopy. We were able to tune the thickness of silica shells simply by varying the silanization reaction time. [Copyright &y& Elsevier]

Abstract: In this study, we demonstrate that powders of commercially available 2-μm-sized Ag (μAg) can be used as a core material for constructing molecular sensing/recognition units operating via surface-enhanced Raman scattering (SERS). This is possible because μAg powders are very efficient substrates for both the infrared and Raman-spectroscopic characterization of molecular adsorbates prepared in a similar manner on silver surfaces. The Raman spectrum of organic monolayers on powdered silver is a SERS spectrum. The agglomeration of μAg particles in a highly concentrated buffer solution could be prevented by the deposition of polar molecules like 1,4-phenylenediisocyanide (1,4-PDI), and mixed self-assembled monolayers of 1,4-PDI and N-(+)-biotinyl-6-aminocaproic acid on μAg particles were then confirmed via the SERS of 1,4-PDI to selectively recognize the avidin arrays formed on a separate biotinylated substrate. According to a dose response curve, avidin at >10−6 g/mL could be easily identified by the present method. In addition, the non-specific adsorption of μAg particles was found to be negligibly small, probably because the Ag particles were too heavy to be retained on organic substrates solely by non-specific interaction. [Copyright &y& Elsevier]

Abstract: Most high-k materials cannot to be etched easily. Problems such as low etch rate, poor sidewall angle, plasma damage, and process complexity have emerged in high-density DRAM fabrication. Chemical mechanical polishing (CMP) by the damascene process has been used to pattern high-k materials for high-density capacitor. Barium titanate (BTO) thin film, a typical high-k material, was polished with three types of silica slurry having different pH values. Sufficient removal rate with adequate selectivity to realize the pattern mask of tetra-ethyl ortho-silicate (TEOS) film for the vertical sidewall angle was obtained. The changes of X-ray diffraction pattern and dielectric constant by CMP process were negligible. Planarization was also achieved for the subsequent multilevel processes. Our new CMP approach will provide a guideline for effective patterning of high-k materials by CMP. [Copyright &y& Elsevier]