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Water scarcity is one of the most critical problems that humans have to face. Working toward solving this problem, we have developed a thin-film composite (TFC) membrane using the modified molecular layer-by-layer (modified mLBL) method to fabricate polyamide (PA) active layers on different substrates. Besides, it has been found that graphene oxide (GO) contains abundant functional groups such as hydroxyl and epoxide groups, which are able to improve both the physical and chemical properties of the forward osmosis (FO) membrane. Thus, we have employed graphene oxide (GO) as the substrate and used the modified mLBL method to prepare active polydopamine/graphene oxide (PDA/GO) layers to enhance the water flux of the forward osmosis (FO) membrane. PDA/GO-coated layers could enhance the hydrophilic nature of the substrate and lower its surface roughness, which would facilitate the formation of the PA layer. Moreover, the PDA/GO coating can be applied to all substrates because of the high degree of adhesion of PDA to different substrates. In this study, the highly hydrophilic poly(vinylidene fluoride) membrane is superior in FO properties, with a water flux of 17.32 LMH and a reverse solute flux of 4.34 gMH. In addition, an excellent performance of 60.15 LMH and 14.88 gMH can be achieved when the pressure-retarded osmosis (PRO) test mode with a draw solution concentration of 2.0 M is used in the test. It shows that the membrane prepared using the novel method showed excellent FO performance, which has high potential in industrial applications such as desalination., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

In this work, we report the fabrication and performance of supercapacitors made from carbonized peanut shells, which are renewable materials with a huge annual yield and are usually discarded directly by people. With proper treatment, peanut shells could be used for many applications. Herein, we demonstrate that the peanut shells treated with carbonization and activation processes not only possess an extremely high surface area but also provide a hierarchical structure for energy storage. The performance of the electrode can be further improved by nitrogen doping and adding graphene oxide to the electrode. The electrode shows a specific capacitance of 289.4 F/g, which can be maintained at an acceptable level even at a high scanning rate. In addition, a good capacitance retention of 92.8% after 5000 test cycles demonstrates that the electrode possesses an excellent electrochemical property., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Excessive phosphorus in water is the primary culprit for eutrophication, which causes approximately $2.2 billion annual economic loss in the United States. This study demonstrates a phosphate-selective sustainable method by adopting Garcinia subelliptica leaves as a natural bio-template, where MgMn-layered double hydroxide (MgMn-LDH) and graphene oxide (GO) can be grown in situ to obtain L-GO/MgMn-LDH. After calcination, the composite shows a hierarchical porous structure and selective recognition of phosphate, which achieves significantly high and recyclable selective phosphate adsorption capacity and desorption rate of 244.08 mg-P g -1 and 85.8%, respectively. The detail variation of LDHs during calcination has been observed via in situ transmission electron microscope (TEM). Moreover, the roles in facilitating phosphate adsorption and antimicrobial ability of chemical constituents in Garcinia subelliptica leaves, biflavonoids, and triterpenoids have been investigated. These results indicate the proposed bio-templated adsorbent is practical and eco-friendly for phosphorus sustainability in commercial wastewater treatment., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

A new synthetic method to grow O-deficient rutile TiO 2(s) nanorods (NRs) and nanowires (NWs) by a vapor-solid reaction growth method is developed. TiCl 4(g) was employed to react with commercially supplied CaTiO 3(s) (size 2-4 μm) at 973 K under atmospheric pressure to generate TiO 2(s) NRs (diameters 80-120 nm, lengths 1-4 μm). The reaction employing TiCl 4(g) and CaO (s) at 973 K also generated CaTiO 3(s) (size 4-13 μm) as the intermediate which reacted further with TiCl 4(g) to produce NWs (diameters 80-120 nm, lengths 4-15 μm). This is the first report of 1D rutile TiO 2(s) nanostructure with such a high aspect ratio. Both of the NRs and the NWs, with compositions TiO 1.81 and TiO 1.65 , respectively, were single crystals grown in the [001] direction. Their morphology was affected by the reaction temperature, the concentration of TiCl 4(g) , and the particle size of CaTiO 3(s) . The NRs and the NWs were investigated as anode materials for Li + -ion batteries. At constant current rates 1, 2, and 5 C (1 C = 170 mA g -1 ) for 100 cycles, the cycling (1.0-3.0 V) performance data of the NRs were 146, 123, and 104 mA h g -1 , respectively. On the other hand, the cycling performance data of the NWs were 120, 80, and 52 mA h g -1 , respectively. This is attributed to the high Li + ion diffusion rate ( D Li + ) of the NRs (29.52 × 10 -15 cm 2 s -1 ), which exceeds that of the NWs (8.61 × 10 -15 cm 2 s -1 ). Although the [001] growth direction of the NR crystals would provide the fastest channels for the diffusion of Li + ions and enhance the battery capacity, the extremely long channels in the NWs could hamper the diffusion of the Li + ions. The O-deficiency in the structure would increase the conductivity of the electrode material and improve the stable cycling stability of the batteries also. The long-term cycling test at 2 C for the battery constructed from the NRs retained 121 mA h g -1 after 200 cycles and 99.2 mA h g -1 after 800 cycles. The device has an excellent long-term cycling stability with a loss of only 0.04% per cycle., Competing Interests: The authors declare no competing financial interest., (Copyright © 2019 American Chemical Society.)

Objectives: The validity of instruments measuring socioeconomic position (SEP) has been a major area of concern in research on cardiovascular health disparities. The purpose of this systematic review is to identify the current status of the methods used to measure SEP in research on cardiovascular health disparities in Korea and to provide directions for future research., Methods: Relevant articles were obtained through electronic database searches with manual searches of reference lists and no restriction on the date of publication. SEP indicators were categorized into compositional, contextual, composite, and life-course measures., Results: Forty-eight studies published from 2003 to 2018 satisfied the review criteria. Studies utilizing compositional measures mainly relied on a limited number of SEP parameters. In addition, these measures hardly addressed the time-varying and subjective features of SEP. Finding valid contextual measures at the organizational, community, and societal levels that are appropriate to Korea's context remains a challenge, and these are rarely modeled simultaneously. Studies have rarely focused on composite and life-course measures., Conclusions: Future studies should develop and utilize valid compositional and contextual measures and appraise social patterns that vary across time, place, and culture using such measures. Studies should also consider multilevel influences, adding a focus on the interactions between different levels of intertwined SEP factors to advance the design of research. More attention should be given to composite and life-course measures.

The glucose level is an important biological indicator for diabetes diagnosis. In contrast with costly and unstable enzymatic glucose sensing, oxide-based glucose sensors own the advantages of low fabrication cost, outstanding catalytic ability, and high chemical stability. Here, we fabricate a self-supporting spiky Cu x O/Cu nanowire array structure by electrochemical cycling treatment. The spiky Cu x O/Cu nanowire is identified to be a Cu core passivated by a conformal Cu 2 O layer with extruded CuO petals, which provides abundant active sites for electrocatalytic reaction in glucose detection. An interruptive potential sweeping experiment is presented to elucidate the growth mechanism of the spiky Cu x O/Cu nanostructure during the potential cycling treatment. The spiky Cu x O/Cu nanowire array electrode exhibits a sensitivity of 1210 ± 124 μA·mM -1 ·cm -2 , a wide linear detection range of 0.01-7 mM, and a short response time (<1 s) for amperometric glucose sensing. The study demonstrates a route to modulate oxide phase, crystal morphology, and electrocatalytic properties of metal/oxide core-shell nanostructures., Competing Interests: The authors declare no competing financial interest.

An Au/K bicatalyst-assisted chemical vapor deposition process using C 2 H 2(g) to grow high-density carbon nanocoils (CNCs) uniformly on the fibers in carbon fiber cloth substrates three-dimensionally was developed. An as-deposited substrate (2.5 × 1.0 cm 2 ) showed a high electrochemical active surface area (16.53 cm 2 ), suggesting its potential usefulness as the electrode in electrochemical devices. The unique one-dimensional (1D) helical structure of the CNCs shortened the diffusion pathways of the ions in the electrolyte and generated efficient electron conduction routes so that the observed serial resistance R s was low (3.7 Ω). By employing two-electrode systems, a liquid-state supercapacitor (SC) in H 2 SO 4(aq) (1.0 M) and a solid-state SC with a polypropylene (PP) separator immersed in H 2 SO 4(aq) (1.0 M)/polyvinylalcohol were assembled and investigated by using CNC-based electrodes. Both devices exhibited approximate rectangular shape profiles in the cyclic voltammetry measurements at various scan rates. The observations indicated their electric double-layer capacitive behaviors. From their galvanostatic charge/discharge curves, the specific capacitances of the liquid SC and the solid SC were measured to be approximately 137 and 163 F/g, respectively. In addition, the solid-state CNC-based SC possessed excellent energy density (15.3 W h/kg) and power density (510 W/kg). The light weight solid SC (0.1965 g, 2.5 × 1.0 cm 2 ) was bendable up to 150° with most of the properties retained., Competing Interests: The authors declare no competing financial interest.

In this paper, nitrogen incorporated ultrananocrystalline diamond (NUNCD) films were fabricated for use as electrodes to detect dopamine. The NUNCD electrodes achieved high sensitivity, great selectivity, and excellent detection limits for dopamine sensing. The NUNCD electrode, fabricated as a potential sensitive biosensor for dopamine without any catalyst or mediators, demonstrated good activity for the direct detection of dopamine by simply putting the bare NUNCD electrode into a dopamine solution. Furthermore, the marked selectivity of the NUNCD electrode is very favorable for the determination of dopamine (DA) concentration (0.32 μM) in the presence of ascorbic acid (AA) and uric acid (UA). Considering dopamine detection in real biological fluid samples, the NUNCD electrode performed excellently with a detection limit of 0.39 μM and a high recovery ranging from 90-120%, revealing that NUNCD electrodes have promising use in the sensing of dopamine.

In this study, we develop a new synthetic method to grow anatase TiO 2 crystals composed of truncated octahedral bipyramids (TOBs) with exposed {001} and {101} facets by a vapor-solid reaction growth (VSRG) method. The VSRG method employs TiCl 4(g) to react with CaO (s) /Ca(OH) 2(s) at 823-1043 K under atmospheric pressure. The O-deficient pale-blue TOB TiO 2 crystals display high amount of both {001} and {101} facets. Together, they decompose methylene blue photocatalytically under UV-visible (UV-vis) light irradiation. The most-efficient TOB catalyst VT923 (grown at 923 K, average edge length 400 nm, average thickness 200 nm, and surface area 4.20 m 2 /g) shows a degradation rate constant k , 0.0527 min -1 . This is close to that of the P25 standard 0.0577 min -1 . However, the surface area of P25 (46.8 m 2 /g) is about 12 times that of VT923. The extraordinary performance of VT923 is attributed to the presence of high amount of coexisting {001} and {101} facets to form effective surface heterojunctions. They would separate photogenerated electrons and holes effectively on {101} and {001} surfaces, respectively. For VT923, the {001}/{101} ratio is 0.764, which is close to 1, the highest value observed for all TOB samples grown in this study. The surface heterojunctions prolong the electron-hole separation so that VT923 demonstrates the excellent photocatalytic capability. In addition, residual Cl atoms on the exposed faces are easily removed to show clean TiO surface layers with sufficient amount of O-deficient sites in the current samples., Competing Interests: The authors declare no competing financial interest.

We report a versatile strategy to exploit parafilm waste as a carbon precursor for fabrication of freestanding, hollow few-layer graphene fiber mesh (HFGM) structures without use of any gaseous carriers/promoters via an annealing route. The freestanding HFGMs possess good mechanical flexibility, tailorable transparency, and high electrical conductivity, consequently qualifying them as promising electrochemical electrodes. Because of the hollow spaces, electrolyte ions can easily access into and contact with interior surfaces of the graphene fibers, accordingly increasing electrode/electrolyte interfacial area. As expected, solid-state supercapacitors based on the HFGMs exhibit a considerable enhancement in specific capacitance (20-30 fold) as compared to those employing chemical vapor deposition compact graphene films. Moreover, the parafilm waste is found to be beneficial for one-step fabrication of nanocarbon/few-layer graphene composite meshes with superior electrochemical performance, outstanding superhydrophobic property, good self-cleaning ability, and great promise for oil spill cleanup.

Ampullary adenoma is a common indication for endoscopic papillectomy. Ampullary neuroendocrine tumor (NET) is a rare disease for which complete surgical resection is the treatment of choice. However, because of the morbidity and mortality associated with surgical resection, endoscopic papillectomy is increasingly used in selected cases of low grade, with no metastasis and no invasion of the pancreatic or bile duct. Also, confirmed and complete endoscopic resection of ampullary NET accompanied by adenoma has not been reported to date. We report herein a rare case of an ampullary NET accompanied with adenoma, which was successfully and completely resected via endoscopic papillectomy. Prior to papillectomy, this case was diagnosed as an ampullary adenoma.

N2 incorporated diamond nanowire (N-DNW) film electrochemical biosensor has utilized for the quantitative determination of urea in aqueous solution and urine sample. N-DNW electrode is wet-chemically cleaned (oxidation) by boiling in a mixture of H2SO4 and HNO3 (3:1) at 200°C for 2h to remove graphite. Urease (Urs) and glutamate dehydrogenase (GLDH) are covalently attached to the oxidized N-DNW electrode by activating the COOH group of N-DNW using ethyl(dimethylaminopropyl)carbodiimide as the coupling agent and N-hydroxysuccinimide as activator. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy data reveal that carboxylic and hydroxyl functionalized nature of N-DNW electrodes Urs-GLDH immobilized N-DNW (Urs-GLDH/N-DNW) has been successfully utilized in urea biosensor which exhibits good performance in sensitivity (6.18 μA/mg dL/cm(2)), stability (~1 month), reproducibility, lower detection limit (3.87 mg/dL) and fast response time (>10s). Urs-GLDH/N-DNW also exhibits electrochemical response when tested for different concentration of human urine in buffer solution (from 1:9 to 4:6). In addition, Urs-GLDH/N-DNW bioelectrode retains 80% of its initial enzyme activity for <1 month, when stored at 4-6°C in a refrigerator., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The electrocatalytic properties of a N2 incorporated diamond nanowire (N-DNW) unmodified electrode towards the oxidation of nicotinamide adenine dinucleotide (NADH) was critically evaluated. The electrochemical behavior of the N-DNW unmodified electrode was examined and compared with that of boron-doped diamond, glassy carbon electrode, and graphite electrodes. The N-DNW electrode had high selectivity and high sensitivity for the differential pulse voltammetric detection of NADH in the presence of ascorbic acid at the lower and stable oxidation potential. Moreover, it exhibited strong stability after prolonged usage. The oxidation peak potential at the N-DNW electrode remained unchanged even after exposure to the solution, followed by washing, drying, and storage in laboratory air for 20 days, with minimization of surface contamination. Therefore, the N-DNW unmodified electrode shows promise for the detection of NADH and is attractive for use in a dehydrogenase based biosensor and other analytical applications.

Vertically aligned conducting ultrananocrystalline diamond (UNCD) nanorods are fabricated using the reactive ion etching method incorporated with nanodiamond particles as mask. High electrical conductivity of 275 Ω·cm-1 is obtained for UNCD nanorods. The microplasma cavities using UNCD nanorods as cathode show enhanced plasma illumination characteristics of low threshold field of 0.21 V/μm with plasma current density of 7.06 mA/cm2 at an applied field of 0.35 V/μm. Such superior electrical properties of UNCD nanorods with high aspect ratio potentially make a significant impact on the diamond-based microplasma display technology.

C(6)F(6) vapor is employed to react with CaC(2) and Mg(3)N(2) to grow CaF(2)/a-C and Mg(2)F(2)/a-C core/shell nanowires (tens of micrometers in length, tens to hundreds of nanometers in wire diameter, and tens of nanometers in core diameter), respectively, in high yields. The growth mechanism is proposed to proceed via a reaction at the interface of the vapor and solid reactants.

The authors would record the fifth case of human fascioliasis in Korea, occurring in a 48 year old Korean man who lived in Munkyong, Kyongsangbuk-do. The diagnosis was based on the morphology and measurements of the eggs which were collected in necrotic debris from the tunnel-like ulcerations of the gallbladder wall which was surgically removed for a gall stone. Although we failed to find out the fluke in the specimen, there found an evidence of once presence of Fasciola in the inflamed wall of the gallbladder in this patient.