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A flexible radio-frequency (RF) antenna allows wearable smart devices to have various functionalities. To develop a high-performance RF antenna, an outstanding radiation efficiency should be achieved. Metallic films are commonly utilized in RF antenna electrodes owing to their high electrical conductivity, which is related to the radiation efficiency. However, their high density and low mechanical stability under deformed states, such as the folding of metallic films, hinder their use as flexible RF antenna electrodes. In this study, we fabricated a carbon-nanotube (CNT) film via the direct-spinning method for use in a flexible RF antenna electrode. The network structure of the CNT film endows it with a high electrical conductivity and allows it to be freestanding without a polymeric binder. The freestanding CNT film-based RF antenna attained a high radiation efficiency of 85.6%, commercially useable level, and its performance remained stable even under mechanical deformation, such as bending and folding. This high performance is attributed to the network structure of the CNT film composed of pure CNT bundles.

A functionalized phosphorene/polypyrrole (FPPY) hybrid nanomaterial was prepared via a mechanochemical process and chemical oxidative polymerization. The polymerization of polypyrrole (PPY) on the surface of two-dimensional phosphorene was investigated in detail. The amide bond formation of the FPPY hybrid improved the interfacial interaction between the PPY and phosphorene. The specific capacitance of the FPPY was 411.5 F g−1, which was approximately four times that of pristine PPY (106 F g−1). Additionally, hybridization improved the structural stability of PPY, yielding a cycle stability 2 times higher than that of pristine PPY. To the best of our knowledge, this is the first report on the potential of phosphorene hybridized with conducting polymers for practical energy-storage applications.

The effect of phase transition and exfoliation time on electro-responsive behavior of black phosphorus is identified by introducing black phosphorus and phosphorene to electrorheological fluid. Black phosphorus is successfully fabricated by mechanical milling for phase transition from red phosphorus, and phosphorene is fabricated by ultrasonication of the prepared black phosphorus. The morphology, degree of phase transition, and electrical conductivity of black phosphorus and phosphorene are precisely controlled by modifying the duration of both milling and delamination. It can be corroborated from a comprehensive study that the electrical conductivity as well as morphology affect the electro-responsive behaviors of black phosphorus and phosphorene. To the best of our knowledge, this is the first report on the meticulous control of phase transition and the potential of both black phosphorus and phosphorene as candidate materials for lectrorheological fluids. This study may provide understanding of the electro-responsive characteristics of black phosphorus and phosphorene, broadening the perspective of electro-responsive smart fluids.

A highly transparent and high-performance random-network single-walled carbon nanotubes (r-SWCNTs) transistor was successfully fabricated by using chemical vapor deposition-grown graphene source/drain (S/D) electrodes. The bottom-gate, bottom-contact geometry was selected for the graphene S/D contact r-SWCNT (Gr-SWCNT) transistor because of its enhanced gate modulation and good sustainability. A palladium S/D contact r-SWCNT (Pd-SWCNT) transistor with the same device geometry was also fabricated for a comparative study. The transmission line method demonstrated that the resistivity of graphene was small enough (∼0.95 Ω μm) to be used as S/D electrodes in a single transistor device, and the contact resistance of Gr-SWCNTs was much lower than that of Pd-SWCNTs. Particularly, the correlation between the applied gate voltage and the sheet resistance is strongly dependent on the r-SWCNT film density. The resulting Gr-SWCNT transistor exhibits high mobility and good on/off current ratio compared to the Pd-SWCNT transistor. The high charge injection originated from the ohmic contact behavior and dense r-SWCNT channel formation by the enhancement of selective wetting due to the surface energy matching between the r-SWCNT semiconductor and graphene S/D electrodes. Thus, this approach can encourage creating highly transparent and high-performance carbon-based field effect transistor.

In this study, we aimed to analyze patient mortality rate after non-operative treatment of hip fractures to determine the distribution of causes of death and to compare factors affecting mortality.Between January 2013 and March 2019, a total of 93 patients (17 males, 76 females; mean age: 86.0±7.4 years; range, 64 to 98 years) who had hip fractures and were treated non-operatively were analyzed retrospectively. Survival, date of death, and cause of death were collected and analyzed. Baseline demographics, pre-trauma ambulation, pre- and post-trauma residence status, American Society of Anesthesiologists Physical Status (ASA PS) classification, and Parker's mobility score were compared with one-year mortality rates.The mean follow-up of survivors was 16.1±11.9 (range, 6.3 to 79.6) months. The mean survival of non-survivors was 4.9±6.1 (range, 0.007 to 27.3) months. The 3-, 6-, 12-, and 24-month mortality rates were 40.9%, 53.3%, 74.4%, and 87.5%, respectively. Respiratory diseases (33.3%) and cardiovascular diseases (13.6%) were the main causes of death among the patients. There was no statistically significant difference between the patients' age, sex, fracture site, pre-trauma ambulation, pre- and post-trauma residence status, ASA PS classification, Parker's mobility score, and one-year mortality.A significant number of patients are still treated non-operatively after hip fractures, and they have a high mortality rate. Efforts and research are needed to reduce mortality and improve the quality of life.

In this study, based on three-dimensional (3D) framework architecture built-up with two-dimensional (2D) graphitic carbon such as graphene, we have prepared a mechanically robust polymer composite without exhibiting notable deterioration of electrical conductivity under mechanical deformation. In constructing 3D framework comprising of graphitic carbons, two sophisticated methodologies, direct formation of graphitic layers on metal foam by chemical vapor deposition (CVD), and lay-up of reduced graphene oxide (rGO) nanosheets on metal foam have been performed, respectively, and their sustainability of conductive performance under mechanical deformation has been comparatively examined in terms of electrical conductivity change by cyclic mechanical stress. The CVD-synthesized graphene (CGr) framework-embedded PDMS composite, which means a PDMS composite containing 3D graphene framework grown by CVD process, exhibited electrical conductivity of ∼5 S/m at graphene content of 1.0 wt%, which was ∼5 orders of magnitude higher than that of 3D rGO framework-embedded PDMS composite containing comparable loading of rGO. When subjected to repetitive mechanical stress, it was found that the superior conductivity performance of CGr framework over rGO framework was well retained, presumably due to the higher perfectness of graphitic layers, which would impart much longer electron transfer to the framework architecture of graphitic carbon nanosheets.

Vertically aligned TiO2/ZnO nanotube (NT) arrays were developed for application to photoanodes in mesoscopic solar cells. By a two-step anodic oxidation, vertically aligned TiO2 NT arrays with highly ordered surface structure were prepared, followed by deposition of a ZnO shell with a precisely controlled thickness using atomic layer deposition (ALD). When applied to a photoanode of dye-sensitized solar cells (DSSCs), the photovoltage is gradually enhanced as the ZnO shell thickness of the TiO2/ZnO NT electrodes is increased. Furtheremore, the electron lifetime in photoanodes is significantly enhanced due to the ZnO shell, which is examined by open-circuit voltage decay (OCVD) measurement. Photocurrent density-voltage (J-V) curves under the dark condition and OCVD spectra reveal that a negative shift in TiO2 conduction band potential and an energy barrier effect owing to the ZnO shell concurrently contribute to the enhancement of VOC and electron lifetime.

We report a facile approach for producing highly omnidirectional and frequency tunable antennas based on multilayer graphene/multi-walled carbon nanotube (MG/MWNTs) electrodes. The MG sheets are obtained by ball milling graphite, followed by sonication. Monopole patch antennas are prepared by screen printing the MG/MWNTs paste onto a polymer substrate. The resulting antennas show excellent performance due to the bridge effect of the MWNTs between well-dispersed adjacent MG layers, which increases the contact area between MG sheets along the horizontal and vertical axes. The antennas formed from the MG/MWNTs exhibit smaller return losses than the antennas formed from pristine graphite, as well as high radiation efficiency (∼44.9%). Moreover, the MG/MWNTs antennas require a relatively small quantity, which leads to low production costs. In addition, the dimensions of the antennas can be simply adjusted by controlling the screen printing mask or cutting with scissors to achieve frequency tunability. These results demonstrate the potential of these MG/MWNTs antennas for applications in wireless communications for ubiquitous sensor networks.

To the best of our knowledge, the study described herein is the first to demonstrate the use of amorphous Sn–Ni islets as an anode material for lithium-ion storage. The islets are prepared by co-electrodeposition (2 s). In general, amorphous Sn–metal alloys exhibit significantly improved cycling performances over those of crystalline alloys with similar compositions and morphologies. However, to date, no thermodynamically metastable amorphous phase has been found in Sn–Ni alloys of any composition. Here, we show that the amorphization of such alloys is possible by ensuring rapid co-electrodeposition, so as to prevent Sn and Ni from crystallizing. The resulting amorphous Sn–Ni alloy affords suppressed capacity degradation due to the preservation of its initial microislet-shaped particles and its structural integrity after cycling. This is primarily due to the volume changes in the amorphous phase being small. These findings indicate the potential of this newly developed amorphous Sn–Ni alloy to be used as an anode material for lithium-ion rechargeable batteries.

Molybdenum disulfide (MoS2) incorporated with a conducting polymer can be a promising nanomaterial for use as low-cost electrodes in supercapacitors. MoS2 nanosheets are generally prepared by the high-pressure hydrothermal method, which has a few drawbacks such as low exfoliation yield, safety issues, and long-time processing. Herein, we report a simple and effective method for the high-yield (~72.5%) preparation of a MoS2/polypyrrole (MPY) hybrid nanomaterial via sonochemical exfoliation of ground bulk MoS2 in a polar aprotic solvent and subsequent chemical oxidative polymerization of pyrrole (PY) onto the MoS2 nanosheets. The strong non-covalent Mo–N bonding lowers the interfacial resistance, and the morphology of polypyrrole (PPY) can be easily controlled by varying the PY content. The MPY hybrid nanomaterial exhibited a maximum surface conductivity of 991 S sq., which is very high compared to that of pristine MoS2 nanosheet (~3.6 × 10–7 S sq.). When used in supercapacitors, the specific capacitance of the hybrid nanomaterial is 312 F g–1. Thus, improved capacitance retention with increase in the scan rate and enhanced diffusion process during electrochemical reactions result in good supercapacitor performance, which is important for the mass production of energy-storage devices.

Multilevel data storage using resistive random access memory (RRAM) has attracted significant attention for addressing the challenges associated with the rapid advances in information technologies. However, it is still difficult to secure reliable multilevel resistive switching of RRAM due to the stochastic and multiple formation of conductive filaments (CFs). Herein, we demonstrate that a single CF, derived from selective oxidation by a structured Cu active electrode, can solve the reliability issue. High-quality pyramidal Cu electrodes with a sharp tip are prepared via the template-stripping method. Morphology-dependent surface energy facilitates the oxidation of Cu atoms at the tip rather than in other regions, and the tip-enhanced electric fields can accelerate the transport of the generated Cu ions. As a result, CF growth occurs mainly at the tip of the pyramidal electrode, which is confirmed by high-resolution electron microscopy and elemental analysis. The RRAM exhibits highly uniform and low forming voltages (the average forming voltage and its standard deviation for 20 pyramid-based RRAMs are 0.645 and 0.072 V, respectively). Moreover, all multilevel resistance states for the RRAMs are clearly distinguished and show narrow distributions within 1 order of magnitude, leading to reliable cell-to-cell performance for MLC operation.

The state-of-the-art of the Internet of things (IoT) and smart electronics demands advances in thin and flexible radio frequency (RF) antennas for wireless communication systems. So far, nanostructured materials such as metals, carbon nanotubes, graphene, MXene, and conducting polymers have been investigated due to their noteworthy electrical conductivity. However, most antennas based on metallic materials are thick, which limits their application in miniaturized and portable electronic devices. Herein, we report two-dimensional (2D) metallic niobium diselenide (NbSe

Developing high-performance carbon-based flexible supercapacitors is crucial for energy-storage systems with high stability and safety. Here we report a succinct method of fabricating polypyrrole (PPY) by chemical vapour deposition polymerization on flexible graphene substrate. The dependency of initiators such as FeCl3 and CuCl2 for the polymerization of pyrrole is elucidated as well. The morphological changes as well as doping concentrations of PPY affect the capacitive behaviours of the nanocomposites. In addition, an assistance of dopamine between PPY and graphene not only improves the uniformity of PPY layers, but also enhances the supercapacitor performance. These results demonstrate the potential for the wearable energy-storage devices application.

Composite-based resistance switching random access memory (ReRAM) has great potential for application in flexible and wearable electronics. However, its large operating parameters and low reliability still have some limitations in realizing practical applications, which is derived from its high dependence on the orientation and dispersion of the filler in the composite layer. Here, we proposed a novel composite system that does not depend heavily on the orientation or dispersion of the fillers within the composite film of the ReRAM device. The AgNW/TiO2 core-shell nanowires inducing superb resistance switching behavior were fabricated. The composite resistance switching (RS) film was prepared by mixing the one-dimensional core-shell particles and poly (vinyl alcohol) (PVA) dielectric matrix. The composite RS film exhibited remarkable resistance switching behavior with extremely low/uniform operating voltage (Vset ~ 0.13 ± 0.013 V, and Vreset ~ −0.10 ± 0.012 V), and the reliable switching behavior was maintained for up to ~200,000 mechanical deformation cycles under 3 mm of bending radius. To evaluate the resistance switching mechanism of the composite-type ReRAM, the structural analysis and device modeling were performed.

Highly crumpled graphene-based three dimensional (3D) interconnected and hierarchically porous conducting networks were prepared for application as electrocatalytic counter electrode (CE) in dye-sensitized solar cells (DSSCs). Finely and hierarchically crumpled graphene was synthesized from Fe 2 O 3 /graphene oxide (GO) hybrids via a one-step chemical etching–reduction process with HI solution. The synthesized crumpled graphene exhibited not only 24 times higher specific surface area, but also superior dispersibility in aqueous solution compared to conventional reduced graphene oxide (rGO). Owing to its superior solution processability and comparable electrical conductivity, the crumpled graphene could be assembled into 3D interconnected films on the substrates simply by drop casting, without any binders. In addition, although the crumpled graphene was not modified by dopants or high-temperature annealing, it showed much higher electrocatalytic activity for the I − /I 3 − redox couple compared to that of rGO, which is mainly attributed to its significantly larger accessible surface area for electrochemical reduction. As a result, the DSSC containing the crumpled graphene CE exhibited 2.8 times enhanced conversion efficiency (η = 5.15%) compared to that containing a rGO electrode (η = 1.86%).

Vitamin D has received considerable attention in recent years owing to the increasing evidence of its importance in muscle function and physical performance. The present study attempted to determine whether patients with low serum vitamin D levels had impairment in early functional outcomes following total knee arthroplasty (TKA). This was a prospective cohort study that included 92 patients. Patients were divided into two groups according to their vitamin D levels as assessed at the preoperative visit: (1) vitamin D-deficient group, serum 25-hydroxyvitamin D3 (25(OH)D) levels

Highly sensitive, wearable and wireless pressure sensor was successfully fabricated based on the zinc oxide (ZnO) nanoneedle/poly(vinylidene difluoride) (PVDF) hybrid film. The nanoneedle structure of ZnO with large aspect ratio and hexagonal vertical grown pyramid form could lower the elastic modulus of the hybrid film compared to the ZnO nanorod. Due to its high permittivity, low polarization response time and outstanding durability, the hybrid film can be applied for a real-time pressure sensor to monitor the heart rate. Notably, the lowest detectable pressure of the hybrid film was as small as 4 Pa. Furthermore, the reduced graphene oxide (rGO) electrode-based Bluetooth antenna attained high peak gain (2.70 dBi) and radiation efficiency (78.38%), which was applicable to be used as an omnidirectional antenna to transmit wireless signal to the smart phone. Interestingly, the received wireless heart beat signal within a distance of 8 m was more sensitively measured on the radial artery than carotid artery without distortion and time delay, and it had a similar oscillation in comparison with the wire pressure sensor. This approach offers a valuable and promising tool for producing the commercial and continuous wireless pressure sensor for use in routine biomedical research and critical healthcare.

This paper proposes a new analysis of English partitives in which a quantifier is immediately followed by an of-phrase. It has been claimed that a partitive contains a null NP, analyzing the of-phrase as an adjunct. The null noun approach, however, does not adequately account for some important characteristics of English partitives. I argue that in a partitive, a quantifier takes an argument of type e, which is syntactically realized as a PP, and denotes a part-of relation. It is therefore proposed that a quantifier can take either an NP or a PP as its complement. I present diachronic evidence to support this dual-function analysis while explaining why every and no are not used with the partitive of-phrase. The proposed analysis has advantages over previous approaches that treat quantifiers in a uniform way.

Various polymer nanocomposites exhibiting elecro-conductivity along with flexibility were successfully fabricated by construction of the graphene-based three-dimensional (3-D) mesoporous skeleton platform derived from 3-D interconnected framework architecture constituted with two-dimensional (2-D) graphitic nanosheets, and the subsequent infiltration of polymer into pore volumes of the skeleton platform. The mesoporous 3-D skeleton platform of graphene has been easily constructed by the aggregation of graphene-coated polystyrene (PS) hybrid spheres prepared through ionic interacton between anionic graphene nanosheets and cationic PS nanospheres, and the subsequent thermal removal of polymer components, which made it possible to provide well-made pathways for electron transport as well as empty pores for the following infiltration of polymer matrix component. When a flexible polymer such as PVDF-HFP was chosen as a polymer matrix component entering into pore volumes of the graphene skeleton platform, the graphene/polymer nanocomposite tended to exhibit interesting behavior of electrical conductivity, which is comparable to that of neat graphene skeleton platform, and also maintained the initial value even under half-folding condition, evidencing excellent structural stability of the graphene skeleton. Furthermore, it was found that exchange of polymer matrix does not significantly alter the electrical conductivity of nanocomposite, confirming again the performance of 3-D graphene skeleton employing interconnected framework architecture as electron transport pathway. The ability to embed 3-D graphene skeleton into polymer matrix is a great opportunity to impart high electrical and mechanical properties to polymer composite formulation. Open image in new window

Graphene composites have great potential in electrical and electronic applications due to their outstanding physicochemical, electrical, and mechanical properties. Unfortunately, current graphene preparation technologies allow the exploitation of only an exceptionally low percentage of graphene’s capability. Herein, free-standing graphene films based on three-dimensional (3D) continuous structures of hollow graphene ellipsoids were successfully fabricated, whose composite structure has never been investigated. Positively charged polystyrene (PS) spheres were first wrapped with negatively charged graphene upon simple mixing, and became ellipsoids by stretching. Due to their improved continuity, composites based on the ellipsoids and spherical microparticles have lower sheet resistances than those based on spherical nanoparticles. Upon folding and application of pressure, composites based on the hollow graphene ellipsoids exhibited superior electrical conductivity and structural stability owing to their high mechanical strength and effective electron transport pathway. The ability to control the face-contact structures of graphene in a polymer matrix by means of particle morphology represents an effective strategy for future composite engineering.

It is argued that double access sentences are interpreted de re with respect to a state described by the embedded clause. The de re interpretation is manifested by postulating a tense movement. However, this de re analysis has some serious problems, as pointed out by Gennari (1999, 2003). As an alternative approach, Gennari (1999, 2003) and Altshuler & Schwarzchild (2013) propose that a double access reading is due to the semantics of the present tense without postulating any particular mechanism that applies to embedded tenses. In this squib, I argue that their uniform approach to embedded and non-embedded tenses also faces its own shortcomings, which can shed some new light on the interpretation of embedded tenses.

‡§ § § � � � ¶ ¶ † ‡ § � ¶ Background/Aims: Advances in endoscopic submucosal dissection (ESD) techniques have led to the development of expanded criteria for endoscopic resection of early gastric cancer (EGC). The aim of this study was to evaluate the short- and long-term outcomes for ESD using indication criteria. Methods: A total of 1,105 patients underwent ESD for EGC at six medical centers. The patients were classified into the following two groups based on the lesion size, presence of ulceration and pathological review: an absolute criteria group (n=517) and an expanded criteria group (n=588). Results: The curative resection rates (91.1% vs 91.3%, p=0.896) were similar in the absolute criteria group and the expanded criteria group. The en bloc resection rates (93.4% and 92.3%, respectively; p=0.488) and complete resection rates (98.3% and 97.4%, respectively; p=0.357) did not differ between the groups. The cumulative disease-free survival rates and the overall survival rates were similar between the groups (p=0.778 and p=0.654, respectively). Independent factors for the curative resection of EGC included tumor location (upper vs middle and lower, 2.632 [1.128-6.144] vs 3.497 [1.560-7.842], respectively) and en bloc resection rate 12.576 [7.442-21.250]. Conclusions: The expanded criteria for ESD in cases of EGC is comparable with the widely accepted pre-existing criteria. (Gut Liver, 2015;9:181-187)

Magnetic carbon nanoparticles (MC NPs) are prepared on a multi-gram scale through carbonization of iron-doped polypyrrole nanoparticles (PPy NPs). Three different-sized MC NPs (ca. 40, 60 and 90 nm) are prepared and adopted as dispersing materials for magnetorheological (MR) fluids to investigate the influence of particle size on MR properties. The MC NP-based MR fluids exhibit outstanding MR performances compared to the conventional magnetic carbon material-based fluids. In addition, the MR activities are enhanced with decreasing particle diameter and increasing applied magnetic field strength. Furthermore, anti-sedimentation properties are examined in order to achieve in-depth insight into the effect of the particle size on MR fluids.

We report a novel method for synthesizing highly porous polyaniline (PANI) using carbon nanodots (CNDs) as a nucleating agent and demonstrate their use as counter electrodes (CEs) for dye-sensitized solar cells (DSSCs). CNDs surrounded with aniline act as efficient nuclei in the polymerization reaction. CNDs disrupt undesirable secondary growth reactions leading to the formation of an agglomerated structure, and organize the highly porous PANI structures with a large surface area (43.6 m2 g−1). Moreover, the presence of CNDs in the polymerization mixture facilitates generation of head-to-tail dimers, and enhances the degree of para-coupling in the molecular structure of PANI. As a result of these nucleation effects, the fabricated PANI-CND films exhibit an increased electrical conductivity of ca. 774 S cm−1. When used as a CE in DSSCs, PANI-CND CEs exhibit a superior power conversion efficiency (η = 7.45%) to those of conventional platinum (η = 7.37%) and pristine PANI CEs (η = 5.60%).

This paper examines Korean partitive constructions to investigate the typology of the partitive structure. In Korean, a quantifier precedes the nominal in a non-partitive, but it follows the nominal in a partitive. The relative order between a quantifier and its associated nominal indicates that a quantifier in Korean partitive does not function as a NP adjunct but takes a DP as its argument. I argue that Korean postnominal (floating) quantifier constructions can be interpreted as partitives or pseudo-partitives/quantitatives because a postnominal (floating) quantifier denoting a part-of relation can occur with a kind-denoting DP as well as a definite DP. I also propose that a quantifier denoting a part-of relation is associated with the argument of a verb via composition with a verbal predicate in the floating quantifier construction. This approach can provide an account for several idiosyncratic properties of floating quantifier constructions, which are difficult to capture under the assumption that a floating quantifier construction is derived by moving a quantifier away from its associated nominal. This article is part of the Special Collection: Partitives

Preparation of three-dimensional (3-D) networks has received significant attention as an effective approach for applications involving transport phenomena, such as thermal management materials, and several nanomaterials have been examined as potential building blocks of 3-D networks for the improvement of heat conduction in polymer nanocomposites. For that purpose, nanocarbons such as graphene and graphite nanoplatelets have been spotlighted as suitable filler materials because of their excellent thermal conductivities (ca. 102–103 W·(m·K)−1 along their lateral axes) and morphological merits. However, the implications of morphological features such as the lateral length and thickness of the graphene or graphene-like materials have not yet been identified. In this study, a controlled dissociation of bulk graphite to graphite nanosheets (GNSs) using a low-cost, eco-friendly bead mill process was extensively examined and, when configured in a 3-D framework architecture formation, the size-controlled GNSs demonstrated that the thermal conductivities of a 3-D interconnected framework of GNSs and the corresponding polymer nanocomposite were intimately correlated with the size of the GNSs, thus demonstrating the successful preparation of an efficient thermal management material without highly sophisticated efforts. The capability of controlling the lateral size and thickness of the GNSs as well as the use of a 3-D interconnected framework architecture should greatly assist the commercialization of high-quality graphene-based thermal management materials in a scalable production process.

Highly dispersible graphene oxide (GO) sheets of uniform submicrometer size were successfully fabricated from pristine graphite using a simple mechanochemical process. The GO flake morphology was transformed into a spherical form, and the density was decreased slightly via the ball-milling process. Ball-milled GO can be used as an electrorheological (ER) material because of its small particle size, low conductivity, and outstanding dispersibility in silicone oil. We found that the 2-h ball-milled GO-based ER fluid had the best ER performance (shear stress of 78.5 Pa and 630% ER efficiency), which was double that of the nonmilled GO-based ER fluid. The response time to form a fibrillar structure along the applied electric field direction and the recovery time to the starting level decreased with increasing ball-milling time. Additionally, the retarded settling velocity of isolated GO sheets and the electrostatic repulsion between oxygen functional groups on the GO sheets combined to improve the antisedimentation property. The ability to control the size of graphene sheets is a great opportunity to advance graphene commercialization in a high-quality, scalable production setting.

Highly conductive, transparent, flexible and scalable graphene hybrid thin films with controlled domain size were successfully fabricated via a mechanochemical method, screen printing and pressure-assisted reduction process.

We describe the designed fabrication of magnetically recyclable core–shell Pd nanocatalysts for the efficient oxidation of alcohols under base-free reaction conditions in water. The Pd NPs that are half-partitioned in the polymer matrix can provide not only high catalytic activity but also stabilization of the nanocatalysts under harsh reaction conditions. Furthermore the magnetic separation provides a convenient method for removing and recycling the active Pd nanocatalysts from the reaction mixture. The designed nanocatalysts can be readily synthesized in a large scale and were able to be reused for five consecutive cycles of the oxidation of cycloheptanol. The nanocatalysts present high catalytic activity in other types of catalytic reactions involving Pd NPs such as Suzuki cross-coupling and reduction of nitroarenes.

We report a facile approach for producing reversibly stretchable, optically transparent radio-frequency antennas based on wavy Ag nanowire (NW) networks. The wavy configuration of Ag NWs is obtained by floating the NW networks on the surface of water, followed by compression. Stretchable antennas are prepared by transferring the compressed NW networks onto elastomeric substrates. The resulting antennas show excellent performance under mechanical deformation due to the wavy configuration, which allows the release of stress applied to the NWs and an increase in the contact area between NWs. The antennas formed from the wavy NW networks exhibit a smaller return loss and a higher radiation efficiency when strained than the antennas formed from the straight NW networks, as well as an improved stability in cyclic deformation tests. Moreover, the wavy NW antennas require a relatively small quantity of NWs, which leads to low production costs and provides an optical transparency. These results demonstrate the potential of these wavy Ag NW antennas in applications of wireless communications for wearable systems.

Colonoscopy and polypectomy procedures have effectively reduced the incidence of colorectal cancer. Currently, competence in colonoscopy is an essential part of the education program for gastrointestinal (GI) trainees. However, considerable training is required for the optimal performance of a colonoscopy. This study involved six colonoscopy trainees, three of whom used the cap whereas the others did not. Each trainee managed 100 cases of screening colonoscopy from beginning to end. The cecal intubation success rate, cecal intubation time, polyp detection rate, adenoma detection rate, advanced adenoma detection rate, and adenocarcinoma detection rate were checked. The rate of successful cecal intubation and the cecal intubation time were reviewed every 10 cases. The cecal intubation rate was 80.7 % (242/300) in the cap group and 63.3 % (190/300) in the non-cap group. The average cecal intubation time was 13.7 min in the cap group and 18.7 min in the non-cap group. The statistical analysis of these results suggested that the cap group had a significantly higher success rate (p

Background/Aims Obesity tends to be associated with increased mortality and morbidity in acute pancreatitis. However, in Asian populations, higher morbidity and mortality have been reported in patients with low body mass indexes (BMIs). This study was undertaken to evaluate the relation between obesity and outcome, and to investigate the occurrence of complications by overweightedness in acute pancreatitis. Methods The medical records of 403 patients with acute pancreatitis were reviewed retrospectively, and Ranson's scores, modified Glasgow scores, Acute Physiology and Chronic Health Evaluation (APACHE) II scores and computed tomography severity indexes were calculated. Patients were categorized by BMI for the analysis. Results When compared with normal patients (BMI 18.5 to 22.9), all categories with a BMI ≥23 had an increased risk of developing a severe form of acute pancreatitis (p=0.003) and all categories with a BMI ≥25 significantly predicted severity (p

PURPOSE: A graphene sheet using inkjet printing and a wideband dipole antenna application are provided to minimize the loss of raw material and time. CONSTITUTION: Waterborne graphene oxide nano particle solution is manufactured and is used for conductive ink of inkjet printing. The chemical characteristic of the waterborne graphene oxide nano particle solution is changed in order to form a detailed pattern on a supporting material. The waterborne graphene oxide nano particle solution is injected to a printer head, and an oxide graphene thin film is formed. The supporting material including the oxide graphene thin film is located in a vapor deposition reactor, and an oxidation-reduction reaction is executed. A graphene sheet based broadband dipole antenna electrode is connected to an antenna analysis device, and the performance of the antenna is measured.

This paper provides an examination and analysis of two roughly synonymous aspectual markers in Korean, pelita and malta, that developed from the transitive verbs ‘throw away’ and ‘stop’, respectively. Based on electronic corpora, it is shown that these markers are distributed divergently: malta is strongly preferred to pelita in passive, non-volitional and resistant contexts. The divergent distributions of pelita and malta can be more clearly understood in terms of transitivity. I propose that the transitivity difference of their lexical sources is reflected in constraints on their grammaticalisation and contemporary uses. The low vs. high transitivity of the lexical verbs malta and pelita has persisted in grammaticalisation and brought about differences between their grammaticalised forms. This paper suggests that the gradient notion of transitivity can be used as an explanatory principle that generalises differences between synonymous grammatical words that developed from different lexical verbs.

Highly omnidirectional and frequency controllable carbon/polyaniline (C/PANI)-based, two- (2D) and three-dimensional (3D) monopole antennas were fabricated using screen-printing and a one-step, dimensionally confined hydrothermal strategy, respectively. Solvated C/PANI was synthesized by low-temperature interfacial polymerization, during which strong π–π interactions between graphene and the quinoid rings of PANI resulted in an expanded PANI conformation with enhanced crystallinity and improved mechanical and electrical properties. Compared to antennas composed of pristine carbon or PANI-based 2D monopole structures, 2D monopole antennas composed of this enhanced hybrid material were highly efficient and amenable to high-frequency, omnidirectional electromagnetic waves. The mean frequency of C/PANI fiber-based 3D monopole antennas could be controlled by simply cutting and stretching the antenna. These antennas attained high peak gain (3.60 dBi), high directivity (3.91 dBi) and radiation efficiency (92.12%) relative to 2D monopole antenna. These improvements were attributed the high packing density and aspect ratios of C/PANI fibers and the removal of the flexible substrate. This approach offers a valuable and promising tool for producing highly omnidirectional and frequency-controllable, carbon-based monopole antennas for use in wireless networking communications on industrial, scientific and medical (ISM) bands.

We demonstrate an 80-μm-thick film (which is around 15% of the thickness of the human epidermis), which is a highly sensitive hybrid functional gauge sensor and was fabricated from poly(vinylidene fluoride) (PVDF) and ZnO nanostructures with graphene electrodes. Using this film, we were able to simultaneously measure pressure and temperature in real time. The pressure was monitored from the change in the electrical resistance via the piezoresistance of the material and the temperature was inferred based on the recovery time of the signal. Our thin film system enabled us to detect changes in pressure as small as 10 Pa which is pressure detection limit was 103-fold lower than the minimum level required for artificial skin and to detect temperatures in the range 20–120°C.

Paralabral cyst around hip is reported to be a cause of compression of the major neurovascular structures. Although, arthroscopic cyst and labral debridement is generally accepted as the effective treatment, there is limited literature available regarding treatment options for paralabral cysts in the hip. We present a case of paralabral cyst compressing left common femoral vein in the hip that was treated with sono-guided cyst aspiration followed by arthroscopic labral debridement.

A highly conductive and durable copper (Cu) paste was successfully fabricated via acid treatment and mechanical blending with corrosion inhibitors. A screen-printed Cu pattern was evaluated as a dipole tag-antenna with long term and thermal stability, and structural flexibility.

A high-performance polyvinylidene fluoride (PVDF) based thin film acoustic actuator with chemical vapor deposition (CVD) graphene electrodes was successfully fabricated. Importantly, it showed 60, 19, and 22% enhancement in the bass, middle and treble frequency response, respectively.

Resistive random access memory (ReRAM) has a great potential to be the next-generation non-volatile memory device. However, the random nucleation and growth of conductive filaments (CFs) in ReRAM causes the low reliability in switching behaviors, leading to difficulties in its practical application. This study demonstrates that manipulating electric fields in ReRAM via a structured electrode can provide the controllable formation of CFs. Ag pyramids that have a high-quality tip prepared via the template-stripping method generate highly enhanced electric fields at the tip. Because the tip-enhanced electric fields can facilitate the ionization of Ag atoms and their migration along the electric fields, the nucleation and growth of CFs occurs predominantly at the tip. The CFs in ReRAM are directly observed using electron microscopy and it is confirmed that the CFs are formed only at the tip. The resulting ReRAM exhibits low and reliable SET/RESET voltages (0.48 V ± 0.02 V and 0.15 V ± 0.06 V, respectively). Moreover, its endurance and retention time are highly improved, compared to those devices that are based on conventional geometry. Thus, this approach can encourage creating high-performance ReRAM.

The present invention relates to a method for manufacturing a graphene/polyaniline/polystyrene sulfonate hybrid thin film having uniform surface resistance and an application thereof to a dipole tag antenna. The present invention suggests a possibility as a dipole tag antenna electrode by introducing, to graphite, persulfuric acid potassium which is an oxidizer, a vacuum filtration method, and a superhigh frequency to manufacture multi-layered structure graphene, by adding, in the multi-layered structure graphene, a polyaniline nanofiller which is conductive polymer and polystyrene sulfonate as a compatibilizing agent and a binder to manufacture conductive ink for screen printing, and by forming a graphene/polyaniline/polystyrene sulfonate hybrid thin film on a flexible film using screen printing. According to the present invention, provided are the technologies of manufacturing the graphene/polyaniline/polystyrene sulfonate hybrid thin film having uniform resistance properties, easily forming, on the flexible film, the graphene/polyaniline/polystyrene sulfonate hybrid thin film having desired shape, size, and a uniform thickness using a fine mesh of the screen printing, and producing in bulk the graphene/polyaniline/polystyrene sulfonate hybrid thin film with low costs by using price compatible graphite. Also, the graphene/polyaniline/polystyrene sulfonate hybrid thin film manufactured by the above technologies can maintain high flexibility in case of being folded or bent due to excellent mechanical properties and has antenna properties having high power transmission efficiency in use as an electrode for a dipole tag antenna.

Carbon sponge, an adsorbent with spatially controlled structure is demonstrated for targeting internalized radiocesium and other radionuclides in human body. Three dimensionally ordered macroporous (3DOM) carbons derived from inverse opal replicas of colloidal-crystal template exhibit large surface area and high porosity, resulting in highly efficient adsorbents for radionuclides. It is also possible to enhance binding affinity and selectivity to radionuclide targets by decoration of 3DOM carbon surfaces with Prussian blue (PB) nanoparticles, and synthesized PB nanoparticles reveal low toxicity toward macrophage cells with potential advantages over oral administration. It is noteworthy that the maximum (133)Cs adsorption capacity of PB-decorated 3DOM carbons is 40.07 mmol g(-1) which is ca. 30 and 200 times higher than that of commercialized medicine Radiogardase(®) and bulk PB, respectively. Further, adsorption kinetics study indicates that the PB-decorated 3DOM carbons have the homogenous surface for (133)Cs ion adsorption and all sites have equal adsorption energies in terms of ion exchange between the cyano groups of the PB-decorated 3DOM carbons and radionuclides. As a concept of the oral-administrable "carbon sponge", the PB-decorated 3DOM carbons offer useful implications in the separation science of radioactive materials and important insight for designing novel materials for treatment of patients or suspected internal contamination with radioactive materials.

Radiofrequency ablation (RFA) is performed as an alternative to surgical resection for primary or secondary liver malignancies. Although RFA can be performed safely in most patients, early and late complications related to mechanical or thermal damage occur in 8-9.5% cases. Hemocholecyst, which refers to hemorrhage of the gallbladder, has been reported with primary gallbladder disease or as a secondary event associated with hemobilia. Hemobilia, defined as hemorrhage in the biliary tract and most commonly associated with accidental or iatrogenic trauma, is a rare complication of RFA. Here we report a case of hemocholecyst associated with hemobilia after RFA for hepatocellular carcinoma that was successfully managed by laparoscopic cholecystectomy.