Calf Circumference as an Indicator for Cystatin C Testing in Hospitalized Elderly Male Patients for Detecting Hidden Renal Impairment.

Serum creatinine is used to measure the estimated glomerular filtration rate (eGFR); however, it is influenced by muscle mass and may therefore overestimate renal function in patients with sarcopenia. We examined calf circumference (CC) as a convenient muscle mass evaluation tool that can potentially indicate the need to test for cystatin C instead of creatinine in elderly inpatients. We retrospectively reviewed the electronic health record of 271 inpatients aged 65 or over. CC was determined by measuring the thickest part of the nondominant calf. eGFRcys and eGFRcr were calculated using cystatin C and creatinine levels, respectively. We evaluated optimum CC cutoff values using the eGFRcys/eGFRcr ratio for detecting hidden renal impairment (HRI, defined as eGFRcr ≥ 60 mL/min/1.73 m2 but eGFRcys < 60 mL/min/1.73 m2). CC showed a significant positive correlation with the eGFRcys/eGFRcr ratio in both sexes. The areas under the receiver operating characteristic curve were 0.725 and 0.681 for males and females, respectively. CC cutoffs with a sensitivity or specificity of 90% or 95% might be used to detect HRI in males. In conclusion, utilizing the optimum cutoff, CC could be a cost-effective screening tool for detecting HRI in elderly male patients using cystatin C as an add-on test.

Mold-Free Manufacturing of Highly Sensitive and Fast-Response Pressure Sensors Through High-Resolution 3D Printing and Conformal Oxidative Chemical Vapor Deposition Polymers.

A new manufacturing paradigm is showcased to exclude conventional mold-dependent manufacturing of pressure sensors, which typically requires a series of complex and expensive patterning processes. This mold-free manufacturing leverages high-resolution 3D-printed multiscale microstructures as the substrate and a gas-phase conformal polymer coating technique to complete the mold-free sensing platform. The array of dome and spike structures with a controlled spike density of a 3D-printed substrate ensures a large contact surface with pressures applied and extended linearity in a wider pressure range. For uniform coating of sensing elements on the microstructured surface, oxidative chemical vapor deposition is employed to deposit a highly conformal and conductive sensing element, poly(3,4-ethylenedioxythiophene) at low temperatures (<60 °C). The fabricated pressure sensor reacts sensitively to various ranges of pressures (up to 185 kPa-1 ) depending on the density of the multiscale features and shows an ultrafast response time (≈36 µs). The mechanism investigations through the finite element analysis identify the effect of the multiscale structure on the figure-of-merit sensing performance. These unique findings are expected to be of significant relevance to technology that requires higher sensing capability, scalability, and facile adjustment of a sensor geometry in a cost-effective manufacturing manner.

Recent achievements toward the development of Ni-based layered oxide cathodes for fast-charging Li-ion batteries.

The driving mileage of electric vehicles (EVs) has been substantially improved in recent years with the adoption of Ni-based layered oxide materials as the battery cathode. The average charging period of EVs is still time-consuming, compared with the short refueling time of an internal combustion engine vehicle. With the guidance from the United States Department of Energy, the charging time of refilling 60% of the battery capacity should be less than 6 min for EVs, indicating that the corresponding charging rate for the cathode materials is to be greater than 6C. However, the sluggish kinetic conditions and insufficient thermal stability of the Ni-based layered oxide materials hinder further application in fast-charging operations. Most of the recent review articles regarding Ni-based layered oxide materials as cathodes for lithium-ion batteries (LIBs) only touch degradation mechanisms under slow charging conditions. Of note, the fading mechanisms of the cathode materials for fast-charging, of which the importance abruptly increases due to the development of electric vehicles, may be significantly different from those of slow charging conditions. There are a few review articles regarding fast-charging; however, their perspectives are limited mostly to battery thermal management simulations, lacking experimental validations such as microscale structure degradations of Ni-based layered oxide cathode materials. In this review, a general and fundamental definition of fast-charging is discussed at first, and then we summarize the rate capability required in EVs and the electrochemical and kinetic properties of Ni-based layered oxide cathode materials. Next, the degradation mechanisms of LIBs leveraging Ni-based cathodes under fast-charging operation are systematically discussed from the electrode scale to the particle scale and finally the atom scale (lattice oxygen-level investigation). Then, various strategies to achieve higher rate capability, such as optimizing the synthesis process of cathode particles, fabricating single-crystalline particles, employing electrolyte additives, doping foreign ions, coating protective layers, and engineering the cathode architecture, are detailed. All these strategies need to be considered to enhance the electrochemical performance of Ni-based oxide cathode materials under fast-charging conditions.

Multimodal Encapsulation to Selectively Permeate Hydrogen and Engineer Channel Conduction for p-Type SnOx Thin-Film Transistor Applications.

It has been challenging to synthesize p-type SnOx (1 < x < 2) and engineer the electrical properties such as carrier density and mobility due to the narrow processing window and the localized oxygen 2p orbitals near the valence band. Herein, we report on the multifunctional encapsulation of p-SnOx to limit the surface adsorption of oxygen and selectively permeate hydrogen into the p-SnOx channel for thin-film transistor (TFT) applications. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements identified that ultrathin SiO2 as a multifunctional encapsulation layer effectively suppressed the oxygen adsorption on the back channel surface of p-SnOx and selectively diffused hydrogen across the entire thickness of the channel. Encapsulated p-SnOx-based TFTs demonstrated much enhanced channel conductance modulation in response to the gate bias applied, featuring higher on-state current and lower off-state current (on/off ratio > 103), field effect mobility of 3.41 cm2/(V s), and threshold voltages of ∼5-10 V. The fabricated devices show minimal deviations as small as ±6% in the TFT performance parameters, which demonstrates good reproducibility of the fabrication process. The relevance between the TFT performance and the effects of hydrogen permeation is discussed in regard to the intrinsic and extrinsic doping mechanisms. Density functional theory calculations reveal that hydrogen-related impurity complexes are in charge of the enhanced channel conductance with gate biases, which further supports the selective permeation of hydrogen through a thin SiO2 encapsulation.

Association of Tim-3/Gal-9 Axis with NLRC4 Inflammasome in Glioma Malignancy: Tim-3/Gal-9 Induce the NLRC4 Inflammasome.

Tim-3/Gal-9 and the NLRC4 inflammasome contribute to glioma progression. However, the underlying mechanisms involved are unclear. Here, we observed that Tim-3/Gal-9 expression increased with glioma malignancy and found that Tim-3/Gal-9 regulate NLRC4 inflammasome formation and activation. Tim-3/Gal-9 and NLRC4 inflammasome-related molecule expression levels increased with WHO glioma grade, and this association was correlated with low survival. We investigated NLRC4 inflammasome formation by genetically regulating Tim-3 and its ligand Gal-9. Tim-3/Gal-9 regulation was positively correlated with the NLRC4 inflammasome, NLRC4, and caspase-1 expression. Tim-3/Gal-9 did not trigger IL-1ß secretion but were strongly positively correlated with caspase-1 activity as they induced programmed cell death in glioma cells. A protein-protein interaction analysis revealed that the FYN-JAK1-ZNF384 pathways are bridges in NLRC4 inflammasome regulation by Tim-3/Gal-9. The present study showed that Tim-3/Gal-9 are associated with poor prognosis in glioma patients and induce NLRC4 inflammasome formation and activation. We proposed that a Tim-3/Gal-9 blockade could be beneficial in glioma therapy as it would reduce the inflammatory microenvironment by downregulating the NLRC4 inflammasome.

Layer-resolved release of epitaxial layers in III-V heterostructure via a buffer-free mechanical separation technique.

Layer-release techniques for producing freestanding III-V epitaxial layers have been actively developed for heterointegration of single-crystalline compound semiconductors with Si platforms. However, for the release of target epitaxial layers from III-V heterostructures, it is required to embed a mechanically or chemically weak sacrificial buffer beneath the target layers. This requirement severely limits the scope of processable materials and their epi-structures and makes the growth and layer-release process complicated. Here, we report that epitaxial layers in commonly used III-V heterostructures can be precisely released with an atomic-scale surface flatness via a buffer-free separation technique. This result shows that heteroepitaxial interfaces of a normal lattice-matched III-V heterostructure can be mechanically separated without a sacrificial buffer and the target interface for separation can be selectively determined by adjusting process conditions. This technique of selective release of epitaxial layers in III-V heterostructures will provide high fabrication flexibility in compound semiconductor technology.

Simultaneous Extraction of the Grain Size, Single-Crystalline Grain Sheet Resistance, and Grain Boundary Resistivity of Polycrystalline Monolayer Graphene.

The electrical properties of polycrystalline graphene grown by chemical vapor deposition (CVD) are determined by grain-related parameters-average grain size, single-crystalline grain sheet resistance, and grain boundary (GB) resistivity. However, extracting these parameters still remains challenging because of the difficulty in observing graphene GBs and decoupling the grain sheet resistance and GB resistivity. In this work, we developed an electrical characterization method that can extract the average grain size, single-crystalline grain sheet resistance, and GB resistivity simultaneously. We observed that the material property, graphene sheet resistance, could depend on the device dimension and developed an analytical resistance model based on the cumulative distribution function of the gamma distribution, explaining the effect of the GB density and distribution in the graphene channel. We applied this model to CVD-grown monolayer graphene by characterizing transmission-line model patterns and simultaneously extracted the average grain size (~5.95 µm), single-crystalline grain sheet resistance (~321 Ω/sq), and GB resistivity (~18.16 kΩ-µm) of the CVD-graphene layer. The extracted values agreed well with those obtained from scanning electron microscopy images of ultraviolet/ozone-treated GBs and the electrical characterization of graphene devices with sub-micrometer channel lengths.

Clinical Significance of Glycolytic Metabolic Activity in Hepatocellular Carcinoma.

High metabolic activity is a hallmark of cancers, including hepatocellular carcinoma (HCC). However, the molecular features of HCC with high metabolic activity contributing to clinical outcomes and the therapeutic implications of these characteristics are poorly understood. We aimed to define the features of HCC with high metabolic activity and uncover its association with response to current therapies. By integrating gene expression data from mouse liver tissues and tumor tissues from HCC patients (n = 1038), we uncovered three metabolically distinct HCC subtypes that differ in clinical outcomes and underlying molecular biology. The high metabolic subtype is characterized by poor survival, the strongest stem cell signature, high genomic instability, activation of EPCAM and SALL4, and low potential for benefitting from immunotherapy. Interestingly, immune cell analysis showed that regulatory T cells (Tregs) are highly enriched in high metabolic HCC tumors, suggesting that high metabolic activity of cancer cells may trigger activation or infiltration of Tregs, leading to cancer cells' evasion of anti-cancer immune cells. In summary, we identified clinically and metabolically distinct subtypes of HCC, potential biomarkers associated with these subtypes, and a potential mechanism of metabolism-mediated immune evasion by HCC cells.

High-Performance Oxide-Based p-n Heterojunctions Integrating p-SnOx and n-InGaZnO.

The fabrication of oxide-based p-n heterojunctions that exhibit high rectification performance has been difficult to realize using standard manufacturing techniques that feature mild vacuum requirements, low thermal budget processing, and scalability. Critical bottlenecks in the fabrication of these heterojunctions include the narrow processing window of p-type oxides and the charge-blocking performance across the metallurgical junction required for achieving low reverse current and hence high rectification behavior. The overarching goal of the present study is to demonstrate a simple processing route to fabricate oxide-based p-n heterojunctions that demonstrate high on/off rectification behavior, a low saturation current, and a small turn-on voltage. For this study, room-temperature sputter-deposited p-SnOx and n-InGaZnO (IGZO) films were chosen. SnOx is a promising p-type oxide material due to its monocationic system that limits complexities related to processing and properties, compared to other multicationic oxide materials. For the n-type oxide, IGZO is selected due to the knowledge that postprocessing annealing critically reduces the defect and trap densities in IGZO to ensure minimal interfacial recombination and high charge-blocking performance in the heterojunctions. The resulting oxide p-n heterojunction exhibits a high rectification ratio greater than 103 at ±3 V, a low saturation current of ∼2 × 10-10 A, and a small turn-on voltage of ∼0.5 V. In addition, the demonstrated oxide p-n heterojunctions exhibit excellent stability over time in air due to the p-SnOx with completed reaction annealing in air and the reduced trap density in n-IGZO.

Binder-free printed PEDOT wearable sensors on everyday fabrics using oxidative chemical vapor deposition.

Polymeric sensors on fabrics have vast potential toward the development of versatile applications, particularly when the ready-made wearable or fabric can be directly coated. However, traditional coating approaches, such as solution-based methods, have limitations in achieving uniform and thin films because of the poor surface wettability of fabrics. Herein, to realize a uniform poly(3,4-ethylenedioxythiophene) (PEDOT) layer on various everyday fabrics, we use oxidative chemical vapor deposition (oCVD). The oCVD technique is a unique method capable of forming patterned polymer films with controllable thicknesses while maintaining the inherent advantages of fabrics, such as exceptional mechanical stability and breathability. Utilizing the superior characteristics of oCVD PEDOT, we succeed in fabricating blood pressure­ and respiratory rate­monitoring sensors by directly depositing and patterning PEDOT on commercially available disposable gloves and masks, respectively. Those results are expected to pave efficient and facile ways for skin-compatible and affordable sensors for personal health care monitoring.

Midwavelength Infrared p-n Heterojunction Diodes Based on Intraband Colloidal Quantum Dots.

As an emerging member of the colloidal semiconductor quantum dot materials family, intraband quantum dots are being extensively studied for thermal infrared sensing applications. High-performance detectors can be realized using a traditional p-n junction device design; however, the heavily doped nature of intraband quantum dots presents a new challenge in realizing diode devices. In this work, we utilize a trait uniquely available in a colloidal quantum dot material system to overcome this challenge: the ability to blend two different types of quantum dots to control the electrical property of the resulting film. We report on the preparation of binary mixture films containing midwavelength infrared Ag2Se intraband quantum dots and the fabrication of p-n heterojunction diodes with strong rectifying characteristics. The peak specific detectivity at 4.5 µm was measured to be 107 Jones at room temperature, which is an orders of magnitude improvement compared to the previous generation of intraband quantum dot detectors.

Risk factors of incisional hernia after single-incision cholecystectomy and safety of barbed suture material for wound closure.

Purpose: Single-incision cholecystectomy is a surgical method that offers comparable results to conventional laparoscopic cholecystectomy. However, a high risk of postoperative incisional hernia is an issue in single-incision cholecystectomy. This study evaluated the risk factors and incidences of incisional hernia after single-incision cholecystectomy and the advantage issue of using barbed suture material during wound closures. Methods: A total of 1,111 patients underwent laparoscopic or robotic single-incision cholecystectomy between March 2014 and February 2020 at our institution at CHA Bundang Medical Center. During this period, there were 693 patients who underwent wound closure with monofilament suture material (Monosyn 2-0; B. Braun) and the other 418 patients used barbed suture material (Stratafix 2-0; Ethicon). Results: The two patient groups were comparable in age, body mass index, and diagnosis. The total incidence of incisional hernia after single-incision cholecystectomy was 0.5% (five cases). All patients who developed incisional hernia were in the monofilament suture material group (0.7% vs. 0%, p = 0.021). The influence of predictive and possible risk factors on incisional hernia rate was analyzed. Among these factors, only old age was an independent predictive risk factor of incisional hernia. Conclusion: Our study showed a low incidence of incisional hernia, all of which occurred in the monofilament suture material group. If technically appropriate, single-incision cholecystectomy does not appear to present a high incidence of hernia. Barbed suture material can be safely applied in wound closure showing comparable incisional hernia incidence to monofilament suture material.

Pseudo wastewater treatment by combining adsorption and phytoaccumulation on the Acrostichum aureum Linn. plant/activated carbon system.

In this study, the pseudo wastewater containing Zn, Fe, Cu ions was clean-up by a combination of physical adsorption onto activated carbon medium and phytoaccumulation using Acrostichum aureum Linn. plants. The adsorption capability of the activated carbon for the Fe, Cu, and Zn ions was 3.05, 3.72, and 2.85 mg·g - 1, respectively, at the saturation. The phytoaccumulation performance was proved by analyzing the individual residual ash collected after pyrolysis up to 1000 °C of the leaf, stem, and root of the plants. Thermal analyses of thermogravimetry data showed that the weight of the residual ash of the phytoremediated leaf, stem, and root of the plants was 37.0, 19.0, and 65.7 wt.%, respectively. Energy-dispersive X - ray spectroscopy determined the amount of Fe element in the residual ash of phytoremediated root is 7.05 wt.%, while that of the initial root is 1.18 wt.%. Conclusively, it can be proved that combining physical and biological processes is feasible to treat wastewater containing metal ions.

Nucleation promoted synthesis of large-area ReS2 film for high-speed photodetectors.

Rhenium disulfide (ReS2) is a transition metal dichalcogenide with a layer-independent direct bandgap. Notably, the weak interlayer coupling owing to its T-phase structure enables multi-layer ReS2 to behave similarly to decoupled monolayers. This inherent characteristic makes continuous multilayer ReS2 film a unique platform for large-area electronic applications. To date, the bulk of work on ReS2 has been conducted using mechanically exfoliated samples or small size flakes (<1 mm2) with no potential for large-scale electronics. A chemical vapor deposition (CVD) synthesis of a large area, continuous ReS2 film directly on a SiO2 substrate is also known to be more challenging compared with that of other 2D materials, such as MoS2 and WS2. This is partly due to its tendency to grow into discrete dendritic structures. In this study, a large-area (>1 cm2), continuous multilayer ReS2 film is directly synthesized on a SiO2 substrate without any transfer process. The polycrystalline ReS2 film synthesized by this method exhibits one of the fastest photoresponse speeds (0.03 s rise time and 0.025 s decay time) among the reported CVD films. The photoresponsivity R λ was also the highest among large-area CVD films. The synthesis method for a continuous multilayer ReS2 film is amenable to large-scale integration and will pave the way for practical optoelectronic applications based on 2D layered materials.

Graphene-Edge Electrode on a Cu-Based Chalcogenide Selector for 3D Vertical Memristor Cells.

Resistive memristors are considered to be key components in the hardware implementation of complex neuromorphic networks because of their simplicity, compactness, and manageable power dissipation. However, breakthroughs with respect to both the selector material technology and the bit-cost-effective three-dimensional (3D) device architecture are necessary to provide sufficient device density while maintaining the advantages of a two-terminal device. Despite substantial progress in the scaling of the memristor devices, the scaling potential of the selector materials remains unclear. A majority of the selector materials are unlikely to form conductive filaments, and the effect of the highly concentrated electrical fields on such materials is not well understood. In this study, the atomically thin graphene edge in a 3D vertical memory architecture is utilized to study the effect of highly focused electrical fields on a CuGeS chalcogenide selector layer. We demonstrate that additional interface resistance can improve the nonlinearity and reduce leakage current by almost three orders of magnitude; however, even a relatively low Cu+ ion density can adversely affect leakage because of the highly asymmetric electrode configuration. This study presents a meaningful step toward understanding the characteristics of mobile ions in solid chalcogenide electrolytes and the potential for ultrascaled selector devices.

Effects of membrane thickness on the performance of ionic polymer-metal composite actuators.

In this study, we report the effects of Nafion thickness on the performance of ionic polymer-metal composite (IPMC) actuators. We analyzed the actuation properties of the IPMC actuators, such as displacement and tip force, under external voltage, as a function of their thickness. In order to understand the relationship between thickness and actuation properties, we developed a semi-quantitative model of voltage induced ionic diffusion and its contribution to bending of the Nafion cantilever. Furthermore, we investigated the mechanical properties of the Nafion membranes at sub-micro scale as well as bulk scale, using atomic force microscopy (AFM) and tensile test. The results of the two methods indicated opposite trends of elastic modulus and crystallinity as a function of thickness. We hypothesized that the hot-pressed Nafion was composed of three layers with different crystallinity. Our results suggest that for a high performance IPMC actuator, we need better control of the annealing temperature gradient.

High electrical conductivity and carrier mobility in oCVD PEDOT thin films by engineered crystallization and acid treatment.

Air-stable, lightweight, and electrically conductive polymers are highly desired as the electrodes for next-generation electronic devices. However, the low electrical conductivity and low carrier mobility of polymers are the key bottlenecks that limit their adoption. We demonstrate that the key to addressing these limitations is to molecularly engineer the crystallization and morphology of polymers. We use oxidative chemical vapor deposition (oCVD) and hydrobromic acid treatment as an effective tool to achieve such engineering for conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). We demonstrate PEDOT thin films with a record-high electrical conductivity of 6259 S/cm and a remarkably high carrier mobility of 18.45 cm2 V-1 s-1 by inducing a crystallite-configuration transition using oCVD. Subsequent theoretical modeling reveals a metallic nature and an effective reduction of the carrier transport energy barrier between crystallized domains in these thin films. To validate this metallic nature, we successfully fabricate PEDOT-Si Schottky diode arrays operating at 13.56 MHz for radio frequency identification (RFID) readers, demonstrating wafer-scale fabrication compatible with conventional complementary metal-oxide semiconductor (CMOS) technology. The oCVD PEDOT thin films with ultrahigh electrical conductivity and high carrier mobility show great promise for novel high-speed organic electronics with low energy consumption and better charge carrier transport.

Obtaining a Low and Wide Atomic Layer Deposition Window (150-275 °C) for In2 O3 Films Using an InIII Amidinate and H2 O.

Indium oxide is a major component of many technologically important thin films, most notably the transparent conductor indium tin oxide (ITO). Despite being pyrophoric, homoleptic indium(III) alkyls do not allow atomic layer deposition (ALD) of In2 O3 using water as a co-precursor at substrate temperatures below 200 °C. Several alternative indium sources have been developed, but none allows ALD at lower temperatures except in the presence of oxidants such as O2 or O3 , which are not compatible with some substrates or alloying processes. We have synthesized a new indium precursor, tris(N,N'-diisopropylformamidinato)indium(III), compound 1, which allows ALD of pure, carbon-free In2 O3 films using H2 O as the only co-reactant, on substrates in the temperature range 150-275 °C. In contrast, replacing just the H of the anionic iPrNC(H)NiPr ligand with a methyl group (affording the known tris(N,N'-diisopropylacetamidinato)indium(III), compound 2) results in a considerably higher and narrower ALD window in the analogous reaction with H2 O (225-300 °C). Kinetic studies demonstrate that a higher rate of surface reactions in both parts of the ALD cycle gives rise to this difference in the ALD windows.

Simultaneous enhancement of upconversion and downshifting luminescence via plasmonic structure.

We describe a metal nanodisk-insulator-metal (MIM) structure that enhances lanthanide-based upconversion (UC) and downshifting (DS) simultaneously. The structure was fabricated using a nanotransfer printing method that facilitates large-area applications of nanostructures for optoelectronic devices. The proposed MIM structure is a promising way to harness the entire solar spectrum by converting both ultraviolet and near-infrared to visible light concurrently through resonant-mode excitation. The overall photoluminescence enhancements of the UC and DS were 174- and 29-fold, respectively.

Effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone and N-terminal telopeptide in the postmenopausal women.

Menopause is characterized by rapid decreases in bone mineral density, aerobic fitness, muscle strength, and balance. In the present study, we investigated the effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone (FSH) and N-terminal telopeptide (NTX) in the postmenopausal women. Subjects were consisted of 20 postmenopausal women, who had not menstruated for at least 1 yr and had follicle-stimulating hormone levels > 35 mIU/L, estradiol levels< 40 pg/mL. The subjects were randomly divided into two groups: control group (n= 10), new sports tennis type exercise group (n= 10). New sports tennis type exercise was consisted of warm up (10 min), new sports tennis type exercise (40 min), cool down (10 min) 3 days a per week for 12 weeks. The aerobic capacities were increased by 12 weeks new sports tennis type exercise. New sports tennis type exercise significantly increased FSH and NTx levels, indicating biochemical markers of bone formation and resorption. These findings indicate that 12 weeks of new sports tennis type exercise can be effective in prevention of bone loss and enhancement of aerobic capacity in postmenopausal women.