Nonalcoholic fatty liver disease(NAFLD)is a frequent cause of chronic liver diseases,ranging from simple steatosis to nonalcoholic steatohepatitis(NASH)-related liver cirrhosis.Although liver biopsy ...is still the gold standard for the diagnosis of NAFLD,especially for the diagnosis of NASH,imaging methods have been increasingly accepted as noninvasive alternatives to liver biopsy.Ultrasonography is a well-established and costeffective imaging technique for the diagnosis of hepatic steatosis,especially for screening a large population at risk of NAFLD.Ultrasonography has a reasonable accuracy in detecting moderate-to-severe hepatic steatosis although it is less accurate for detecting mild hepatic steatosis,operator-dependent,and rather qualitative.Computed tomography is not appropriate for general population assessment of hepatic steatosis given its inaccuracy in detecting mild hepatic steatosis and potential radiation hazard.However,computed tomography may be effective in specific clinical situations,such as evaluation of donor candidates for hepatic transplantation.Magnetic resonance spectroscopy and magnetic resonance imaging are now regarded as the most accurate practical methods of measuring liver fat in clinical practice,especially for longitudinal followup of patients with NAFLD.Ultrasound elastography and magnetic resonance elastography are increasingly used to evaluate the degree of liver fibrosis in patients with NAFLD and to differentiate NASH from simple steatosis.This article will review current imaging methods used to evaluate hepatic steatosis,including the diagnostic accuracy,limitations,and practical applicability of each method.It will also briefly describe the potential role of elastography techniques in the evaluation of patients with NAFLD.
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•Microplastics are ubiquitous in the waters and fish of the Han River.•Tributaries play an important role as sources of microplastic into the mainstream.•Abundance of microplastics in ...Han River was influenced by depth.•Most microplastics in the Han River and its tributaries were fragments.•Microplastics in fish was influenced by habitats rather than feeding habit.
Microplastic pollution has been paid attention due to the possibly global threat to human health and ecosystem in recent years. In this study, we investigated the distribution of microplastics in the Han River and its tributaries, South Korea, and in six species of inhabiting fish, namely carp (C. carpio), crucian carp (C. cuvieri), bluegill (L. macrochirus), bass (M. salmoides), catfish (S. asotus), and snakehead (C. argus). We found that the concentration of microplastics in the surface waters (0 m) was 0–42.9 particles/m3 (mean: 7.0 ± 12.9 particles/m3) compared to 20.0–180.0 particles/m3 (mean: 102.0 ± 50.3 particles/m3) at a depth of 2 m. Concentrations in the river tributaries ranged from 1.2 to 234.5 particles/m3 (mean: 91.1 ± 72.3 particles/m3). The most common types the plastic identified were polyethylene (PE), silicone, and polystyrene, while polytetrafluoroethylene (PTFE), polyethylene, and polyester dominated in the tributaries. With respect to shape, >73% of the recovered microplastics were fragments and the rest were fibers in the water. We also measured the concentration of microplastics in the intestines of fish, which ranged from 4 to 48 particles/fish (mean: 22.0 ± 16.0 particles/fish). The most common types of plastic found in the sampled fish were polytetrafluoroethylene (PFTE), polyethylene (PE), and rayon, and >94% of all the microplastic found in fish was in the form of fragments with the remainder being fibers. The concentrations of microplastic in the gills of fish ranged from 1 to 16 particles/fish (mean: 8.3 ± 6.0 particles/fish). In contrast, no microplastic was found in the flesh of the sampled fish. Our results imply that the ingestion of microplastics by fish is more closely related to habitat rather than feeding habits.
Herein, we describe simple, fast and reproducible halide ion exchange reactions in CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) at room temperature. Through the simple adjustment of the halide ion ...concentration, the photoluminescence of these NCs can be tuned over the entire visible region (425-655 nm). Photodetector devices based on entirely inorganic CsPbI3 NCs are demonstrated for the first time. The photodetectors exhibited a good on/off photocurrent ratio of 10(5).
Developing high‐energy‐density electrodes for lithium ion batteries (LIBs) is of primary importance to meet the challenges in electronics and automobile industries in the near future. Conversion ...reaction‐based transition metal oxides are attractive candidates for LIB anodes because of their high theoretical capacities. This review summarizes recent advances on the development of nanostructured transition metal oxides for use in lithium ion battery anodes based on conversion reactions. The oxide materials covered in this review include oxides of iron, manganese, cobalt, copper, nickel, molybdenum, zinc, ruthenium, chromium, and tungsten, and mixed metal oxides. Various kinds of nanostructured materials including nanowires, nanosheets, hollow structures, porous structures, and oxide/carbon nanocomposites are discussed in terms of their LIB anode applications.
Conversion reaction‐based oxides are considered promising anode materials to replace graphite due to their high theoretical capacity. This review summarizes recent advances in the development of nanostructured transition metal oxides for use in lithium ion battery anodes based on conversion reactions. Moreover, some important aspects and future directions for designing high‐performance anodes are discussed.
As part of increased efforts to develop wearable healthcare devices for monitoring and managing physiological and metabolic information, stretchable electrochemical sweat sensors have been ...investigated. In this study, we report on the fabrication of a stretchable and skin-attachable electrochemical sensor for detecting glucose and pH in sweat. A patterned stretchable electrode was fabricated via layer-by-layer deposition of carbon nanotubes (CNTs) on top of patterned Au nanosheets (AuNS) prepared by filtration onto stretchable substrate. For the detection of glucose and pH, CoWO4/CNT and polyaniline/CNT nanocomposites were coated onto the CNT–AuNS electrodes, respectively. A reference electrode was prepared via chlorination of silver nanowires. Encapsulation of the stretchable sensor with sticky silbione led to a skin-attachable sweat sensor. Our sensor showed high performance with sensitivities of 10.89 μA mM–1 cm–2 and 71.44 mV pH–1 for glucose and pH, respectively, with mechanical stability up to 30% stretching and air stability for 10 days. The sensor also showed good adhesion even to wet skin, allowing the detection of glucose and pH in sweat from running while being attached onto the skin. This work suggests the application of our stretchable and skin-attachable electrochemical sensor to health management as a high-performance healthcare wearable device.
Assessment of functional independence and residual disability is very important for measuring treatment outcome after stroke. The modified Rankin Scale (mRS) and the modified Barthel Index (MBI) are ...commonly used scales to measure disability or dependence in activities of daily living (ADL) of stroke survivors. Lack of consensus regarding MBI score categories has caused confusion in interpreting stroke outcomes. The purpose of this study was to identify the optimal corresponding MBI and modified Rankin scale (mRS) grades for categorization of MBI. The Korean versions of the MBI (K-MBI) and mRS were collected from 5,759 stroke patients at 3 months after onset of stroke. The sensitivity and specificity were calculated at K-MBI score cutoffs for each mRS grade to obtain optimally corresponding K-MBI scores and mRS grades. We also plotted receiver operating characteristic (ROC) curves of sensitivity and specificity and determined the area under the curve (AUC). The K-MBI cutoff points with the highest sum of sensitivity and specificity were 100 (sensitivity 0.940; specificity 0.612), 98 (sensitivity 0.904; specificity 0.838), 94 (sensitivity 0.885; specificity 0.937), 78 (sensitivity 0.946; specificity, 0.973), and 55 (sensitivity 937; specificity 0.986) for mRS grades 0, 1, 2, 3, and 4, respectively. From this result, the K-MBI cutoff score range for each mRS grade can be obtained. For mRS grade 0, the K-MBI cutoff score is 100, indicating no associated score range. For mRS grades 1, 2, 3, 4, and 5, the K-MBI score ranges is from 99 to 98, 97 to 94, 93 to 78, 77 to 55, and under 54, respectively.The AUC for the ROC curve was 0.791 for mRS grade 0, 0.919 for mRS grade 1, 0.970 for mRS grade 2, 0.0 for mRS grade 3, and 0.991 for mRS grade 4. The K-MBI cutoff score ranges for representing mRS grades were variable; mRS grades 0, 1, and 2 had narrow K-MBI score ranges, while mRS grades 3, 4, and 5 exhibited broad K-MBI score ranges. mRS grade seemed to sensitively differentiate mild residual disability of stroke survivors, whereas K-MBI provided more specific information of the functional status of stroke survivors with moderate to severe residual impairment.
Design and fabrication of a 1-MW inductive power transfer (IPT) system that supplies power to the vehicle in real time without any battery charge is proposed for a high-speed train. The IPT system ...consists of a 1-MW resonant inverter, a 128-m transmitter, four pickups, including rectifiers, and a wireless feedback network to maintain a constant output voltage of the pickups. The operating frequency of the system is 60 kHz to achieve efficient power transfer with a large air gap. The measured efficiency of the IPT system at the 818-kW output power of the pickups for the 5-cm air gap is 82.7%. The electromagnetic field and the induced voltage at the rail are also measured for safety evaluation. The fabricated IPT system was adapted to the high-speed train, and the train successfully accelerates to a speed of 10 km/h according to startup procedures.
The hard X-ray free-electron laser at the Pohang Accelerator Laboratory (PAL-XFEL) in the Republic of Korea achieved saturation of a 0.144 nm free-electron laser beam on 27 November 2016, making it ...the third hard X-ray free-electron laser in the world, following the demonstrations of the Linac Coherent Light Source (LCLS) and the SPring-8 Angstrom Compact Free Electron Laser (SACLA). The use of electron-beam-based alignment incorporating undulator radiation spectrum analysis has allowed reliable operation of PAL-XFEL with unprecedented temporal stability and dispersion-free orbits. In particular, a timing jitter of just 20 fs for the free-electron laser photon beam is consistently achieved due to the use of a state-of-the-art design of the electron linear accelerator and electron-beam-based alignment. The low timing jitter of the electron beam makes it possible to observe Bi(111) phonon dynamics without the need for timing-jitter correction, indicating that PAL-XFEL will be an extremely useful tool for hard X-ray time-resolved experiments. The Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) in South Korea has now entered operation with a timing jitter of just 20 fs.
Mechanistic understanding of biochemical reactions requires structural and kinetic characterization of the underlying chemical processes. However, no single experimental technique can provide this ...information in a broadly applicable manner and thus structural studies of static macromolecules are often complemented by biophysical analysis. Moreover, the common strategy of utilizing mutants or crosslinking probes to stabilize intermediates is prone to trapping off-pathway artefacts and precludes determining the order of molecular events. Here we report a time-resolved sample preparation method for cryo-electron microscopy (trEM) using a modular microfluidic device, featuring a 3D-mixing unit and variable delay lines that enables automated, fast, and blot-free sample vitrification. This approach not only preserves high-resolution structural detail but also substantially improves sample integrity and protein distribution across the vitreous ice. We validate the method by visualising reaction intermediates of early RecA filament growth across three orders of magnitude on sub-second timescales. The trEM method reported here is versatile, reproducible, and readily adaptable to a broad spectrum of fundamental questions in biology.
Nanoparticles have been extensively used to deliver therapeutic drugs to tumor tissues through the extravasation of a leaky vessel via enhanced permeation and retention effect (EPR, passive ...targeting) or targeted interaction of tumor-specific ligands (active targeting). However, the therapeutic efficacy of drug-loaded nanoparticles is hampered by its heterogeneous distribution owing to limited penetration in tumor tissue. Inspired by the fact that cancer cells can recruit inflammatory immune cells to support their survival, we developed a click reaction-assisted immune cell targeting (CRAIT) strategy to deliver drug-loaded nanoparticles deep into the avascular regions of the tumor. Immune cell-targeting CD11b antibodies are modified with trans-cyclooctene to enable bioorthogonal click chemistry with mesoporous silica nanoparticles functionalized with tetrazines (MSNs-Tz). Sequential injection of modified antibodies and MSNs-Tz at intervals of 24 h results in targeted conjugation of the nanoparticles onto CD11b+ myeloid cells, which serve as active vectors into tumor interiors. We show that the CRAIT strategy allows the deep tumor penetration of drug-loaded nanoparticles, resulting in enhanced therapeutic efficacy in an orthotopic 4T1 breast tumor model. The CRAIT strategy does not require ex vivo manipulation of cells and can be applied to various types of cells and nanovehicles.
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