Despite the recent attention for Li metal anode (LMA) with high theoretical specific capacity of ≈3860 mA h g−1, it suffers from not enough practical energy densities and safety concerns originating ...from the excessive metal load, which is essential to compensate for the loss of Li sources resulting from their poor coulombic efficiencies (CEs). Therefore, the development of high‐performance LMA is needed to realize anode‐minimized Li metal batteries (LMBs). In this study, high‐performance LMAs are produced by introducing a hierarchically nanoporous assembly (HNA) composed of functionalized onion‐like graphitic carbon building blocks, several nanometers in diameter, as a catalytic scaffold for Li‐metal storage. The HNA‐based electrodes lead to a high Li ion concentration in the nanoporous structure, showing a high CE of ≈99.1%, high rate capability of 12 mA cm−2, and a stable cycling behavior of more than 750 cycles. In addition, anode‐minimized LMBs are achieved using a HNA that has limited Li content (≈0.13 mg cm−2), corresponding to 6.5% of the cathode material (commercial NCM622 (≈2 mg cm−2)). The LMBs demonstrate a feasible electrochemical performance with high energy and power densities of ≈510 Wh kgelectrode−1 and ≈2760 W kgelectrode−1, respectively, for more than 100 cycles.
This work reports the following important research points: 1) Li ions can be concentrated on nanopores in an anodic voltage region by ion‐exchange behaviors; 2) 3D‐structured nanocarbon assembly can be an efficient catalytic scaffold for Li metal anode; 3) Anode‐minimized Li metal batteries based on a catalytic scaffold can deliver high energy and power densities with stable cycling behavior.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Development of localized inflammatory environments by M1 macrophages in the cardiac infarction region exacerbates heart failure after myocardial infarction (MI). Therefore, the regulation of ...inflammation by M1 macrophages and their timely polarization toward regenerative M2 macrophages suggest an immunotherapy. Particularly, controlling cellular generation of reactive oxygen species (ROS), which cause M1 differentiation, and developing M2 macrophage phenotypes in macrophages propose a therapeutic approach. Previously, stem or dendritic cells were used in MI for their anti-inflammatory and cardioprotective potentials and showed inflammation modulation and M2 macrophage progression for cardiac repair. However, cell-based therapeutics are limited due to invasive cell isolation, time-consuming cell expansion, labor-intensive and costly ex vivo cell manipulation, and low grafting efficiency. Here, we report that graphene oxide (GO) can serve as an antioxidant and attenuate inflammation and inflammatory polarization of macrophages via reduction in intracellular ROS. In addition, GO functions as a carrier for interleukin-4 plasmid DNA (IL-4 pDNA) that propagates M2 macrophages. We synthesized a macrophage-targeting/polarizing GO complex (MGC) and demonstrated that MGC decreased ROS in immune-stimulated macrophages. Furthermore, DNA-functionalized MGC (MGC/IL-4 pDNA) polarized M1 to M2 macrophages and enhanced the secretion of cardiac repair-favorable cytokines. Accordingly, injection of MGC/IL-4 pDNA into mouse MI models attenuated inflammation, elicited early polarization toward M2 macrophages, mitigated fibrosis, and improved heart function. Taken together, the present study highlights a biological application of GO in timely modulation of the immune environment in MI for cardiac repair. Current therapy using off-the-shelf material GO may overcome the shortcomings of cell therapies for MI.
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IJS, KILJ, NUK, PNG, UL, UM
A novel ionic mixture of an imidazolium‐based room‐temperature ionic liquid containing ethylene‐oxide‐functionalized phosphite anions is fabricated, which, when doped with lithium salt, ...self‐assembles into a smectic‐ordered ionic liquid crystal through Coulombic interactions between the ion species. Interestingly, the smectic order in the ionic‐liquid‐crystal ionogel facilitates ionic transport.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background High-quality bowel preparation is a prerequisite for colonoscopy. Few studies have evaluated visual aids as a means of improving the quality of bowel preparation. Objective To assess the ...effect of patient education by using cartoon visual aids on the quality of bowel preparation. Design An endoscopist-blinded, randomized, controlled trial. Setting Tertiary referral center. Subjects Patients scheduled for screening colonoscopy in a health examination center. Interventions Patients were assigned to receive the existing verbal and written instructions (group A) or a new cartoon visual educational instruction (group B) for colonoscopy. Main Outcome Measurements The primary endpoint was the quality of bowel preparation, assessed by using the Boston Bowel Preparation Scale (BBPS). Secondary endpoints were the quality of bowel preparation assessed by using the Universal Preparation Assessment Scale; insertion, withdrawal, and workup times; and polyp detection rates in the 2 groups. Logistic regression analysis was performed to determine the factors associated with poor bowel preparation according to a BBPS score less than 5. Results Group B exhibited better bowel preparation than group A according to BBPS scores (mean BBPS score, 6.12 ± 2.19 vs 7.44 ± 1.87, P ≤ .01; median BBPS score, 6.00 ± 0.00 vs 9.00 ± 0.00, P ≤ .01; good bowel preparation for colonoscopy, BBPS score ≥5, 81.6% vs 93.1%, P = .02). Multivariate analysis revealed that older age (odds ratio 1.07, P ≤ .01) and no use of visual aids (odds ratio 3.08, P = .02) were independent factors associated with poor bowel preparation. Limitations Single-center study. Conclusions Patient education with cartoons effectively improved bowel preparation for colonoscopy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
When graphene is shrunk into ~10 nm scale graphene nanoribbons or nanomesh structures, it is expected that not only electrical properties but also thermal conductivity and thermoelectric property are ...significantly altered due to the quantum confinement effect and extrinsic phonon-edge scattering. Here, we fabricate large-area, sub-10 nm single- and bilayer graphene nanomeshes from block copolymer self-assembly and measure the thermal conductivity, thermoelectric and electrical transport properties to experimentally verify the effect of sub-10 nm quantum confinement, phonon-edge scattering and cross-plane coupling. Among the large variety of the samples, bilayer graphene nanomesh having 8 nm-neck width showed significantly low thermal conductivity down to ~78 W m-1 K-1, which is the lowest thermal conductivity for suspended graphene nanostructures, and a high thermopower value of -520 μV K-1, while it still shows the comparably high carrier mobility. Classical and quantum mechanical calculations successfully supported our nanomesh approach, which can achieve high thermoelectric properties based on the significantly reduced thermal conductivity and higher thermopower due to the confined geometry.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The galvanostatic lithiation/sodiation voltage profiles of hard carbon anodes are simple, with a sloping drop followed by a plateau. However, a precise understanding of the corresponding redox sites ...and storage mechanisms is still elusive, which hinders further development in commercial applications. Here, a comprehensive comparison of the lithium‐ and sodium‐ion storage behaviors of hard carbon is conducted, yielding the following key findings: 1) the sloping voltage section is presented by the lithium‐ion intercalation in the graphitic lattices of hard carbons, whereas it mainly arises from the chemisorption of sodium ions on their inner surfaces constituting closed pores, even if the graphitic lattices are unoccupied; 2) the redox sites for the plateau capacities are the same as those for the closed pores regardless of the alkali ions; 3) the sodiation plateau capacities are mostly determined by the volume of the available closed pore, whereas the lithiation plateau capacities are primarily affected by the intercalation propensity; and 4) the intercalation preference and the plateau capacity have an inverse correlation. These findings from extensive characterizations and theoretical investigations provide a relatively clear elucidation of the electrochemical footprint of hard carbon anodes in relation to the redox mechanisms and storage sites for lithium and sodium ions, thereby providing a more rational design strategy for constructing better hard carbon anodes.
A comprehensive comparison of the lithium‐ and sodium‐ion storage behaviors of hard carbon is conducted, yielding the key findings: the sloping voltage section is presented by the lithium‐ion intercalation in the graphitic lattices of hard carbons, whereas it mainly arises from the chemisorption of sodium ions. The intercalation preference and the plateau capacity have an inverse correlation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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•Patients with NAFLD had alterations in cardiac remodeling.•Hepatic steatosis and fibrosis are associated with diastolic heart dysfunction.•Those without NAFLD were more likely to ...have higher myocardial glucose uptake.•Hepatic fibrosis was correlated with decreased myocardial glucose uptake.
Non-alcoholic fatty liver disease (NAFLD) is associated with increased cardiovascular risk. Among categories of NAFLD, hepatic fibrosis is most likely to affect mortality. Myocardial function and its energy metabolism are tightly linked, which might be altered by an insulin resistant condition such as NAFLD. We investigated whether hepatic steatosis and fibrosis were associated with myocardial dysfunction relative to myocardial glucose uptake.
A total of 308 patients (190 without NAFLD, 118 with NAFLD) were studied in a tertiary care hospital. Myocardial glucose uptake was evaluated at fasted state using 18F-fluorodeoxyglucose-positron emission tomography (18FDG-PET). Hepatic steatosis and fibrosis were assessed by transient liver elastography (Fibroscan®) with controlled attenuation parameter, which quantifies hepatic fat and by surrogate indices (fatty liver index and NAFLD fibrosis score). Cardiac structure and function were examined by echocardiogram.
Compared to those without NAFLD, patients with NAFLD had alterations in cardiac remodeling, manifested by increased left ventricular mass index, left ventricular end-diastolic diameter, and left atrial volume index (all p <0.05). Hepatic steatosis was significantly associated with left ventricular filling pressure (E/e’ ratio), which reflects diastolic dysfunction (p for trend <0.05). Those without NAFLD were more likely to have higher myocardial glucose uptake compared to those with NAFLD. Significant hepatic fibrosis was also correlated with diastolic dysfunction and impaired myocardial glucose uptake. Using multivariable linear regression, E/e’ ratio was independently associated with hepatic fibrosis (standardized β = 0.12 to 0.27; all p <0.05). Association between hepatic steatosis and E/e’ ratio was also significant (standardized β = 0.10 to 0.15; all p <0.05 excluding the model adjusted for adiposity).
Hepatic steatosis and fibrosis are significantly associated with diastolic heart dysfunction. This association is linked with myocardial glucose uptake evaluated by 18FDG-PET.
Non-alcoholic fatty liver disease is associated with an increased risk of cardiovascular disease. More severe forms of non-alcoholic fatty liver disease, where hepatic fibrosis occurs, are linked to increased mortality. In this study, we have shown that hepatic steatosis and fibrosis are associated with subclinical myocardial dysfunction. This association is linked to altered myocardial glucose uptake.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Cholesteric liquid crystals (CLCs) reflect selected wavelengths of light owing to their periodic helical structures. The encapsulation of CLCs leads to photonic devices that can be easily processed ...and might be used as stand‐alone microsensors. However, when CLCs are enclosed by polymeric membranes, they usually lose their planar alignment, leading to a deterioration of the optical performance. A microfluidics approach was employed to integrate an ultrathin alignment layer into microcapsules to separate the CLC core and the elastomeric solid membrane using triple‐emulsion drops as the templates. The thinness of the alignment layer provides high lubrication resistance, preserving the layer integrity during elastic deformation of the membrane. The CLCs in the microcapsules can thus maintain their planar alignment, rendering the shape and optical properties highly reconfigurable.
Photonic microcapsules: Cholesteric liquid crystals (CLCs) are encapsulated by a double layer consisting of an ultrathin alignment layer and an elastic membrane in a microfluidic approach. The alignment layer induces the liquid crystals to adopt a planar alignment, and the elastic membrane renders the microcapsules reconfigurable.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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•PBI containing two (DOPBI) and three (TOPBI) ether groups in a repeating unit.•DOPBI and TOPBI having better solubility in organic solvents than m-PBI or OPBI.•DOPBI and TOPBI with ...lower glass transition temperature than m-PBI or OPBI.
Polybenzimidazoles (PBIs) containing two and three ether groups per a repeating unit are prepared to improve the processability of the PBI system for the first time. Poly2,2′-(m-phenylene)-1,4-bis(5-oxybenzimidazole)benzene (DOPBI, PBI containing two ether groups per a repeating unit) is synthesized using 1,4-bis(3,4-diaminophenoxy)benzene (DAPB) and isophthalic acid and poly2,2′-(p-oxydiphenylene)-1,4-bis(5-oxybenzimidazole)benzene (TOPBI, PBI containing three ether groups per a repeating unit) is prepared through the reaction between DAPB and 4,4′-oxybis(benzoic acid). DAPB is synthesized by reducing 1,4-bis(3,4-dinitrophenoxy)benzene (DNPB), which is obtained by reacting 3,4-dinitrochlorobenzene and hydroquinone. The thermal properties, mechanical properties, and solubility of DOPBI, TOPBI, poly2,2′-(m-phenylene)-5,5′-bisbenzimidazole (m-PBI), and poly2,2′-(p-oxydiphenylene)-5,5′-bibenzimidazole (OPBI) are systemically studied. As expected, DOPBI and TOPBI show better solubility in various organic solvents compared to m-PBI with no ether group and OPBI with only one ether group per a repeating unit. Furthermore, DOPBI and TOPBI show much smaller glass transition temperature (Tg) values (346 °C and 321 °C, respectively) than m-PBI (above 400 °C) and OPBI (373 °C), indicating an improved melt processability. In molecular dynamics simulations for estimating the Tg values of PBIs, DOPBI and TOPBI are also found to have smaller Tg values (352.5 °C and 302.2 °C, respectively) than OPBI consistent with actual experimental data.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The staging of potassium-ion intercalation reactions with graphite-like carbon materials has been previously chronicled; however, the potassium-ion storage behavior of disordered graphitic carbons ...(DGCs) has not been elucidated owing to their complex microstructures and the lack of systematic studies. In this study, microstructure-engineered DGCs were prepared using natural polymers by simple pyrolysis, followed by high-temperature annealing from 1200 °C to 2800 °C, and their potassium-ion storage properties were investigated and compared with their lithium-ion storage characteristics. In contrast to the lithium-ion intercalation reactions, which are dependent on local graphitic ordering, the stage I potassium-ion intercalation reaction was found to occur in highly disordered graphitic structures with a few nanometer-sized graphitic domains and an expanded
d
-spacing of >3.5 Å. In addition, the potassium-ion intercalation reactions with the highly expanded graphitic lattices were considerably faster and more stable compared to those with the highly developed disordered graphitic structures. These results suggest that hard carbons with a loosely packed disordered graphitic structure can be employed as effective high-performance anode materials for potassium-ion batteries.
A distinctive solid-solution potassium-ion intercalation behavior of disordered graphitic carbon materials was observed.
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