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Aqueous zinc‐ion batteries (ZIBs) have shown great potential in the fields of wearable devices, consumer electronics, and electric vehicles due to their high level of safety, low cost, and multiple electron transfer. The layered cathode materials of ZIBs hold a stable structure during charge and discharge reactions owing to the ultrafast and straightforward (de)intercalation‐type storage mechanism of Zn2+ ions in their tunable interlayer spacing and their abilities to accommodate other guest ions or molecules. Nevertheless, the challenges of inadequate energy density, dissolution of active materials, uncontrollable byproducts, increased internal pressure, and a large de‐solvation penalty have been deemed an obstacle to the development of ZIBs. In this review, recent strategies on the structure regulation of layered materials for aqueous zinc‐ion energy storage devices are systematically summarized. Finally, critical science challenges and future outlooks are proposed to guide and promote the development of advanced cathode materials for ZIBs. [ABSTRACT FROM AUTHOR]

It is still a challenge to develop electrocatalyst for the efficient adsorption and conversion of organic molecule in aqueous media. Herein, a hetero‐interface structure based on CuO@Ni(OH)2 is rationally designed to enhance the performance of benzyl alcohol oxidation to benzoic acid. A high Faradaic efficiency of 99% and the yield of 3.09 mmol cm−2 h−1 are achieved at 1.70 V versus reversible hydrogen electrode, outperforming the previously reported electrocatalysts. Furthermore, a membrane‐free flow electrolyzer was assembled based on CuO@Ni(OH)2 hetero‐interface, exhibiting a much high yielding of benzoic acid (6.73 mmol cm−2 h−1) and hydrogen (0.35 L cm−2 h−1) with excellent stability. Both experimental data and density functional theory calculations verify that the electron is tend to accumulate at the hetero‐interface, thus accelerating the adsorption of reactant and intermediate and reducing the energy barrier of the conversion of benzyl alcohol to benzoic acid. [ABSTRACT FROM AUTHOR]

Although layered double hydroxides (LDHs) are extensively investigated for oxygen electrocatalysis, their development is hampered by their limited active sites and sluggish reaction kinetics. Here, sulfur mismatch substitution of NiFe–LDH (S–LDH) is demonstrated, which are in‐situ deposited on nitrogen‐doped graphene (S–LDH/NG). This atomic‐level sulfur incorporation leads to the construction of the tailored topological microstructure and the modulated electronic structure for the improved catalytic activity and durability of bifunctional electrocatalysts. The combined computational and experimental results clarify that the electron transfer between the sulfur anion and Fe3+ generates the high‐valence Fe4+ species, while the mismatch substitution of the sulfur anion induces the metallic conductivity, an increased carrier density, and the reduced reaction barrier. Consequently, the as‐fabricated Zn–air battery achieves a high power density of 165 mW cm‐2, a large energy density of 772 Wh kgZn‐1 at 5 mA cm‐2, and long cycle stability for 120 h, demonstrating its real‐life operation. [ABSTRACT FROM AUTHOR]

The bean bug Riptortus pedestris causes major damage to soybean and has become a serious problem due to its high resistance to insecticides. To address this problem, this study aimed to select the most effective entomopathogenic fungi for the control of R. pedestris. Selection was performed through the evaluation of virulence, thermotolerance, and UV‐B tolerance of fungal isolates against R. pedestris and conidial production on grain medium. The pathogenicity of 30 Beauveria bassiana isolates and 30 Metarhizium anisopliae isolates was evaluated, and pathogenicity was confirmed in all but 3 isolates of B. bassiana. Among the 57 isolates, 11 exhibited high virulence. Of these 11 isolates, B. bassiana JB13G1W1 and M. anisopliae CB6T1G1 and JB12R3G1 showed the highest virulence of more than 80%. The conidial production of all fungal isolates in millet grain medium was good, ranging from 108 to 109 conidia/g. The UV‐B tolerance and thermotolerance of the 57 isolates varied according to the isolate, and those of M. anisopliae isolates were slightly higher than those of B. bassiana. As a result of comparative evaluation of the virulence, conidial production, thermotolerance, and UV‐B tolerance of fungal isolates, B. bassiana JB13G1W1 and M. anisopliae CB6T1G1 and JB12R3G1 were selected as excellent fungal isolates for the control of R. pedestris. Among them, B. bassiana JB13G1W1 showed the highest virulence, with LC50 and LT50 values of 7.86 × 105 conidia/mL and 5.24 days at 108 conidia/mL, respectively. The most effective growth stage to control R. pedestris with B. bassiana JB13G1W1 was 2nd‐instar nymphs. [ABSTRACT FROM AUTHOR]

The oxidation degradation by unsaturated metal atoms or dangling bonds at MXene edges and defects severely hinders the practical application of MXene. Herein, a passivation scheme for Ti3C2Tx MXene is demonstrated by utilizing a sulfhydryl‐containing molecule, β‐mercaptoethanol (BME), which can significantly suppress the Ti3C2Tx oxidation in various environments, including long‐term storage of Ti3C2Tx aqueous dispersions (2 m), single‐layer Ti3C2Tx‐based devices in humid air (2 m), and high‐temperature environment (12 h). Notably, the nonionic BME does not cause aggregation but maintains the 2D morphology of Ti3C2Tx. A comprehensive investigation of the protection mechanism through density functional theory (DFT) calculations and experimental characterizations reveals that BME is adsorbed especially at the edges and surface defects of MXene (binding energy −1.70 and −1.05 eV), where the degradation starts. Further, the electron‐donating effect of sulfhydryl groups tunes the work function of Ti3C2Tx from 4.70 to 4.39 eV, resulting in improved carrier‐transport performances in MoS2 field‐effect transistors owing to band alignment, where BME–Ti3C2Tx serves as the source electrode. The described methodology can largely contribute to the ultralong service life of 2D Ti3C2Tx without affecting its excellent properties, thereby promoting the practical application of this emerging material. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) exhibit intriguing performance in electrocatalysis owing to their maximized atom utilizations and unique electronic structures, but effective anchoring metal atoms with defined coordination structure on hierarchical integrated electrode remain a challenge. Herein, a fast and facial flame‐assisted strategy is developed to construct oxygen‐coordinated SACs on integrated carbon nanotube (CNT) arrays with promising applications in electrocatalysis. Density functional theory calculations show that oxygen in carbon substrate imparts homogeneous sites for the efficient anchoring of metal atoms, thereby enabling SACs to disperse uniformly and firmly and thus bringing optimized activities. Moreover, the integrated CNT array with abundant oxygen‐containing groups is constructed and has been used as an efficient matrix for anchoring metal atoms (CNT‐O@M) via a flame‐assisted method. The as‐prepared CNT‐O@M (M = Co and Pt as typical examples) shows excellent activities in electrocatalytic oxygen reduction reaction and hydrogen evolution reaction with utilization of active site as high as 75.7%, which is superior to the reported SACs. Particularly, the performance of CNT‐O@M can maintain stably under various harsh conditions, showing a promising prospect in the long‐time applications. The methodology and concept proposed in this work could be extended to the synthesis of a variety of integrated SACs for efficient electrocatalysis. [ABSTRACT FROM AUTHOR]

The intrinsic origin of amyloid aggregation has been pursued as a new pathogenesis for Alzheimer's disease (AD). The aggregation mechanisms influenced by histidine tautomerism were previously investigated in Aβ40 and Aβ42 monomers. In the present study, we focus on the structural properties of Aβ40 heterodimer under the influence of histidine. The results of molecular dynamics simulation detected different aggregation trends were detected in different heterodimers formed by the εεε isomer and other isomers. In the (εεε:δδδ) dimer, the highest β‐sheet content was obtained in the δδδ chain, which is in agreement with our previous studies that δδδ monomer is the most easily formed β‐sheet secondary structure in the monomer. Further analysis confirmed that (εεε:δδδ) dimers more easily aggregate into fibrils in comparison with other heterodimers. This research will help in understanding the tautomeric effect on Aβ heterodimers, thereby helping to figure out the pathogenesis of AD. [ABSTRACT FROM AUTHOR]

Precise control of the local electronic structure and properties of electrocatalysts is important for enhancing the multifunctionality and durability of electrocatalysts and for correlating the structure/chemistry with the catalytic properties. Herein, we report electronically coupled metallic hybrids of NiFe layered double hydroxide nanosheet/Ti3C2 MXene quantum dots deposited on a nitrogen‐doped graphene surface (LDH/MQD/NG) for high‐performance flexible Zn–air batteries (ZABs). As verified from the Mott–Schottky and Nyquist plots, as well as spectroscopic, electrochemical, and computational analyses, the electronic and chemical coupling of LDH/MQD/NG modulates the local electronic and surface structure of the active LDH to provide metallic conductivity and abundant active sites, leading to significantly improved bifunctional activity and electrocatalytic kinetics. The rechargeable ZABs with LDH/MQD/NG hybrids are superior to the previous LDH‐based ZABs, demonstrating a high power density (113.8 mW cm−2) and excellent cycle stability (150 h at 5 mA cm−2). Moreover, the corresponding quasi solid‐state ZABs are completely flexible and practical, affording a high power density of 57.6 mW cm−2 even in the bent state, and in real‐life operation of tandem cells for powering various electronic devices. [ABSTRACT FROM AUTHOR]

Electroluminescence efficiency and operating stability of solution‐processed perovskite light‐emitting diodes (PeLEDs) are limited by luminescence quenching induced by indium or tin released from indium tin oxide (ITO) electrode upon deposition of highly acidic conventional hole injection layer (HIL) (i.e., poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)) and inefficient hole injection into perovskite emitting layer. Here, a synergistic molecular strategy to develop a neutralized gradient HIL, which possesses low acidity and high work function (WF) simultaneously, is proposed. First, it is shown that aniline with relatively low basicity and dipole moment efficiently neutralizes HIL while maintaining its original confirmation and high WF. Both acidity‐neutralizing aniline and WF‐modifying agent (perfluorinated ionomer) are incorporated into PEDOT:PSS to achieve high pH ≈ 6 and WF > 5.8 eV, which suppresses etching of underlying ITO and luminescence quenching while maintaining efficient hole injection into perovskite emitting layer. With this synergetic molecular engineering, high current efficiency = 52.55 cd A−1 with extended operating lifetime is achieved in PeLEDs that use colloidal formamidinium lead bromide nanoparticle films. This result provides a simple and efficient way to develop efficient and stable PeLEDs in industrial displays and solid‐state lighting. [ABSTRACT FROM AUTHOR]

Density functional theory calculations have been performed to study the adsorption behavior of ionic liquids (ILs) on 15th group nanosheets including phosphorene (BP), arsenene (As), and antimonene (Sb). Three ILs based on 1‐ethyl‐3‐methylimidazolium ([EMIM]+), tetramethylammonium ([TMA]+), and N‐methylpyridinium ([MPI]+) cations paired with tetrafluoroborate ([BF4]−) anion were selected as adsorbates on different 2D nanosheets to explore the interfacial behavior. The calculated structural, energy, charge transfer, and electronic properties of the adsorption systems for ILs/nanosheets exhibit combination by non‐covalent interaction. Adsorption of ILs induces a very small reduction of band gap for BP, As, and Sb nanosheets, and the electronic properties of nanosheets are nearly unchanged. These results increase understanding of the experimental mechanism for IL dispersion 2D materials and suggest that ILs can be used to functionalize elemental 15th group nanosheets for further applications in various fields. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) presents with various extraintestinal manifestations. As part of them, various skin diseases are suggested to be related to IBD. We aimed to identify the epidemiology and risk of developing skin manifestations in patients with IBD. We used Korean insurance claims data and selected patients with IBD and age/sex‐matched non‐IBD subjects between 2013 and 2017 using the diagnosis code and prescription records of IBD‐specific medications. The prevalence and risk of concurrent skin diseases were estimated. We identified 64 837 patients with IBD. Reactive skin eruptions including pyoderma gangrenosum and erythema nodosum were associated with IBD with highest odds ratios among three categories of reactive, inflammatory, and autoimmune skin diseases. Inflammatory skin diseases including rosacea, psoriasis, atopic dermatitis, hidradenitis suppurativa, and acne conglobata were significantly associated with IBD, but the association was less marked compared to reactive skin eruptions. The patients with IBD also had a higher risk of autoimmune skin diseases including vitiligo and alopecia areata than non‐IBD subjects. We determined that IBD was related to various skin diseases including reactive, inflammatory, and autoimmune skin diseases. Considering these relationships can allow better management of patients with IBD and comorbid skin diseases. [ABSTRACT FROM AUTHOR]

The development of efficient electrocatalysts for the CO2 reduction reaction (CO2RR) remains a challenge. Demonstrated here is a NiSn atomic‐pair electrocatalyst (NiSn‐APC) on a hierarchical integrated electrode, which exhibits a synergistic effect in simultaneously promoting the activity and selectivity of the CO2RR to formate. The NiSn atomic pair consists of adjacent Ni and Sn, each coordinated with four nitrogen atoms (N4‐Ni‐Sn‐N4). The as‐prepared NiSn‐APC displays exceptional activity for the CO2RR to formate with a turnover frequency of 4752 h−1, a formate productivity of 36.7 mol h−1 gSn−1 and an utilization degree of active sites (57.9 %), which are superior to previously reported single‐atomic catalysts. Both experimental data and density‐functional theory calculations verify the electron redistribution of Sn imposed by adjacent Ni, which reduces the energy barrier of the *OCHO intermediate and makes this potential‐determining step thermodynamically spontaneous. This synergistic catalysis provides a successful paradigm for rational design and preparation of atomic‐pair electrocatalysts with enhanced performance. [ABSTRACT FROM AUTHOR]

Despite being a clinically approved intervention for cancer, photodynamic therapy (PDT) still suffers from limitations. Prime among these is a therapeutic response that is mostly oxygen dependent. This limits the utility of PDT in treating hypoxic tumors since lower levels of cytotoxic reactive oxygen species (ROS) are generated in regions of low oxygen tension. Glutathione‐pi (GST‐pi) is a key enzyme that militates against ROS‐mediated apoptosis. We report herein a new construct, EA‐BPS, that contains both a brominated BODIPY photosensitizer (BPS) and an ethacrynic acid (EA) GST‐pi inhibitor. Photoirradiation of EA‐BPS induces a synergistic antitumor effect that results from the combination of ROS production and GST‐pi inhibition. Relative to BPS alone, an enhanced cell‐killing effect is seen under hypoxic conditions both in vitro and in vivo. We conclude that by making better use of the available oxygen in tumor environments, improved therapeutic PDT outcomes should be achievable even under hypoxic conditions. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is an environmental contaminant that causes renal toxicity. We have previously demonstrated that Cd induces renal toxicity by altering transcriptional activities. In this study, we show that Cd markedly inhibited the activity of transcription factor MEF2A in HK‐2 human proximal tubule cells, which generated significant cytotoxicity in the cells. This reduction in the nuclear levels of MEF2A protein may be involved in the Cd‐induced inhibition of MEF2A activity. We also demonstrate that one of the glucose transporters, GLUT4, was downregulated not only by Cd treatment but also by MEF2A knockdown. Knockdown of SLC2A4, encoding GLUT4, eliminated both cell viability and Cd toxicity. Cd treatment or SLC2A4 deficiency reduced the cellular concentration of glucose. Therefore, the suppression of SLC2A4 expression, which mediates the reduction in cellular glucose, is involved in Cd toxicity. The Cd toxicity induced by the reduction in GLUT4 may be associated with a reduction of cellular ATP levels in HK‐2 cells. The levels of Slc2a4 mRNA in the kidney of mice exposed to Cd for 6 or 12 months were significantly lower than those in the control group. These results demonstrate that Cd exerts its cytotoxicity through the suppression in SLC2A4 expression and the subsequent inhibition of MEF2A transcriptional activity. Cd‐induced suppression of SLC2A4 expression also reduces cellular ATP levels, partly by reducing glucose levels. This study suggests that the glucose transporter plays an important role in the renal toxicity of Cd, and provides a crucial breakthrough in our understanding of the mechanism of Cd toxicity. [ABSTRACT FROM AUTHOR]

To study the hyporheic exchange driven by a single peak flood‐induced water level fluctuation (i.e., flood wave), a method combining numerical simulation with theoretical derivation was proposed based on the Inbuk Stream, Korea, where flooding occurs frequently. The hyporheic exchanges induced by different flood waves were investigated by varying amplitude (A), duration (T), wave type parameter (r), and rising duration (tp), which were adopted from the real‐time stream stage fluctuations. Additionally, the idea of constant upstream flood volume (CUFV) condition for flood waves was put forward, and the effects of "Botan" (T/A) and peak number (N) on hyporheic exchange were studied. The results showed that the hyporheic exchange flux (q) was controlled by the water level h (sine‐type) and its change rate v (cosine‐type), and was proportional to the polynomial of them q∝ (ω∙h + v), where ω is the angular frequency of the flood wave. Based on this mechanism, the influence principles on hyporheic exchanges of the typical flood wave parameters (A, T, r and tp) as well as T/A and N under CUFV condition were clarified. The main characteristic variables of hyporheic exchange, which were maximum aquifer storage and residence time, were positively correlated. They also had positive relations to the integral of the flood wave over time, which increased when the wave became higher, wider, rounder and less skewed. However, when CUFV condition was imposed, the residence time was positively correlated with T/A, whereas the maximum aquifer storage was negatively correlated with T/A. With the increase in N, water exchanged more frequently and some water returned to the stream early, leading to the slight decrease in maximum aquifer storage and residence time. These findings enriched the theory of hyporheic exchange driven by surface water fluctuation and be of great significance to enhance pollutant degradation in the hyporheic zone downstream of reservoirs. [ABSTRACT FROM AUTHOR]

Herein, a temperature‐responsive nanoemulsion film (NEF) system is introduced with spinodal decomposition for in situ thermoset curing. The NEFs, fabricated by alternate layering of nanoemulsion droplets with bacterial cellulose nanofibrils (BCFs) and polyelectrolytes through the layer‐by‐layer (LbL) deposition, show ≈32% increase in Young's modulus compared with those fabricated with polyelectrolytes only. It is determined that such reinforcement stemmed from the presence of BCFs that form fibrillary layers in the NEF matrix. The BCF‐reinforced NEFs show the unprecedented spinodal decomposition behavior; nanoemulsion droplets uniformly dispersed in the NEF network and readily interdiffused to produce microscale oil domains with controlled phase separation rate as well as oil domain size. The insight gained from the thin film‐based microphase separation behavior confirms that NEFs layered with epoxy resin nanoemulsions are materials with promising temperature‐responsive in situ thermoset curing performance. [ABSTRACT FROM AUTHOR]

Bridging the gap between homogeneous and heterogeneous catalysis, the single‐atom catalyst supported on a substrate shows extremely high atom efficiency, low cost, excellent stability, and high activity for CO oxidation. Here, we report the catalytic mechanism of CO oxidation on sulfur‐doped h‐BN. The chemisorption activates O2 via electron transfer from sulfur‐doped h‐BN, inducing a reduction in the bond order of O2 and lengthening the O−O distance. This variation is helpful for the subsequent oxidation of CO. The oxidation process includes O2 adsorption, electron reorganization, and two instances each of CO adsorption, oxygen transfer, and CO2 desorption. The first oxygen transfer from O2 to CO occurs exothermically by ∼−63.8 kcal/mol with a barrier of ∼12.1 kcal/mol, which is thus the rate‐determining step. The significantly enhanced catalytic performance implies that sulfur doping on h‐BN should have potential applications in the areas of metal‐free catalysts with low cost and high activity. [ABSTRACT FROM AUTHOR]

Third order polarizability, (γ) taken from the collective electronic oscillator (CEO) method was used to calculate the two‐photon absorption (TPA) of tetrastyryl‐[2,2]paracyclophane derivatives with different through‐space charge transfer configurations considering various donor and acceptor combinations at the terminal styryl groups. For the virtually same linear absorption, different TPA spectra were obtained. For controlling and fine‐tuning frequency and cross‐sections of TPA the through‐space charge transfer interactions can be used. The results are explained by the electronic density matrices corresponding to governing oscillators in one‐ and two‐photon absorption and the ground state. It is indicated that for the studied systems mainly the lowest four oscillators are responsible for the TPA cross‐sections rather than a simple effective three‐state model. [ABSTRACT FROM AUTHOR]

To enhance the understanding of solute dynamics within the stream‐to‐riparian continuum during flood event‐driven water fluctuation (i.e., flood wave), a variable saturated groundwater flow and solute transport model were developed and calibrated against in situ measurements of the Inbuk stream, Korea, where seasonal flooding prevails. The solute dynamics were further investigated for flood waves (varying by amplitude [A], duration [T], roundness [r], and skewness [tp]) that were parameterised by real‐time stream stage fluctuations. We found that the solute transferred faster and farther in the riparian zone, especially within the phreatic zone, above which in the variable saturated zone the concentration required a significantly longer time, particularly at higher altitudes, to return to the initial state. By comparison, solute transferred shallowly in the streambed where the solute plume exhibited an exponential growth trend from the centre to the bank. The dynamic changes of solute flux and mass along the stream–aquifer interface and stream concentration were linked to the shape of flood wave. As the flood wave became higher (A↗), wider (T↗), rounder (r↘), and less skewed (tp↗), the maximum solute storage in aquifer increased. Maximum stream concentration (Cstrˍmax) not only presented a positive linear relationship with A or tp but also showed a negative logarithmic trend with increasing T or r. The sensitivity of Cstr_max to A was approximately two times that of tp, and between these values, the r was slightly more sensitive than T.Cstrˍmax linearly increased as hydraulic conductivity increased and logarithmically increased as longitudinal dispersivity increased. The former relationship was more sensitive than the latter. [ABSTRACT FROM AUTHOR]

Facile engineering of transitional metal oxide nanoparticles (NPs) homogeneously anchored on graphitic carbon nitride (g‐C3N4) is very important. Herein, we develop a rapid and facile route to synthesize CuO NPs‐ and C, N‐codoped g‐C3N4 nanosheets grown on Ni foil (CuO/CN−C3N4/Ni‐f), derived from the oxidation‐pyrolysis of melamine‐entrapped Cu(II)‐MOF gel in the air. A detailed growth process for the hierarchical structure is studied. The obtained hierarchical structure without any binders used directly as an electrode only needs an overpotential of 223 mV to achieve a current density of 50 mA cm−2 in 0.5 M KOH, implying its highly efficient electrocatalytic activity. Notably, this material also exhibits strong long‐term durability. Free energy calculations show that the intrinsic origin of the outstanding activity is derived from sufficient exposure of active sites for CuO NPs anchored on the nanosheets and high N content. [ABSTRACT FROM AUTHOR]

Background and Aim: Alcoholic hepatitis (AH) ranks among the most costly diseases in South Korea. However, accurate hospitalization incidence rates, mortality rates, and contributing factors have not been investigated in South Korea. This study aimed to provide the nationwide incidence of hospitalization, inhospital mortality, and readmission rates for South Korean patients with AH. Methods: Using the Korean Health Insurance Review and Assessment service database, a total of 39 800 inpatient cases from 2008 to 2012 were identified based on the International Classification of Diseases, 10th Revision diagnosis code for AH (K70.1). Standardized hospitalization incidence and mortality rates were calculated, and logistic regression analysis was performed to identify risk factors for inhospital mortality and readmission. Follow‐up data for those admitted in 2008 were collected to assess readmissions. Results: The standardized incidence rate for AH hospitalization per 105 person/year decreased from 19 in 2008 to 14 in 2012 (P = 0.001). The annual inhospital mortality rate ranged from 0.2% to 0.5%. Inhospital mortality was significantly higher in older patients (odds ratio [OR], 1.36) and those with cirrhosis (OR, 4.40). The readmission rate for patients admitted in 2008 was 34.0%. Male sex (OR, 1.21) and low economic status (OR, 2.35) were significantly associated with readmission, whereas older age (OR, 0.96), cirrhosis (OR, 0.77), and urban residency (OR, 0.68) were inversely associated with readmission. Conclusions: This study captured a 5‐year epidemiologic period in South Korea of patients with AH to reflect the real burden of AH and to provide valuable information to policy‐makers assessing public health priorities. [ABSTRACT FROM AUTHOR]

Magnetorheological elastomer (MRE) specimens were prepared to find the optimum compressive characteristics using different types and amounts of iron powder. A magnetic field of up to 2 T was applied during vulcanization. Among the four types of iron powders, the specimen with round‐shaped carbonyl iron powder and small grain size shows higher magnetic effects than that with bigger and irregularly shaped electrolyte iron powder. However, the compressive modulus of the rubber with electrolyte iron powder is higher without magnetic treatment at a given amount. In general, the bigger and irregularly shaped iron particles tend to move slowly and produce nonuniform distribution when a magnetic field is applied. The experimental results show that the mechanical properties are better when applying a magnetic field of 1.5 T compared with 2.0 T during the specimen vulcanization. Applying a magnetic field of 300 mT during the compression test enhanced the compressive modulus by 12% to 15%. The rate of increase of the modulus decreased exponentially with prestrain. [ABSTRACT FROM AUTHOR]

The development of active and inexpensive electrocatalysts for the oxygen evolution reaction (OER) to promote water splitting has always been a major challenge. Cobalt‐based oxides and sulfides have been actively investigated due to their low cost and high activity. However, the lower intrinsic conductivity of cobalt oxide and the inferior stability of cobalt sulfides still limit their practical application. Herein, CoO was chosen for a proof‐of‐concept study in which the anion‐doping strategy was used to obtain an excellent catalyst. Sulfur incorporation optimizes the charge‐transfer properties and active sites of sulfur‐doped CoO (S‐CoO) and thus gives rise to improved catalytic activity. Besides sulfur doping, the stable framework of the cobalt oxide was well maintained, and thus high stability of S‐CoO throughout the reaction process was ensured. Nanoflake electrocatalyst: Sulfur‐doped CoO nanoflakes with loosely packed structure were fabricated by reaction of Co3O4 nanosheets with thioacetamide (TAA) which was used as both sulfur source and reducing agent (see figure). Sulfur doping optimizes the charge‐transfer properties and the active sites and thus leads to clearly enhanced catalytic activity in the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Functional groups in two‐dimensional (2D) Ti3C2Tx MXene are an important factor influencing electrochemical performance in many applications involving energy storage, electrochemical sensors, and water purification. However, after dimethyl sulfoxide (DMSO) delamination, the effect of surface functionalities in Ti3C2Tx is still unclear and there are no systematic reports on its capacitive behavior. Experiments and theoretical calculations confirm the relationship between different surface functionalities, the DMSO delamination effect, and the electrochemical behavior of the DMSO‐delaminated Ti3C2Tx. The dominant −O and −OH terminations are attributed for surfaces delaminated by using HF [Ti3C2Tx (HF)] and LiF/HCl [Ti3C2Tx (LiF/HCl)], respectively. Theoretical results are also in agreement with experimental results in that −OH terminations are essential for the formation of a free‐standing film. Compared to non‐delaminated Ti3C2Tx (HF) (similar O/F ratios of 1.37 and 1.42), there is a significant DMSO delamination effect for Ti3C2Tx (LiF/HCl) because of different O/F ratios of 2.9 and 3.6. Additionally, the delaminated Ti3C2Tx (LiF/HCl) electrodes deliver a higher capacitance of 508 F cm−3 than that of 333 F cm−3 for the delaminated Ti3C2Tx (HF), although it exhibited lower equivalent series resistance, lower interlayer spacing, and slightly lower specific surface area. This study provides direct and systematic experimental evidence for different functional groups in Ti3C2Tx MXene based on the DMSO delamination effect. Digging your MXene: A significant delamination effect of surface functionalities in Ti3C2Tx is demonstrated experimentally and theoretically. O‐containing functional groups, morphological defect‐free, and small flake size HF‐etched MXene nanosheets are better suited for water splitting, optical electrics, and water purification. Alternatively, hydroxy groups of LiF/HCl‐etched MXene films promote effective ion permeation for energy storage and nuclear purification. [ABSTRACT FROM AUTHOR]

Host molecules with a cavity or scaffold with a limited space have been utilized for photodimerization of trans‐stilbene dimer with [2 + 2] cycloaddition. The degrees of freedom of the molecules inside the cavity are generally constrained. The cycloaddition reaction of trans‐stilbene dimer was investigated for variously constrained with inter‐stilbene distances and torsional angles by ab‐initio calculations at MP2/6‐31G* level of theory. In a very short inter‐stilbene distance, a new multicyclic compound (P1) was obtained, while [2 + 2] cycloaddition product (P2) was obtained from a wide range of geometries. Both inter‐stilbene distance and torsional angle play a pivotal role in determining which product (P1 or P2) could be obtained from the cycloaddition reaction of trans‐stilbene dimer. [ABSTRACT FROM AUTHOR]

A new family of all‐carbon structures is proposed via substituting the sp2 carbon atom in graphene and graphyne with carbon trigons. Owing to the existence of carbon trigons, these porous carbon allotropes are named as trigraphene and trigraphyne. The calculations of geometrical, vibrational, and energetic properties by density functional theory reveal that all these structures are metastable and dynamically stable. It is further disclosed from the electronic band structures that trigraphene and α‐trigraphyne are metal, while β‐trigraphyne and γ‐trigraphyne are semiconductor with indirect band gaps of 0.33 and 0.52 eV, respectively. Our results suggest a strategy to design new carbon materials with desired properties, and these all‐carbon materials would have many interesting applications once obtained. [ABSTRACT FROM AUTHOR]

Elevated levels of nitrate in groundwater are an important concern for health and the environment. The overapplication of nitrogen fertilizer to croplands is one of the major sources of high nitrate content in groundwater. In this study, we analyse the nitrate concentrations in Korean groundwater based on data from groundwater quality monitoring wells ( n = 1,022-2,072), which were sampled twice annually over a recent 13-year analysis period (2001-2013). We report that groundwater nitrate levels are decreasing, despite steadily increasing groundwater use. The maximum nitrate concentration decreased from 168.91 to 48.11 mg/L, whereas the mean values also show a gradual decreasing trend. Non-parametric Mann-Kendall tests on nitrate concentrations also confirm the decreasing trend. The nitrate decrease is more clearly evident in agricultural groundwater as compared to domestic and drinking groundwaters. This decrease of nitrate in groundwater coincides with a large decline in nitrogen fertilizer application due to reduced cropland areas, more sustainable agricultural practices, and progressive improvement of sewage disposal services. This study proposes that the long-term adoption of best practices in agriculture has had a positive impact on groundwater nitrate control. [ABSTRACT FROM AUTHOR]

The use of systemic corticosteroids ( SC) for the treatment of psoriasis is not recommended according to textbooks and guidelines. In clinical practise, however, many physicians frequently prescribe SC for patients with psoriasis. To determine the magnitude of SC prescription for outpatients with psoriasis in Korea and identify factors associated with the use of SC, we used the 2010-2014 nationwide claims data of the Health Insurance Review and Assessment Service of Korea. In frequency analysis for the full scale of prescribed SC, oral methylprednisolone was the most frequently prescribed SC, followed by dexamethasone and betamethasone injections. The prescription rate of SC was 26.4% in outpatient visit episodes for psoriasis. The prescription rate of SC was higher in older patients, Medical Aid recipients, patients who visited office-based physician practices and hospitals, and patients living in non-metropolitan areas. In multiple logistic regression analyses, the older age group and smaller health-care institutions were more associated with the SC prescription. In conclusion, SC were widely prescribed for patients with psoriasis in Korea despite the current guidelines. Both patients' individual and institutional characteristics were associated with the SC prescription. [ABSTRACT FROM AUTHOR]

Titanium (Ti) screw has excellent mechanical property, and osseointegration capacity. However, they require surgery for removal. In contrast, polymer screws are resorbable, but they have poor mechanical properties. In this research, magnesium alloy screws (WE43: Mg-Y-Nd-Zr) that have advantages of titanium and polymer were manufactured. In addition, to increase biocompatibility and control degradation rate, the Mg alloy was coated with hydroxyapatite (HA). Torsion test and corrosion test were performed in vitro. For clinical, radiological and histological evaluation, on the eight rabbits, two HA-coated screws were installed in left tibia, and two noncoated screws were installed in right tibia. Each four rabbits were sacrificed 6 and 12 weeks postoperatively. For hematological evaluation, the same type of screws were installed on both legs. Complete blood count (CBC), Mg2+ concentrate were sampled from the ear central artery on the operation day for a control point, and at 1, 2, 4, 6, 8, and 12 weeks. Mg alloy screws have no differences of biocompatibility according to the HA coating. However, resorption of screw was slower in case of the HA coating. The hematological problem related releasing of Mg was not found. The results suggest that Mg alloy screws have feasibility for clinical application. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1636-1644, 2017. [ABSTRACT FROM AUTHOR]

This work examines nanocomposites based on nanofillers and room-temperature-vulcanized silicone rubber. The carbon nanofillers used were conductive carbon black (CB), carbon nanotubes (CNTs) and graphene (GE). Vulcanizates for CB, GE, CNTs as the only filler and hybrid fillers using CNTs, CB and GE were prepared by solution mixing. The elastic modulus for CNT hybrid with CB at 15 phr (4.65 MPa) was higher than for CB hybrid with GE (3.13 MPa) and CNTs/CB/GE as the only filler. Similarly, the resistance for CNT hybrid with CB at 10 phr (0.41 kΩ) was lower than for CB (0.84 kΩ) at 20 phr and CNTs as the only filler. These improvements result from efficient filler networking, a synergistic effect among the carbon nanomaterials, the high aspect ratio of CNTs and the improved filler dispersion in the rubber matrix. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A key parameter dictating the rate of charge transfer (CT) is reorganization energy ( λ), an energy associated with geometry changes during hole/electron transfer. We show that 'ironing' the inter-ring dihedral angles of oligothiophenes via proper substitutions or insertions (e.g., -OR, -F or -C≡C-), decreases the λ and thus promotes CT according to Marcus equation. Our results demonstrate, to attain a smaller λ, extending oligomer length is only significant if the flattened backbone structure is realized. Of great interest is that external electric fields, which are ubiquitous in electronic devices yet commonly overlooked in the computation of λ, can have a significantly greater impact than conventional substitutions. It is important to emphasize, the responses of λ to external fields is system-dependent. Compared to fused-ring conjugated systems, single-bond connected thiophenes are more sensitive to external fields. Fx lowers the λ (552 meV) of quaterthiophene by almost 80% at the intensity of 1 V/Å, down to a value (125 meV) which is even lower than that of pentacene (154 meV) and rubrene (219 meV) at the same level of theory. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In this review, rational design strategies for pure organic high-spin molecules with strong intramolecular magnetic interactions are presented, mostly focusing on the design of ferromagnetically coupled organic diradicals. After brief introduction of the calculation procedure for intramolecular magnetic coupling constant J using density functional theory (DFT), classification and standardization of magnetic character of well-known stable radicals and coupler units are discussed. Following the development of general strategy for the design of organic high-spin diradical by means of the classification and standardization scheme, applicability of the strategy for making pendent-type organic polyradical using zigzag graphene nanoribbons backbone is demonstrated. In a computational point of view, a scaling procedure and an optimization of Hartree-Fock exact exchange ratio of a hybrid DFT functional for better prediction of the J of diradicals are discussed. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We previously reported that some of the substrate proteins recognized by Hrt3 or Ucc1, a component of Skp1/Cdc53/F-box protein ubiquitin ligase, may include proteins that are involved in the methylmercury toxicity and degraded by the proteasome. In this study, we found that Dld3 and Grs1 bound to Hrt3 and that Eno2 bound to Ucc1 using a yeast two-hybrid screening. We demonstrated that Dld3 and Grs1 are substrates that are ubiquitinated by Hrt3, and Eno2 is a substrate that is ubiquitinated by Ucc1. Moreover, any yeast showing overexpression of Dld3, Grs1, and Eno2 demonstrated higher methylmercury sensitivity. This indicates that Hrt3 and Ucc1 are involved in alleviating the methylmercury toxicity by promoting proteasomal degradation through the ubiquitination of Dld3, Grs1, and Eno2. [ABSTRACT FROM AUTHOR]

Two new heteroleptic blue emitting Ir(III) complexes, EtOCN‐FIracac and tBuCN‐FIracac, and a homoleptic Ir(III) complex, tBu‐FCNIr, consisting of 2′,4″‐difluorophenylpyridine (dfppy) with a cyano (CN) group at the 5′ position of the phenyl and an ethoxy (EtO‐) or tert‐butyl (tBu) group at the 4 position of the pyridine as the main ligands, are synthesized and characterized for phosphorescent organic light‐emitting diodes (PhOLEDs). The dual functionalization of the dfppy core with the electron‐withdrawing CN and electron‐donating EtO‐ or tBu‐ groups leads to improved blue color purity by compensating the bathochromic shift originating from the ancillary ligand of the heteroleptic Ir(III) complex and contributes to the enhancement of the horizontal ratio of emitting dipoles (Θ), which is one of the promising approaches to improve the efficiency of PhOLEDs. PhOLEDs based on tBuCN‐FIracac and EtOCN‐FIracac show one of the highest efficiencies ever achieved for blue color, with maximum external quantum efficiencies (EQEs) of 22.3% (39.2 cd A−1) and 21.5% (35.1 cd A−1), respectively, with a simple device structure; a similar device based on tBu‐FCNIr displays a maximum EQE of 16.2% (23.5 cd A−1). The performance of PhOLEDs based on the two heteroleptic Ir(III) complexes are highly improved compared to tBu‐FCNIr, due to the increased θ and photoluminescence quantum yield (PLQY). [ABSTRACT FROM AUTHOR]

In the present study, density function theory ( DFT) calculations were carried out regarding the electric field effect on the trans-p-hydroxybenzylideneimidazolidinone ( HBDI), which represents the green fluorescent protein ( GFP) chromophore. Structures in the absence or presence of electric fields were fully optimized with the CAM-B3LYP functional, and the corresponding absorption properties were obtained by the time-dependent DFT method. It was found that electric field parallel to the x-axis ( Fx) has the strongest effect on the charge distribution, and, hence the structure and dipole moment, of the ground state. Furthermore, the absorption energy of the neutral and anionic HBDI monomer was significantly affected by Fx. [ABSTRACT FROM AUTHOR]

The article presents a case study of milium-like syringoma (MLS) limited to the neck in a 30-year-old Korean woman with papules on her anterior benign tumour. The patient under histopathology, showing a syringoma with a cyst that consists of laminated keratinous materials. It mentions the role of race or ethnicity in the pathogenesis of the lesions.

We demonstrate that the imidazole-based ligand 1 efficiently produces a coordination polymer gel by simple mixing with Co2+ ion. When the molar ratio of CoCl2 to ligand 1 was less < 1, a red sol was obtained, indicating the formation of an octahedral ( Oh) complex species as occurs with Co(NO3)2. In contrast to G1, when the amount of CoCl2 employed was more than 1 equiv., the color of the gel changed from red to blue ( G2), indicating the formation of mainly a tetrahedral ( Td) complex species. The ionochromic and the piezochromic effects of imidazole-based suprmolecular gel with Co2+ were investigated. These effects of supramolecular gel were controlled by various anions of cobalt, which are due to coordination geometric change of gels. Interestingly, the ionochromic and piezochromic effects of G1 act as AND and OR logic gates in the solid and the gel state. [ABSTRACT FROM AUTHOR]

Objectives This study evaluated implant stability and clinical outcomes obtained with magnesium-incorporated oxidised implants ( Mg titanate) and compared them to those blasted magnesium-incorporated oxidised implants (blasted Mg titanate). Patients and methods Mg titanate was manufactured using the microarc oxidation ( MAO) process. To obtain blasted Mg titanate, the MAO process was performed after blasting with Ti O2 particles. The 15-month, randomised, double -blind clinical trial was conducted on 54 implants in 40 patients ( Mg titanate, 27 implants in 18 subjects; blasted Mg titanate, 27 implants in 22 subjects), in whom 4.0 mm × 10 mm implants were placed to restore the unilateral loss of one or two molars in the mandible. The final prosthesis was attached 3 months postoperatively. Implant stability was measured by the implant stability quotient ( ISQ) and periotest value ( PTV) at the time of implant insertion, and 2, 3, and 15 months postoperatively. Marginal bone loss was evaluated at 2, 6, and 15 months postoperatively. Soft tissue analysis was performed at 15 months postoperatively. Results Both implant systems showed high stability at all time points (>71). Mean marginal bone loss was 0.71 ± 0.65 mm and 0.75 ± 0.73 after 15 months in Mg titanate and blasted Mg titanate, respectively. There were no significant differences between the two implant surfaces with respect to ISQ( P = 0.988), PTV( P = 0.935), and marginal bone loss( P = 0.807) after 15 months. Conclusion The success rate after 1 year of follow-up was 100% for both magnesium-incorporated oxidised implants. There were no significant differences in the clinical outcomes between the two surfaces at 15 months follow-up. [ABSTRACT FROM AUTHOR]

The selective copper-catalyzed borylation of silylalkynes in the presence of a diboron reagent and methanol produced a variety of ( Z)-β-(borylvinyl)silanes. The appropriate use of a selective ligand for copper allows the chemo-, regio-, and stereoselective monoborylation of silylalkynes. The β-regioselectivity of an N-heterocyclic carbene (NHC)-copper catalyst was investigated by DFT calculations. [ABSTRACT FROM AUTHOR]

There is an ongoing need for explosive detection strategies to uncover threats to human security including illegal transport and terrorist activities. The widespread military use of the explosive trinitrotoluene (TNT) for landmines poses another particular threat to human health in the form of contamination of the surrounding environment and groundwater. The detection of explosives, particularly at low picogram levels, by using a molecular sensor is seen as an important challenge. Herein, we report on the use of a fluorescent metal-organic framework hydrogel that exhibits a higher detection capability for TNT in the gel state compared with that in the solution state. A portable sensor prepared from filter paper coated by the hydrogel was able to detect TNT at the picogram level with a detection limit of 1.82 ppt (parts per trillon). Our results present a simple and new means to provide selective detection of TNT on a surface or in aqueous solution, as afforded by the unique molecular packing through the metal-organic framework structure in the gel formation and the associated photophysical properties. Furthermore, the rheological properties of the MOF-based gel were similar to those of a typical hydrogel. [ABSTRACT FROM AUTHOR]

Tiny pores: Benzodifuran moieties were introduced into microporous organic networks (MONs) through a tandem process consisting of Sonogashira coupling of 1,3,5‐triethynylbenzene and 2,5‐diiodo‐1,4‐hydroquinone and intramolecular cyclization. The resultant benzodifuran‐containing MON showed promising photocatalytic activities in the oxidative conversion of primary amines into imines. [ABSTRACT FROM AUTHOR]

The heteroditopic crown ether-based ligand 1 containing the diazafluorenylimino group as a binding site for the Zn2+ and Cs+ was synthesized. The ligand 1 can be gelated in DMSO/water with and without Cs+ in the presence of the Zn2+ ion. Interestingly, the remarkable gelation reinforcement of gel 1 occurred with Cs+ in the presence of Zn2+, which is due to the formation of a sandwich complex. According to DFT calculations, one Zn2+ is bound to two diazafluorenylimino moieties in a tetrahedral structure. In addition, one Cs+ ion is bound to two crown-rings. The Zn2+-diazafluorenylimino ligand gel without Cs+ shows a spherical structure with 250-800 nm diameter, whereas the Zn2+-diazafluorenylimino-based ligand gel with Cs+ shows a fiber structure with 60-70 nm diameter and several micrometers of lengths. The rheological properties of the Zn2+- diazafluorenylimino-based ligand gel were strongly dependent on the presence of Cs+. [ABSTRACT FROM AUTHOR]

We provide a novel strategy to eliminate the epoxy group from the basal plane of graphene platelets. Given that the current reduction methods are unsatisfactory to clean the epoxides or sometimes cause undesirable structure deformations, the proposed strategy restores the original hexagonal carbon network without creating other new defects. To the best of our knowledge, the electric field mediated graphene oxide (GO) reduction has not yet been systematically investigated. The capability would permit the improvement of existing GO reduction methods and assist in the fabrication of high-quality graphitic materials. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]