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Three-dimensional topological insulators (3D TI) exhibit conventional parabolic bulk bands and protected Dirac surface states. A thorough investigation of the different transport channels provided by the bulk and surface carriers using macroscopic samples may provide a path toward accessing superior surface transport properties. Bi2 Te3 materials make promising 3D TI models; however, due to their complicated defect chemistry, these materials have a high number of charge carriers in the bulk that dominate the transport, even as nanograined structures. To partially control the bulk charge carrier density, herein the synthesis of Te-enriched Bi2 Te3 nanoparticles is reported. The resulting nanoparticles are compacted into nanograined pellets of varying porosity to tailor the surface-to-volume ratio, thereby emphasizing the surface transport channels. The nanograined pellets are characterized by a combination of resistivity, Hall- and magneto-conductance measurements together with (THz) time-domain reflectivity measurements. Using the Hikami-Larkin-Nagaoka (HLN) model, a characteristic coherence length of 200 nm is reported that is considerably larger than the diameter of the nanograins. The different contributions from the bulk and surface carriers are disentangled by THz spectroscopy, thus emphasizing the dominant role of the surface carriers. The results strongly suggest that the surface transport carriers have overcome the hindrance imposed by nanoparticle boundaries. © 2023 The Authors. Small published by Wiley-VCH GmbH.

Dry reforming of methane (DRM) has been emerging as a viable solution to achieving carbon neutrality enhanced by the Paris Agreement as it converts the greenhouse gases of CO

Dry reforming of methane (DRM) is a feasible solution to cope with the reduction of greenhouse gas under the Paris Convention's obligations, given that it adds value by converting trivial gases of CO2 and CH4 simultaneously into useful syngas. However, conventional Ni catalyst undergoes deactivation due to carbon coking and particle agglomeration. Here we demonstrate for the first time a highly efficient and durable DRM catalyst of exsolved Co-Ni-Fe ternary alloy nanoparticles on the layered perovskite PrBaMn1.7Co0.1Ni0.2O5+d produced by topotactic exsolution. This readily allows the generation of a larger number of exsolved nanoparticles, enhancing catalytic activity above those of Ni monometallic and Co-Ni bimetallic particles. The enhancement is achieved by the optimal up-shift of the d-band center of Co-Ni-Fe than those of Co-Ni and Ni meaning easier charge donation to the adsorbate. Furthermore, the exsolved catalyst shows exceptional stability with the continuous DRM operation for about 350 hours.

Single-atom catalysts (SACs) have emerged as promising materials in heterogeneous catalysis. Previous studies reported controversial results about the relative level in activity for SACs and nanoparticles (NPs). These works have focused on the effect of metal atom arrangement, without considering the oxidation state of the SACs. Here, we immobilized Pt single atoms on defective ceria and controlled the oxidation state of Pt SACs, from highly oxidized (Pt0 : 16.6 at %) to highly metallic states (Pt0 : 83.8 at %). The Pt SACs with controlled oxidation states were then employed for oxidation of CO, CH4 , or NO, and their activities compared with those of Pt NPs. The highly oxidized Pt SACs presented poorer activities than Pt NPs, whereas metallic Pt SACs showed higher activities. The Pt SAC reduced at 300 °C showed the highest activity for all the oxidations. The Pt SACs with controlled oxidation states revealed a crucial missing link between activity and SACs.

Aim This study attempts to determine the factors affecting problem behaviour and academic performance of children with asthma. Design This is a cross‐sectional study used actor and partner interdependence model. Methods Data of 236 children and their parents from the 10th Panel Study on Korean Children were used, and analysis was performed using SPSS 20.0 and AMOS 20.0. We have received panel data from the Korea Institute of Child Care and Education on April 10th, 2019. Results Parental depression had actor and partner effects on marital conflict, and marital conflict perceived by the father had actor and partner effects on parent–child interactions, while marital conflict perceived by the mother had only actor effect on parent–child interactions. Parent–child interaction perceived by both fathers and mothers was found to affect the problem behaviour of children. The problem behaviour of children affects academic performance.

Methane upgrading into more valuable chemicals has received much attention. Herein, we report oxidative methane conversion to ethane using gaseous O2 at low temperatures (

Hydroxyapatite (HAP) is a green catalyst which has a wide range of applications in the catalysis due to its high flexibility and multi-functionality. These properties allow HAP to accommodate a large number of catalyst modifications that can selectively improve the catalytic performance in target reactions. To date, many studies have been conducted to elucidate the effect of HAP modification on the catalytic activities for various reactions. However, systematic design strategies for HAP catalysts are not established yet due to incomplete understanding of underlying structure-activity relationships. In this review, tuning methods of HAP for improving the catalytic performance are discussed: (1) ionic composition change, (2) morphology control, (3) incorporation of other metal species, and (4) catalytic support engineering. We investigate detailed mechanisms and effects of structural modulations on the catalytic performances for attaining the design insights of HAP catalysts. In addition, computational studies to understand catalytic reactions on HAP materials are also introduced. Finally, important areas for future research are highlighted. This article is protected by copyright. All rights reserved.

High-energy and long cycle lithium-sulfur (Li-S) pouch cells are limited by the insufficient capacities and stabilities of their cathodes under practical electrolyte/sulfur (E/S), electrolyte/capacity (E/C), and negative/positive (N/P) ratios. Herein, an advanced cathode comprising highly active Fe single-atom catalysts (SACs) are reported to form 320.2 W h kg

To separately explore the importance of hydrophilicity and backbone planarity of polymer photocatalyst, a series of benzothiadiazole-based donor-acceptor alternating copolymers incorporating alkoxy, linear oligo(ethylene glycol) (OEG) side chain, and backbone fluorine substituents is presented. The OEG side chains in the polymer backbone increase the surface energy of the polymer nanoparticles, thereby improving the interaction with water and facilitating electron transfer to water. Moreover, the OEG-attached copolymers exhibit enhanced intermolecular packing compared to polymers with alkoxy side chains, which is possibly attributed to the self-assembly properties of the side chains. Fluorine substituents on the polymer backbone produce highly ordered lamellar stacks with distinct π-π stacking features; subsequently, the long-lived polarons toward hydrogen evolution are observed by transient absorption spectroscopy. In addition, a new nanoparticle synthesis strategy using a methanol/water mixed solvent is first adopted, thereby avoiding the screening effect of surfactants between the nanoparticles and water. Finally, hydrogen evolution rate of 26 000 µmol g

ATPase inhibitory factor 1 (IF1) is an ATP synthase–interacting protein that suppresses the hydrolysis activity of ATP synthase. In this study, we observed that the expression of IF1 was up-regulated in response to electrical pulse stimulation of skeletalmuscle cells and in exercized mice and healthy men. IF1 stimulates glucose uptake viaAMPKin skeletalmuscle cells and primary culturedmyoblasts.Reactive oxygen species and Rac family small GTPase 1 (Rac1) function in the upstream and downstream of AMPK, respectively, in IF1-mediated glucose uptake. In diabetic animal models, the administration of recombinant IF1 improved glucose tolerance and down-regulated blood glucose level. In addition, IF1 inhibitsATPhydrolysis byb-F1-ATPase inplasmamembrane, thereby increasing extracellular ATP and activating the protein kinase B (Akt) pathway, ultimately leading to glucose uptake. Thus, we suggest that IF1 is a novel myokine and propose amechanismby which AMPK and Akt contribute independently to IF1-mediated improvement of glucose tolerance impairment. These results demonstrate the importance of IF1 as a potential antidiabetic agent.

Single-atom catalysts (SACs) have attracted growing attention because they maximize the number of active sites, with unpredictable catalytic activity. Despite numerous studies on SACs, there is little research on the support, which is essential to understanding SAC. Herein, we systematically investigated the influence of the support on the performance of the SAC by comparing with single-atom Pt supported on carbon (Pt SA/C) and Pt nanoparticles supported on WO3-x (Pt NP/WO3-x ). The results revealed that the support effect was maximized for atomically dispersed Pt supported on WO3-x (Pt SA/WO3-x ). The Pt SA/WO3-x exhibited a higher degree of hydrogen spillover from Pt atoms to WO3-x at the interface, compared with Pt NP/WO3-x , which drastically enhanced Pt mass activity for hydrogen evolution (up to 10 times). This strategy provides a new framework for enhancing catalytic activity for HER, by reducing noble metal usage in the field of SACs.

3D topological insulators (TI) host surface carriers with extremely high mobility. However, their transport properties are typically dominated by bulk carriers that outnumber the surface carriers by orders of magnitude. A strategy is herein presented to overcome the problem of bulk carrier domination by using 3D TI nanoparticles, which are compacted by hot pressing to macroscopic nanograined bulk samples. Bi2 Te3 nanoparticles well known for their excellent thermoelectric and 3D TI properties serve as the model system. As key enabler for this approach, a specific synthesis is applied that creates nanoparticles with a low level of impurities and surface contamination. The compacted nanograined bulk contains a high number of interfaces and grain boundaries. Here it is shown that these samples exhibit metallic-like electrical transport properties and a distinct weak antilocalization. A downward trend in the electrical resistivity at temperatures below 5 K is attributed to an increase in the coherence length by applying the Hikami-Larkin-Nagaoka model. THz time-domain spectroscopy reveals a dominance of the surface transport at low frequencies with a mobility of above 103 cm2 V-1 s-1 even at room temperature. These findings clearly demonstrate that nanograined bulk Bi2 Te3 features surface carrier properties that are of importance for technical applications. © 2021 The Authors. Small published by Wiley-VCH GmbH.

The rapid transport of alkali ions in electrodes is a long-time dream for fast-charging batteries. Though electrode nanostructuring has increased the rate-capability, its practical use is limited because of the low tap density and severe irreversible reactions. Therefore, development of a strategy to design fast-charging micron-sized electrodes without nanostructuring is of significant importance. Herein, a simple and versatile strategy to accelerate the alkali ion diffusion behavior in micron-sized electrode is reported. It is demonstrated that the diffusion rate of K

Purpose The purpose of this study is to test a structural model that analyzes and comprehensively identifies the factors that affect the psychological well-being of hospital nurses, and to reveal the direct and indirect relationships among the factors. Method The subjects of this study were 217 nurses working in four advanced general hospitals in Metropolitan City B and Province G with at least one experience of job rotation. Data were analyzed using SPSS 21.0. The characteristics of subjects and the reliability of the research tools were analyzed through descriptive statistics, a t-test, an analysis of variance, and correlation analyses on the research variables. A confirmatory factor analysis was performed using AMOS 21.0 to verify the fitness of the hypothetical model and hypothesis. Results The test of fitness of the hypothetical model yielded χ2 = 152.14, df = 72, χ2 /df = 2.11, goodness of fit index = .97, adjusted goodness of fit index = .91, normed fit index = .95, comparative fit index = .98, root mean square = .02, and root mean square error of approximation = .01, which showed that the model had a good fit and explained 63.0% of the variance in psychological well-being. The hypothesis of the study was verified: Nurses' job rotation stress has indirect effect on psychological well-being through self-efficacy, social support, optimism, and coping strategies. Conclusion A practical method that can promote self-efficacy, social support, optimism, and stress-coping strategies must be established to improve the psychological well-being of hospital nurses based on this research.

Aim To examine the resilience of breast cancer patients by investigating the validity and reliability of a Korean version of the breast cancer survivors resilience scale (BCRS) and to provide basic data for developing interventions that can be used by healthcare professionals to enhance the resilience of breast cancer patients. Methods Data were obtained from 280 breast cancer survivors receiving treatment at the outpatient clinic of Kosin University Hospital located in Busan City, Korea, and the collected data were used to confirm content validity, construct validity, criterion validity, and internal consistency reliability. Results The Korean version of the BCRS comprised two subdomains and a total of 16 items, and the internal consistency reliability estimated by Cronbach's alpha was .87~.89. Conclusion This study found that the Korean version BCRS has high validity and reliability. In future studies, it will be necessary to conduct research that identifies the resilience levels of patients with breast cancer, using the Korean version BCRS, and seeks interventions in agreement with the results.

OA Förderung 2021 The discovery of graphene and its unique optical and electronic properties has triggered intense developments in a vast number of optoelectronic applications, especially in spectral regions that are not easily accessible with conventional semiconductors. Particularly in the THz regime, where the free-carrier interaction with low-energetic photons usually dominates, detectors and modulators based on graphene often feature an improved response time. Nevertheless, the light−matter interaction suffers from the small interaction volume. One way to enhance the efficiency of such devices at elevated frequencies is by patterning graphene into plasmonic structures like disks. In addition to the increased linear absorption, the plasmon resonance also creates a strong, surface-localized field that enhances the nonlinear optical response. While experimental studies so far have focused on hot carrier effects, theoretical studies also suggest an increase in the nonlinearity beyond thermal effects. Herein, polarization-dependent pump-probe measurements on graphene disks that disentangle the contributions of thermal and plasmonic nonlinearity are presented. An increase in the pump-induced transmission is observed when pump and probe radiation are copolarized. To further elucidate the interplay of thermal and plasmonic effects, a model that supports the origin of the polarization-dependent enhancement of the observed THz nonlinearities is developed.

To identify high-efficiency metal-nitrogen-doped (M-N-C) electrocatalysts for the electrochemical CO2 -to-CO reduction reaction (CO2 RR), a method that uses density functional theory calculation is presented to evaluate their selectivity, activity, and structural stability. Twenty-three M-N4 -C catalysts are evaluated, and three of them (M = Fe, Co, or Ni) are identified as promising candidates. They are synthesized and tested as proof-of-concept catalysts for CO2 -to-CO conversion. Different key descriptors, including the maximum reaction energy, differences of the *H and *CO binding energy (ΔG*H -ΔG*CO ), and *CO desorption energy (ΔG*CO→CO(g) ), are used to clarify the reaction mechanism. These computational descriptors effectively predict the experimental observations in the entire range of electrochemical potential. The findings provide a guideline for rational design of heterogeneous CO2 RR electrocatalysts.

Aims/Introduction The primary aim of this systematic review was to provide an overview of the efficacy and safety of premixed insulin analogs in Asians, specifically East Asians, with type 2 diabetes. Material and Methods The MEDLINE, Embase, Cochrane Library and ClinicalTrials.gov databases were searched from 1 January 1995 to 26 November 2015. Randomized controlled trials involving East Asians with type 2 diabetes treated with any premixed insulin analog were included. Major comparator treatments were basal insulin and basal–bolus insulin. Comparisons were also made between East Asian and Caucasian patients. The primary efficacy outcome was glycated hemoglobin change from baseline to end-point. The primary safety outcome was the incidence of hypoglycemia. Results A total of 21 studies were included; most (n = 14) were carried out in China or Japan. The duration of treatment ranged from 12 to 48 weeks. The glycated hemoglobin mean/least squares mean change from baseline to end-point after treatment with premixed insulin analogs ranged from −0.12 to −4.2% (improvement was generally more pronounced with insulin initiation vs intensification). The incidence of hypoglycemia ranged from 8.3 to 72.0% in most studies, with the variability reflecting the definition of hypoglycemia used. Efficacy and safety outcomes for premixed insulin analogs were generally similar to those for basal or basal–bolus insulin. Limited evidence suggests that dosing, efficacy and safety profiles might differ slightly between East Asian and Caucasians receiving premixed insulin analogs. Conclusions These results support the current use of premixed insulin analogs for managing East Asian patients with type 2 diabetes.

Background In contrast to interscalene block, there was little information regarding the analgesic efficacy of supraclavicular block for shoulder surgery. This study aimed to compare the analgesic efficacy and side effects of interscalene and supraclavicular blocks for shoulder surgery. Methods Patients scheduled for shoulder surgery were assigned to receive either ultrasound-guided interscalene (n = 25) or supraclavicular block (n = 24) with 20 ml of 0.375% ropivacaine. We assessed the duration of post-operative analgesia as a primary outcome and pain scores, supplemental analgesia, diaphragmatic excursion, motor block, fingertip numbness, side effects, and patient satisfaction as secondary outcomes. Results The duration of post-operative analgesia was not statistically different between groups: 868 (800–1440) min for supraclavicular block vs. 800 (731–922) min for interscalene block (median difference −85 min, 95% CI, −283 to 3 min, P = 0.095). The incidence of diaphragmatic paresis was significantly lower in the supraclavicular block group compared with that in the interscalene block group, both at 30 min after the block (66.7% vs. 92%, P = 0.021) and in the post-anaesthesia care unit (62.5% vs. 92%, P = 0.024). Motor block was higher in the supraclavicular block group in the post-anaesthesia care unit, however, not at 24 h. Other secondary outcomes were similar for both groups. Conclusions This study showed no statistically significant difference in the duration of post-operative analgesia between the supraclavicular and interscalene blocks. However, the supraclavicular block was associated with a lower incidence of diaphragmatic paresis compared with that of the interscalene block after shoulder surgery.

A surficial molecular dipole effect depending on ion-molecular interactions has been crucial issues regarding to an interfacial potential, which can modulate solid electronic and electrochemical systems. Their properties near the interfacial region can be dictated by specific interactions between surface and adsorbates, but understandings of the corresponding details remain at interesting issues. Here, intuitive observations of an ionic pair formation-induced interfacial potential shifts are presented with an ionovoltaic system, and corresponding output signal variations are analyzed in terms of the surficial dipole changes on self-assembled monolayer. With aiding of photoelectron spectroscopies and density function theory simulation, the ionic pair formation-induced potential shifts are revealed to strongly rely on a paired molecular structure and a binding affinity of the paired ionic moieties. Chemical contributions to the binding event are interrogated in terms of polarizability in each ionic group and consistent with chaotropic/kosmotropic character of the ionic groups. Based on these findings, the ionovoltaic output changes are theoretically correlated with an adsorption isotherm reflecting the molecular dipole effect, thereby demonstrating as an efficient interfacial molecular probing method under electrolyte interfacing conditions.

The reaction mechanism of glycerol hydrogenolysis to 1,2-propanediol over a spinel CuCr2 O4 catalyst was investigated by using DFT calculations. Theoretical models were developed from the results of experimental characterization. Adsorption configurations and energetics of the reactant, intermediates, final product, and transition states were calculated on Cu(1 1 1) and CuCr2 O4 (1 0 0). Based on our DFT results, we found that the formation of acetol is preferred to that of 3-hydroxypropionaldehyde thermodynamically and kinetically on both surfaces. For glycerol hydrogenolysis to 1,2-propanediol, the CuCr2 O4 surface is less exothermic but more kinetically favorable than the Cu surface. The low activation barrier during the reaction on the CuCr2 O4 surface is attributed to the unique surface structure; the cubic spinel structure provides a stable adsorption site on which reactants are allowed to be dehydrated and hydrogenated easily with the characteristic adsorption configuration. The role of the Cu and Cr atoms in a CuCr2 O4 surface were revealed. The results of reaction tests supported our theoretical calculations.