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Ca2+ overload-induced mitochondrial dysfunction is considered as a major contributing factor in the pathogenesis of alcohol-associated liver disease (ALD). However, the initiating factors that drive mitochondrial Ca2+ accumulation in ALD remain elusive. Here, we demonstrate that an aberrant increase in hepatic GRP75-mediated mitochondria-associated ER membrane (MAM) Ca2+-channeling (MCC) complex formation promotes mitochondrial dysfunction in vitro and in male mouse model of ALD. Unbiased transcriptomic analysis reveals PDK4 as a prominently inducible MAM kinase in ALD. Analysis of human ALD cohorts further corroborate these findings. Additional mass spectrometry analysis unveils GRP75 as a downstream phosphorylation target of PDK4. Conversely, non-phosphorylatable GRP75 mutation or genetic ablation of PDK4 prevents alcohol-induced MCC complex formation and subsequent mitochondrial Ca2+ accumulation and dysfunction. Finally, ectopic induction of MAM formation reverses the protective effect of PDK4 deficiency in alcohol-induced liver injury. Together, our study defines a mediatory role of PDK4 in promoting mitochondrial dysfunction in ALD.

Purpose This study aims to introduce a deep neural network (DNN) to estimate the effective thermal conductivity of the flat heat pipe with spreading thermal resistance. Design/methodology/approach A total of 2,160 computational fluid dynamics simulation cases over up to 2,000 W/mK are conducted to regress big data and predict a wider range of effective thermal conductivity up to 10,000 W/mK. The deep neural networking is trained with reinforcement learning from 10–12 steps minimizing errors in each step. Another 8,640 CFD cases are used to validate. Findings Experimental, simulational and theoretical approaches are used to validate the DNN estimation for the same independent variables. The results from the two approaches show a good agreement with each other. In addition, the DNN method required less time when compared to the CFD. Originality/value The DNN method opens a new way to secure data while predicting in a wide range without experiments or simulations. If these technologies can be applied to thermal and materials engineering, they will be the key to solve thermal obstacles that many longing to overcome.

Developing catalysts with outstanding performance for oxygen evolution reaction (OER) is crucial to advance energy conversion technologies. In these regards, catalysts based on 3d transition metals have recently attracted much attention, yet further development is required. Here, we present a new type of heterostructure catalyst in which CoO nanowire arrays are hybridized with tungsten nanoparticles (W-CoO), and are self-supported on conductive carbon cloth (CC). Electronic coupling effects at the W-CoO heterointerface promote electron transfer and OER kinetics to expedite the formation of oxyhydroxide species, which are the active sites for OER processes. A variety of in situ and ex situ characterization methods are employed to reveal deep insights into surface transformations and investigate the relationship between the conversion to oxyhydroxide moieties and OER performance. This report presents new understanding of the rational design and synthesis of catalysts that exhibit outstanding performance as electrochemical water splitting electrode for OER.

Objective: Endoscopic surgical procedures rigorously underscore the significance of rapid hemostasis for unavoidable intraoperative bleeding, requiring advancement of the immediate hemostatic interventions for favorable clinical outcomes. Here, we report the efficacy of a new optical treatment with dual-wavelengths to develop an endoscopic hemostasis method. Methods: we combine visible (20-W 532 nm at 1.1 kW/cm2) and near-infrared (40-W 980 nm at 2.2 kW/cm2) wavelengths for facilitating noncontact thermal hemostasis on venous and arterial bleeders in in vivo leporine models. Results: Simultaneous irradiation of 60-W dual-wavelengths allows for an increased irradiance of 3.3 kW/cm2, involving both rapid light absorption by hemoglobin and deep thermal penetration. The collective thermal effects from the combined wavelengths contribute to a significant reduction in coagulation time and a high success rate of complete hemostasis for both venous and arterial bleeders. The enhanced hemostatic potential of the dual-wavelengths treatment accompanies minimal hemorrhage, reduces inflammatory responses, and facilitates re-epithelialization. Conclusion: The proposed dual-wavelengths method can achieve rapid and complete hemostasis for endoscopic procedures. Significance: We present the high-irradiance photothermal treatment using the dual-wavelengths as a novel method to regulate venous and arterial bleeding and potentially as a rapid noncontact hemostasis option to mitigate the risk associated with significant blood loss.

Fibrosis is a prevalent problem that pathologically accompanies chronic inflammatory diseases. Despite the availability of various fibrosis treatments, therapeutic efficacy must be further improved to achieve better clinical outcomes. The purpose of this study is to develop a novel treatment by combining phloroglucinol (PHL) with photobiomodulation (PBM) to prevent skin fibrosis. In in vitro, 635 nm PBM at 8 J/cm2 significantly reduced TNF-alpha levels, and 100 μg/ml of PHL suppressed the expression of α-smooth muscle actin and type I collagen due to the downregulation of SMAD 2/3 and MAPK signaling pathways. The 1470 nm laser light created the initial wound (97.1 mm2), leading to scar formation after complete wound closure (21 days) on rodent skin. In comparison to other groups, the dual treatment accelerated wound closure and achieved rapid and complete healing in 17 days. Histological analysis presented the reduced fibrotic scar and collagen deposition in the dual treatment group. PHL-combined PBM treatment enhanced the anti-inflammatory effect by 36% in comparison to single treatment groups. Overall, the proposed combined treatment promoted wound healing and enhanced anti-inflammatory and anti-fibrotic effects in the overexpressed in vitro and in vivo models.

Hybrid catalysts consisting of metal nanoparticles on a metal oxide support have emerged as a new class of catalysts that can improve various electrocatalytic reactions, but the origin of the improved performance is still unclear. Here we demonstrate that rationally designed hybrid catalysts through the in situ exsolution process of metallic nanoparticles on a B-site Ni-substituted lead ruthenate pyrochlore oxide improve both oxygen evolution reaction and hydrogen evolution reaction activity. A combination of operando X-ray absorption spectroscopy measurements and density functional theory calculations reveals that the generated oxygen and cation vacancies in the pyrochlore oxide support during the in situ exsolution process can decrease the charge-transfer energy, thereby facilitating charge transfer between exsolved metal nanoparticles–oxide support as well as hybrid catalyst–electrolyte. These findings establish a structure–property relationship of complicated hybrid catalysts for efficient water splitting, suggesting a new strategy in designing various hybrid catalysts for other electrochemical reactions.

Simulation involving interaction with deformable objects often causes stability problems because a slowly updated force generates additional energy to the human user. This paper proposes a stable and transparent haptic rendering for simulation involving interaction between a rigid tool and deformable objects. This method computes visual and haptic feedback in the simulation and haptic feedback loops, respectively. A local stiffness matrix consisting of points around contact points is constructed based on collision detection between a virtual tool and a deformable object in the simulation loop. The haptic feedback is then computed at a higher update rate in the haptic feedback loop using the local stiffness matrix. Equivalent springs computed by using the equivalent stiffness energy are added to the boundary of the local stiffness matrix to minimize errors in the rendered force. The proposed method is compared with the virtual coupling widely used in simulation involving interaction with deformable objects. The proposed method reduces the x -, y -, and z -axis maximum force errors by up to 52%, 80%, and 70%, respectively, compared to the virtual coupling in the simulation involving interaction with the Stanford bunny object consisting of 2087 points and 9997 tetrahedrons.

With the lightening of the mobile devices, thinning of electrolytic copper foil, which is mainly used as an anode collection of lithium secondary batteries, is needed. As the copper foil becomes ultrathin, mechanical properties such as deterioration of elongation rate and tear phenomenon are occurring, which is closely related to microstructure. However, there is a problem that it is not easy to prepare and observe specimens in the analysis of the microstructure of ultrathin copper foil. In this study, electron backscatter diffraction (EBSD) specimens were fabricated using only mechanical polishing to analyze the microstructure of 8 μm thick electrolytic copper foil in plane view. In addition, EBSD maps and transmission electron microscopy (TEM) images were compared and analyzed to find the optimal cleanup technique for properly correcting errors in EBSD maps.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO subgroup I-like proteins, which contain an AA15 LPMO catalytic domain and a conserved C-terminal cysteine-rich motif, two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen for study. RNAi for the T. castaneum protein, TcLPMO1, caused molting arrest at all developmental stages, whereas RNAi of the L. migratoria protein, LmLPMO1, prevented only adult eclosion. In both species, LPMO1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO1-like protein from Ostrinia furnacalis (rOfLPMO1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal for the first time the physiological importance of catalytically active LPMO1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of chitin turnover during molting.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO15 subgroup I-like proteins (LPMO15-1s), two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen. Depletion by RNAi of T. castaneum TcLPMO15-1 caused molting arrest at all developmental stages, whereas depletion of the L. migratoria LmLPMO15-1, prevented only adult eclosion. In both species, LPMO15-1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of the chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO15-1-like protein from Ostrinia furnacalis (rOfLPMO15-1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal the physiological importance of catalytically active LPMO15-1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of cuticular chitin turnover during molting.

Transition metal single atom catalysts have recently emerged in acid oxygen evolution reactions (OER) due to their maximum atomic efficiency and high durability. Herein, we report a 3d orbital level rearrangement in square planar symmetry according to the ligand type of a cobalt single atom catalyst. We fabricate cobalt single atom catalyst supported on pyrrole type nitrogen doped crumpled graphene (Pyrrolic CoN4-CG) for acidic OER and it shows orbital rearrangement phenomenon because of their longer Co-N bond distance than pyridine type CoN4 sites. When pyrrole type nitrogen is introduced as a ligand of a cobalt single atom catalyst, the degree of oxidation during OER reaction is much greater than when pyridine type nitrogen ligand is introduced, which is confirmed by Operando X-ray absorption spectroscopy measurements. In addition, the reduction of OH- adsorption energy according to the orbital level rearrangement of Pyrrolic CoN4 and the change in the rate determination step are revealed by density functional theory calculations.

van der Waals heterostructures composed of two-dimensional materials vertically stacked have been extensively studied to develop various multifunctional devices. Here, we report WSe

The sodium-air (Na–air) batteries are considered as a new promising energy storage devices due to their 1683 W h kg−1 of high theoretical specific energy density. However, these outstanding theoretical energy density performances cannot be achieved because undesirable sluggish oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) reaction kinetics on the air cathode side causes the high overpotential gap and low round-trip efficiencies during charge-discharge process. Therefore, the development of highly active bifunctional oxygen electrocatalysts is the key strategy to obtain the low overpotential gap with high energy density performance of Na-air batteries. In this work, a novel single crystalline thallium ruthenium oxide (Tl2Ru2O7) with pyrochlore structure was firstly revealed as an effective bifunctional electrocatalyst. Moreover, in order to enhance the surface chemical reactivity of Tl2Ru2O7, the surface of Tl2Ru2O7 is functionalized by using the dihydrogen phosphate ion (P-Tl2Ru2O7) for achieving the effective and rapid charge transfer behavior. The superior bifunctional catalytic activity of P-Tl2Ru2O7 can be explained by the degree of covalency of Ru-O bonds in Tl2Ru2O7 and enhanced covalent character by functionalized dihydrogen phosphate ion, which can afford favorable oxidation nature to Tl and Ru ions.

The sodium-air (Na-air) batteries are spotlighted as state-of-the-art electrical energy storage system, because of their high sodium-ion conductivity and specific energy density performance. However, the undesirable sluggish oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) kinetics limit the practical production of rechargeable Na-air batteries. Therefore, it is essential to develop highly effective bifunctional electrocatalysts for OER and ORR. Although the pyrochlore oxides (A2B2O7) exhibits great potential for highly-active bifunctional electrocatalyst, the lack of studies regarding to A-site cations have hindered the development of new pyrochlore catalysts with comprehensive understanding of catalytic activity. In this work, we report the use of a novel nanocrystalline bismuth ruthenate pyrochlore oxide (Bi2Ru2O7) as an effective oxygen electrocatalyst by using the favorable oxidation nature of Bi and Ru ions in Bi2Ru2O7. Further, the oxidized cations can donate the electrons to the surface and inner layers, providing the low-resistance pathway during OER and ORR. Finally, the bifunctional electrocatalytic activities of Bi2Ru2O7 are successfully translated to a practical device, an aqueous Na-air battery, for the first time.

We developed a guinea fowl jumping robot with a one-axis momentum wheel mechanism with a passive hallux model. The Guinea fowl jumping robot was able to perform stable vertical jumping due to the linkage structure designed as a passive hallux model. Furthermore, we used the one-axis momentum wheel mechanism in the jumping robot for making the compact balance control mechanism that can control the body angle of the robot. Through the experiment, the conventional jumping robot uses the inertial tail to adjust the body angle in the air for stable landing and jumping. However, in the case of an inertial tail, it has a large volume and has a disadvantage in that stability is highly reduced when it collides with obstacles due to the shape of the inertial tail. Moreover, we performed a theoretical analysis, simulation, and experiment to verify the performance of the momentum wheel mechanism, and we confirmed that the passive hallux structure contributed to the jumping stability. Besides, we proved that the momentum wheel could adequately land on the ground by adjusting the body angle after vertical jumping. In addition, we demonstrated that the stability of the momentum wheel is higher than the inertial tail through collision simulation.

Flat heat pipe, vapor chamber, thermal ground plane, and heat spreader have been emerging topics for various thermal applications such as electric battery packs and high-power computer chips. In this study, computational fluid dynamics is used to model the effective thermal conductivity of a vapor chamber and thermal ground plane. From various literature, simulation conditions are obtained for different flat heat pipe geometries. With the commercial code Fluent (Ansys Inc.), 4,800 cases have been used to examine the spreading thermal resistance tendencies for the different heat sink areas, heat source area, thickness, and heat transfer coefficient. In conclusion, the effective thermal conductivity increases when the thickness decreases or the heat sink area becomes greater with the same spreading thermal resistance value. In particular, the modified model of spreading thermal resistance is proposed for a better accuracy targeting various effective thermal conductivity, based on the original analytical model. A good agreement with a better accuracy is found between the model and the numerical results. This study will be able to provide the thermal system guideline for flat heat pipes.

Ir and its oxide are the only available oxygen evolution reaction (OER) electrocatalysts with reasonably high activity and stability for commercial proton-exchange membrane electrolyzers. However, the establishment of structure–performance relationships for the design of better Ir-based electrocatalysts is hindered by their uncontrolled surface reconstruction during OER in acidic media. Herein, we monitor the structural evolution of two model Ir nanocrystals (one with a flat surface enclosed by (100) facets and the other with a concave surface containing numerous high-index planes) under acidic OER conditions. Operando X-ray absorption spectroscopy measurements reveal that the promotion of surface IrOx formation during the OER by the concave Ir surface with high-index planes results in a gradual OER activity increase, while a decrease in activity and limited oxide formation are observed for the flat Ir surface. After the activation process, the Ir concave surface exhibits ~ 10 times higher activity than the flat surface. Density functional theory computations reveal that Ir high-index surfaces are thermodynamically preferred for the adsorption of oxygen atoms and the formation of surface oxides under OER conditions. Thus, our work establishes a structure–performance relationship for Ir nanocrystals under operating conditions, providing new principles for the design of nanoscale OER electrocatalysts.

Resonant elastic X-ray scattering has been widely employed for exploring complex electronic ordering phenomena, like charge, spin, and orbital order, in particular in strongly correlated electronic systems. In addition, recent developments of pump-probe X-ray scattering allow us to expand the investigation of the temporal dynamics of such orders. Here, we introduce a new time-resolved Resonant Soft X-ray Scattering (tr-RSXS) endstation developed at the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL). This endstation has an optical laser (wavelength of 800 nm plus harmonics) as the pump source. Based on the commissioning results, the tr-RSXS at PAL-XFEL can deliver a soft X-ray probe (400-1300 eV) with a time resolution about ~100 fs without jitter correction. As an example, the temporal dynamics of a charge density wave on a high-temperature cuprate superconductor is demonstrated., 7 figures, 2 tables

Here we present our study on an impact print-type hot embossing process which can create dot patterns with various designs, widths, and depths in real time on polymer film. In addition, we implemented a control system for the on-off motion and position of the impact header to engrave different dot patterns. We performed dot patterning on various polymer films, such as polyester (PET) film, polymethyl methacrylate (PMMA) film, and polyvinyl chloride (PVC) film. The dot patterns were measured using a confocal microscope, and we confirmed that the impact print-type hot embossing process produces fewer errors during the dot patterning process. As a result, the impact print-type hot embossing process is found to be suitable for engraving dot patterns on different types of polymer films. In addition, unlike the conventional hot embossing process, this process does not use an embossing stamp. Therefore, the process is simple and can create dot patterns in real time, presenting unique advantages for mass production and small-quantity batch production.

SUMMARYPrevious researches on analysis of stability of haptic simulation largely assume that the virtual environment is passive. But the virtual environment can become non-passive due to various reasons including discretization errors and interaction dynamics between virtual tools and objects. This paper provides an analysis of the stability and performance of the haptic simulation involving non-passive virtual environment. The dynamic interaction between the virtual tools and the objects is modeled using the two-port networks. The analysis is carried out using a velocity and force mapping matrix for six-DOF simulation. New stability condition resulting from the analysis is applied to an example simulation of a one-DOF virtual wall. Maximum stiffness satisfying the stability condition established in the previous literature, and the proposed condition is compared with the maximum stiffness experimentally determined with various time steps. The newly proposed stability condition manifests less standard deviation of errors than the widely applied absolute stability condition.

The third-generation synchrotron radiation accelerator has been providing beams to users since 1995 and have been made to upgrade the performances of the accelerators and the experimental devices. For that reason, the PLS-II was started in 2009 as a three-year project. An important feature is the extension of the ID (insertion device) beamline and the efficient placement of the storage ring magnet structure. The overall structure of the beamline as well as the length and structure of the front end had to be changed to expand the ID beamline. Also, the safety of many vacuum parts that would be exposed to the large heat due to the increase in the beam energy was firstly considered in the design, and an analysis was performed in parallel. This paper describes the overall structure of the front end, including the design and analysis of the vacuum components in the Pohang Light Source(PLS)-II beamline.

Nitrogen and sulfur co-doped mesoporous carbon sphere (NSMCS) was prepared as a metal-free catalyst by an economical and facile pyrolysis process. The mesoporous carbon spheres were derived from sodium carboxymethyl cellulose as the carbon source and the nitrogen and sulfur dopants were derived from urea and p-benzenedithiol, respectively. The doping level and chemical states of nitrogen and sulfur in the prepared NSMCS can be easily adjusted by controlling the pyrolysis temperature. The NSMCS pyrolyzed at 900 °C (NSMCS-900) exhibited higher oxygen reduction reaction activity than the mesoporous carbon sphere doped solely with nitrogen or sulfur, due to the synergistic effect of co-doping. Among all the NSMCS samples, NSMCS-900 exhibited excellent ORR catalytic activity owing to the presence of a highly active site, consisting of pyridinic N, graphitic N, and thiophene S. Remarkably, the NSMCS-900 catalyst was comparable with commercial Pt/C, in terms of the onset and the half-wave potentials and showed better durability than Pt/C for ORR in an alkaline electrolyte. The approach demonstrated in this work could be used to prepare promising metal-free electrocatalysts for application in energy conversion and storage.

Graphitic carbon nitride/mesoporous carbon sphere composites were successfully synthesized using a simple, three-step treatment, and the effects of the mesoporous carbon sphere (MPCS) content on the electrochemical properties of the composites were studied. The MPCSs were homogeneously captured and dispersed on the prepared graphitic carbon nitride (GCN), forming a GCN/MPCS nanocomposite structure. These composite materials exhibited better electrochemical properties than previously reported electric double-layer capacitor (EDLC) materials, such as carbon nanotubes, graphene, activated carbon, and carbon spheres. The addition of a small amount of mesoporous carbon spheres, typically 1:2 by weight (GCN/MPCS), to form GCN/MPCS(2) resulted in an excellent specific charge capacity of 352.44 F g−1 at a scan rate of 5 mV s−1. These results indicate the potential of the composite for the development of highly capacitive energy storage devices with practical applications.

BACKGROUND AND OBJECTIVE Hypertrophic scar (HTS) results from a connective tissue reaction to trauma, inflammation, surgery, or burn on skin. In spite of various techniques for wound generation, the degree of scar in animal models after healing is still unpredictable and less reproducible. The objective of the current study was to identify the appropriate method to create the maximal HTS tissue in a reliable manner by comparing three different methods in vivo. MATERIALS AND METHODS A 27 ICR mice were tested for the in vivo evaluations. Three different methods were applied to develop wounds on the back of each mice for quantitative evaluations on collagen formation: Group 1 (thermal burn), Group 2 (chemical burn), and Group 3 (physical punch). After injury, each lesion was photographed to examine physical variations in the wound areas. Histological analysis was conducted on days 0, 7, and 28 to assess the extent of the injury in the tissue and to quantitatively compare the amount of collagen formation after wound healing. RESULTS Compared with Groups 1 and 3, Group 2 demonstrated the largest wound area that gradually decreased with healing time. However, the minimal axial damage (along tissue depth) occurred to Group 2 at day 0 (183.7 ± 28.9, 38.1 ± 9.2, and 296.0 ± 81.7 µm for Groups 1, 2, and 3, respectively). After 28 days, all the groups showed the complete healing and accompanied a significant increase in the number of fibroblast and collagen generation with well-oriented and denser collagen fibers, in comparison with normal skin. Group 2 yielded twice thicker skin (both epidermis and dermis) than the other groups (970.8 ± 108.8 µm for Group 2 vs. 381.5 ± 30.8 µm for Group 1 and 442.9 ± 56.3 µm for Group 3; P

MgCo2O4 nanoneedles were introduced on the surface of micro and mesoporous silicon carbide flakes (SiCF) to synthesize a supercapacitor with high capacitive performance, made of hybrid electrode materials. Based on the synergistic effect between electric double layer capacitive contributions of SiCF and faradic reaction of MgCo2O4, the SiCF/MgCo2O4 electrode shows outstanding energy storage performance, exhibiting a 310.02 C g−1 of specific stored charge capacity at 5 mV s−1 with high capacity retention ratio over wide range of scan rates (83.2% at 500 mV s−1). Furthermore, in conjunction with a capacitive SiCF negative electrode in a quasi-solid-state PVA-KOH KI gel electrolyte, it resulted in a unique redox-active flexible solid-state asymmetric supercapacitor device. It delivers outstanding capacitive performance (specific stored charge capacity of 185.88 C g−1 at 5 mV s−1), with maximum energy density of 41.308 Wh kg−1 at 464.72 W kg−1 of power density, surpassing many recently reported flexible supercapacitors. Moreover, the ability to operate 3-V green light-emitting diodes (LED) at bending state also indicates its possibility for practical application. Therefore, these novel electrode materials with unique redox-active solid state electrolyte may find promising applications in flexible energy storage devices in future.

Na–air batteries have received significant attention as possible candidates for alternative battery systems due to their high specific energy density (1683 W h kg−1). However, the undesirable sluggish kinetics of the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) limit the practicality of the production of rechargeable Na–air batteries. Recently, pyrochlore oxides (A2B2O7) have received great attention as effective bifunctional electrocatalysts. However, the comprehensive understanding of catalytic activity with the development of new pyrochlore catalysts is unsatisfactory due to the limited use of B-site cations. Here, we report the use of a novel nanocrystalline bismuth rhodium oxide (Bi2Rh2O6.8) crystal with a pyrochlore structure as a bifunctional electrocatalyst. Moreover, the surface of Bi2Rh2O6.8 was modified via phosphate-ion functionalization (P-Bi2Rh2O6.8) to enhance its surface chemical reactivity, resulting in fast and efficient charge transfer with high ORR and OER activities. During electrocatalysis, the functionalized H2PO4− ion can not only significantly enhance the surface reactivity for a fast and efficient electron/charge-transfer reaction but also facilitate the oxidation of Bi and Rh ions and boost the electron donation by improving the electron transport. Finally, the first successful translation of the bifunctional electrocatalytic activities of P-Bi2Rh2O6.8 to a practical device, an aqueous Na–air battery, was demonstrated.

The unique designed and their tunable intrinsic active sites for OER have a key role in alternating the noble metal (IrO2). Herein, we fabricated Co-Ni-N-S-O nanocage through a simple self-catalytic process. The outstanding OER performance is based on the rich defect sites and oxygen vacancies in the amorphous phase with abundant surface area attributed to the hollow nanocage structure, and the ‘ensemble effect’ caused by N and S doping. The high intrinsic active surface area of Co-Ni-N-S-O was confirmed by double-layer capacitance (Cdl: 5.39 mF/cm2), and the ‘ensemble effect’ was determined through XPS and XAS analysis. The metal centers were located to a higher oxidation state, resulting the advantageous for the formation of OER intermediates (*OOH), as proved by operando XAS analysis. The Co-Ni-N-S-O catalyst provides a valuable strategy to design electrocatalysts of high efficiency and expand the applications of catalysts based on amorphous metal oxides.

Augmented reality medical training simulators can provide a realistic and immersive experience by overlapping the virtual scene on to the real world. Latency in augmented reality (AR) medical training simulators is an important issue as it can lead to motion sickness for users. This paper proposes a framework that can achieve real-time rendering of the 3D scene aligned to the real world using a head-mounted display (HMD). Model deformation in the 3D scene is categorised into local deformation derived from user interaction and global deformation determined by the simulation scenario. Target shapes are predefined by a simulation scenario, and control points are placed to embed the predefined shapes. Free-form deformation (FFD) is applied to multiple shapes to efficiently transfer the simulated model to the HMD. Global deformation is computed by blending a mapping matrix of each FFD with an assigned weighting value. The local and global deformation are then transferred through the control points updated from a deformed surface mesh and its corresponding weighting value. The proposed framework is verified in terms of latency caused by data transmission and the accuracy of a transmitted surface mesh in a vaginal examination (VE) training simulation. The average latency is reduced to 7 ms, less than the latency causing motion sickness in virtual reality simulations. The maximum relative error is less than 3%. Our framework allows seamless rendering of a virtual scene to the real world with substantially reduced latency and without the need for an external tracking system.

The 3d transition metal-based catalysts have emerged as prospective electrocatalysts for the oxygen evolution reaction (OER) owing to the wide availability of transition metals in the Earth’s crust, as well as the low cost and long lifetime of the catalysts. However, their moderate activity for the OER is a challenge for commercial applications. In this study, a heterostructure (W@Ni(OH)2/CC) composed of Ni(OH)2 nanosheets and tungsten nanoparticles was successfully synthesized on a conductive carbon cloth to overcome the problem of deficient catalytic activity. The constructed heterointerface and the two-dimensional (2D) nanosheet morphology of the catalyst can accelerate the charge transfer, OER kinetics, and the ion/gas transport. In addition, interfacial electronic structure optimization was investigated to facilitate the formation of oxyhydroxide intermediates on the catalyst surface, which enhances the overall OER performance. This paper provides a thorough explanation on the role of modified electronic configuration in the heterostructures and proposes a new path to synthesize these heterostructures.

The photon beam position monitor (PBPM) plays a critically important role in the accurate monitoring of the beam position. W (Wire)-PBPMs are installed at the front end and photon transfer line (PTL) of the diagnostic beamline and detect the change of position and angle of the beam orbit applied to the beamline. It provides beam stability and position data in real time, which can be used in feedback system with BPM in storage-ring. Also it provides beam profile, which makes it possible to figure out the specifications of beam. With two W-PBPMs, the angle information of beam could be acquired and the results coupled with beam profile are used with orbit correction. The W-PBPM has been designed and installed in the diagnostic beamline at Pohang Light Source. Herein the details of the design, analysis and performance for the W-PBPM will be reported.

Micro- and mesoporous silicon carbide (SiC)/ferroferric oxide (Fe 3 O 4 ) composites (SiC/Fe 3 O 4 ) were prepared (to develop novel supercapacitor electrode materials) via chemical deposition of Fe 3 O 4 on SiC surfaces by chemical reduction of an Fe precursor. Based on the synergistic contributions between the electric double layer capacitive contribution of SiC and the pseudocapacitive contribution of Fe 3 O 4 , the SiC/Fe 3 O 4 electrode exhibits outstanding charge storage capacity, exhibiting a specific capacitance of 423.2 F g −1 at 5 mV s −1 with high capacitance retention ratio over a wide range of scan rates (81.8% at 500 mV s −1 ). In conjunction with a capacitive SiC positive electrode in a quasi-solid-state PVA-KOH- p -nitroaniline (PVA-KOH-PNA) gel electrolyte, it resulted in a unique redox-active flexible solid-state asymmetric supercapacitor device. Due to the vigorous redox reactions of Fe 3 O 4 nanoparticles and the p -nitroaniline redox active electrolyte, the device delivers outstanding capacitive performance (specific capacitance of 97.6 F g −1 at 5 mV s −1 ) with maximum energy density of 48.94 Wh kg −1 at power density of 463.64 W kg −1 , surpassing many recently reported flexible supercapacitors. Therefore, these novel electrode materials with unique redox-active solid-state electrolytes may find promising applications in flexible energy storage devices.

Ni(OH)2 nanoparticles were decorated on mesoporous carbon spheres (MPCS) using a simple hard template method. The MPCS were derived from sodium carboxymethyl cellulose. As-prepared MPCS/Ni(OH)2 nanocomposites were used as electrode materials for supercapacitors. These composites exhibited better electrochemical properties than a pristine mesoporous carbon sphere owing to the synergistic effect. However, the increase in Ni(OH)2 is not proportional to the electrochemical performance improvement. The addition of an optimal amount of Ni(OH)2, typically 1:20 by weight (MPCS:NiCl2·6H2O), showed an excellent specific capacitance of 1338.296 F g−1 at a scan rate of 5 mV s−1. These encouraging results indicate excellent potential for the development of highly capacitive energy storage devices for practical applications.

MgCo 2 O 4 nanoneedles were deposited onto micro and mesoporous silicon carbide flakes (SiCF) to synthesize hybrid electrode materials with high capacitive performance for use as supercapacitors. These SiCF/MgCo 2 O 4 electrodes were fabricated at different MgCo 2 O 4 feeding ratios to determine the optimal MgCo 2 O 4 amount for both total surface area coverage and a suitable redox reaction rate by maximizing the synergy between the electric double layer capacitive effects of SiCF and the Faradic reaction of MgCo 2 O 4 nanoneedles. The SiCF/MgCo 2 O 4 electrode formed at a MgCo 2 O 4 /SiCF feeding ratio of 1.8:1 (SiCF/MgCo 2 O 4 (1.8)) had a specific surface area of 1069 m 2 g −1 . This surface featured the highest specific stored charge capacity of 310.02 C g -1 at a scan rate of 5 mV s -1 with 83.2% rate performance when the scan rate was increased from 5 to 500 mV s -1 in a 1 M KOH electrolyte. The outstanding electrochemical performance of the SiCF/MgCo 2 O 4 (1.8) electrode can be attributed to the ideal electrode material design, considering both the electric double-layer capacitive contribution of SiCF and the battery-type electrochemical behavior of the MgCo 2 O 4 nanoneedles on the SiCF surface. For high capacity electrode materials, this hybrid material strategy introduces possibilities for combinations of porous silicon carbide with other battery-type binary metal oxide materials.