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Novel two-dimensional semiconductor crystals can exhibit diverse physical properties beyond their inherent semiconducting attributes, making their pursuit paramount. Memristive properties, as exemplars of these attributes, are predominantly manifested in wide-bandgap materials. However, simultaneously harnessing semiconductor properties alongside memristive characteristics to produce memtransistors is challenging. Herein we prepared a class of semiconducting III–V-derived van der Waals crystals, specifically the HxA1–xBX form, exhibiting memristive characteristics. To identify candidates for the material synthesis, we conducted a systematic high-throughput screening, leading us to 44 prospective III–V candidates; of these, we successfully synthesized ten, including nitrides, phosphides, arsenides and antimonides. These materials exhibited intriguing characteristics such as electrochemical polarization and memristive phenomena while retaining their semiconductive attributes. We demonstrated the gate-tunable synaptic and logic functions within single-gate memtransistors, capitalizing on the synergistic interplay between the semiconducting and memristive properties of our two-dimensional crystals. Our approach guides the discovery of van der Waals materials with unique properties from unconventional crystal symmetries.

Monoclinic Fe3Se4 was synthesized using a ceramic method. Mössbauer spectroscopy and density functional theory were used to investigate the physical origins of its ferrimagnetism and high coercivity. At 78 K, 12 Mössbauer absorption lines were observed. These lines are composed of two subspectra, A and B, corresponding to Fe atoms at the 2a and 4i sites, respectively. At 320 K, the Mössbauer spectrum collapsed, indicating a transition from a ferrimagnetic to a paramagnetic state. This temperature is close to the Curie temperature (TC) of 331 or 315 K reported in the literature. The analysis of local structural symmetry confirmed that the Fe atoms in the 2a sites are more symmetrically coordinated with neighboring Se atoms than those in the 4i sites. Therefore, the Fe atoms in the 2a sites exhibit a higher hyperfine magnetic field (HMF) of 225 kOe and a weaker quadrupole splitting (QS) of 0.17 mm/s than the Fe atoms in the 4i sites, which exhibit an HMF of 105 kOe and a QS of 0.55 mm/s. Our density functional study confirmed that Fe3Se4 exhibits ferrimagnetic behavior, with a magnetic moment of 4.48 µB/u.c. and a TC of 354 K. Fe3Se4 shows a high magnetocrystalline anisotropy constant (Ku) of 0.9 × 106 erg/cm3. This high Ku value is attributed to the Fe atoms at the 4i sites. It is suggested that the high coercivity of Fe3Se4, as reported in the literature, is due to the distorted 4i site, which experiences the Jahn–Teller effect.

Purpose: Rebamipide (RBM) is known to have a specific absorption window in the upper GI tract. However, there have been no in vivo studies reporting the regional absorption of RBM, which may lead to misjudgment in formulation development considering the many other physiological factors involved in oral absorption. Therefore, this study aimed to assess the regional absorption of RBM. Methods: Barium sulfate was incorporated into RBM-sustained release (SR) tablets as a radiopaque marker and the location of RBM-SR tablets was monitored using X-ray imaging after oral administration of RBM-SR tablets in Beagle dogs. Results: Based on the gastric residence time (GRT) of RBM-SR tablets, dogs were divided into two groups: GRTlowfor 0.25 and 1.5 h and GRThighfor 3 and 5 h. GRThighhad significantly delayed time to reach peak plasma concentration (Tmax), longer mean residence time (MRT), and higher area under the plasma concentration–time curve from time zero to the last observation time point (AUClast) than GRTlow, which indicates the presence of an absorption window in the upper GI tract. Conclusion: This study, for the first time, reports on the regional absorption of RBM. The findings of this study may be useful for developing RBM-SR formulations.

MG1113 is a human monoclonal antibody of tissue factor pathway inhibitor (TFPI) under development for prophylaxis for hemophilia patients with or without inhibitors against factor VIII products, which have been used for the treatment of hemophilia. Because TFPI is a negative regulator in the extrinsic coagulation pathway, neutralization of TFPI function by MG1113 can potentially increase coagulation activity by bypassing the intrinsic coagulation pathway, which factor VIII activates. This study aims to determine the correlation between pharmacokinetics (PK) and pharmacodynamics (PD) after administering MG1113 to monkeys and to predict the PK and PD of MG1113 in humans by the Target‐Mediated Drug Disposition (TMDD) model using the results from monkeys. The PK profile of MG1113 and the PD effect on the free TFPI level were evaluated after intravenous (IV) and subcutaneous (SC) administrations of MG1113 (2.5, 5, and 10 mg/kg) to male cynomolgus monkeys. After setting up the PK/PD model on monkeys, PK parameters on humans were calculated using allometric scaling, and then clinically effective doses were predicted applying the TMDD model. MG1113 showed nonlinear PK after both IV and SC administrations at the dosing range from 2.5 to10 mg/kg. The concentrations of MG1113 versus TFPI could be characterized a dose‐response relationship using a TMDD model. The TMDD modeling and simulation built in this study were used to simulate various dosage regimens of MG1113 to apply to the first‐in‐human study design, and moreover expected to be referred to establish the dose for further clinical trials.

MG1113 is a human monoclonal antibody of tissue factor pathway inhibitor (TFPI) under development for prophylaxis for hemophilia patients with or without inhibitors against factor VIII products, which have been used for the treatment of hemophilia. Because TFPI is a negative regulator in the extrinsic coagulation pathway, neutralization of TFPI function by MG1113 can potentially increase coagulation activity by bypassing the intrinsic coagulation pathway, which factor VIII activates.

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been extensively studied. Among them, vanadium dichalcogenides, a unique metallic family of the TMDCs, have been considered as potential room temperature ferromagnetic materials at the monolayer scale. However, further progress has been hampered by the difficulties growing monolayer and the challenges making high-quality single crystalline VSe2, free from artificial factors. Here, we report high-quality octahedral 1T-VSe2single crystals grown by chemical vapor transport. Spectroscopic analyses identified that as-grown VSe2crystals were a single phase of VSe2and highly oriented along the (00l) plane. High-resolution scanning transmission electron microscopy verified that as-grown VSe2crystals not only had single crystalline nature, the octahedral 1T phase, and AAA stacking order in atomistic real space, but also supported valuable lattice information that differed from the predicted values of the previous calculation model. Mechanical exfoliation allowed our VSe2crystals to turn into large-sized VSe2flakes with various thicknesses. With in-depth structural analyses, our findings provide insight into further research of the fundamental calculation model and the crystallographic tailoring for intrinsic room-temperature 2D ferromagnetic materials.

Aim. It is essential to understand the extent to which job characteristics impact work-related musculoskeletal disorders (WMSDs), and to calculate the probability that an employee will suffer from a musculoskeletal disorder given their working conditions. The objective of this research is to identify the relationships between WMSDs and working characteristics, by developing a Bayesian network (BN) model to calculate the probability that an employee suffers from a musculoskeletal disorder. Methods. A conceptual model was constructed based on a BN. This was then statistically tested and corrected to establish a BN model. Results. Experiments verified that the BN model achieves a better diagnostic performance than artificial neural network, support vector machine and decision tree approaches, and is robust in diagnosing WMSDs given working characteristics. Conclusion. It was verified that working characteristics, such as working hours and pace, impact the incidence rate of WMSDs, and a BN model was developed to probabilistically diagnose WMSDs.

Post-synthesis engineering methods that employ oriented attachment to precisely control the size and dimensionality (0D/1D/2D) of as-synthesized CsPbBr3nanocrystals (NCs) are demonstrated. We investigated the chemical effects of the properties of polar solvents, including their immiscibility, polarity, and boiling point, on the surfaces of NCs, as well as their effect on the structural and optical properties of NCs. Appropriate exploitation of the solvent properties made it possible to use a polar solvent to mildly affect the NCs indirectly such that they discarded their ligands and became attached to proximal NCs without being destroyed. Based on our observations, we developed a method whereby a solution of the NCs in a non-polar solvent is mixed with a polar solvent to form an immiscible phase to induce epitaxial growth of CsPbBr3NCs. The method enables the size of NCs to be easily regulated from 5 to 50 nm by controlling the engineering time. Taking advantage of the minimal effect of a mild solvent, we also developed a self-assembly method that operates at the liquid–air interface to systematically control the dimensionality. At this interface, the NCs self-assemble in the horizontal direction and grow into micron-sized, single-crystalline, defect-free nanowires (1D) and nanoplates (2D) viaoriented attachment. Finally, we discuss the origin of the non-destructive oriented attachment phenomenon and the surface chemistry of a perovskite NC using density functional theory (DFT) simulations and a proposed model system.

Introduction. The objective of this study was to measure the effect of hand postures and object properties on nine forearm muscle activities and their contribution using surface electromyography. Methods. Ten male university students participated in the experiment. The objects used were cylindrical and rectangular, with lengths and weights of 2, 4, 6 and 8 cm and 400, 800, 1400 and 1800 g. The experimenter told the participant to pick up the object using a particular hand posture, lift the object to approximately shoulder height and maintain this posture for 3 s. Results. The hand posture, object size and object weight greatly influenced the muscle activities, but the object shape did not. Pinching with two or three fingers yielded the greatest muscle activities with the 8-cm, 1800-g object. The extensor pollicis longus and flexor pollicis longus muscles exhibited the highest submaximal voluntary contraction. Conclusion. This study provides basic information about the specific activities of the forearm muscles and the effects of the hand postures and object properties on those activities.

Two-dimensional Ruddlesden–Popper series are an excellent system for tuning physical properties of the perovskite by controlling the layer number (n). For instance, bandgap and exciton binding energies of the series gradually increase upon reducing nvia enhanced quantum and dielectric confinements. Here, we present findings that challenge the anticipated trend in electron–hole exchange interaction within (BA)2MAn–1PbnBr3n+1(n= 1–3), which causes spin-dependent exciton level splitting into bright and dark states, where the latter is partially visible near the surface of the Br-based two-dimensional Ruddlesden–Popper series. Contrary to expectations, the smallest gap between bright and dark exciton levels is observed from n= 2 at 10 K. This anomaly results in the strongest biexciton binding between two dark excitons occurring at n= 2, rather than at n= 1 as initially hypothesized. The observed anomaly arises from a phase transition induced by octahedral tilting occurring only for n= 2 near 100 K as confirmed by temperature-dependent optical and X-ray diffraction measurements. Our results show that Coulomb interaction need not vary gradually with n, which can impact the optoelectronic properties of the Ruddlesden–Popper series.

This study presents a preliminary investigation of the application of MAPbI3perovskite solar cells (PSCs) as dosimeters for space and medical purposes. Specifically, it explores the effects of 6 MeV electron beam exposure on the performance and degradation mechanisms of PSC devices. The study also employs crystallographic, optical, and simulation-based analyzes to gain insights into the degradation process. The findings of this research lay the groundwork for the development of an advanced radiation detection structure, combining a scintillator with a photocounting PSC device, as a potential replacement for existing silicon photomultipliers in the future. The PSC devices exhibit an initial power conversion efficiency of approximately 14%. However, under electron fluences ranging from 3 to 21 kGy, a gradual degradation is observed, characterized by a decline in open-circuit voltage and short-circuit current. Beyond the 9 kGy threshold, the device performance deteriorates significantly, with a 52% decrease compared with the initial performance, which is primarily attributed to a decrease in the fill factor. Through X-ray diffraction, time-resolved photoluminescence, and density functional theory simulations, the research uncovers that continuous electron beam exposure induces the formation of crystallographic defects and shallow traps, leading to the gradual deterioration of device performance postirradiation.

The cross-sections of natTi(p,x) reactions were measured up to 50 MeV by using off-line γ-ray spectrometry and stacked-foil activation technique. The activation experiment was conducted using 57 MeV proton beams from the proton accelerator at the Korea Multi-purpose Accelerator Complex (KOMAC). The natNi(p,x)57Ni reaction was employed to monitor the proton beam flux. The activity of irradiated sample was measured using a high purity germanium (HPGe) detector, and the measured cross-sections were compared with literature data and the TENDL-2023 library. The present work generally matched well with the literature data. The cross-sections for 43,44,47Sc produced through the natTi(p,x) reactions can be used for medical isotopes production, while natTi(p,x)48V reaction can be utilized for proton monitoring reaction.

This study explored whether complete electrical isolation of the left atrial (LA) posterior wall improves the rhythm outcome of catheter ablation of persistent atrial fibrillation (AF).

The exchange interaction governs static and dynamic magnetism. This fundamental interaction comes in two flavours—symmetric and antisymmetric. The symmetric interaction leads to ferro- and antiferromagnetism, and the antisymmetric interaction has attracted significant interest owing to its major role in promoting topologically non-trivial spin textures that promise fast, energy-efficient devices. So far, the antisymmetric exchange interaction has been found to be rather short ranged and limited to a single magnetic layer. Here we report a long-range antisymmetric interlayer exchange interaction in perpendicularly magnetized synthetic antiferromagnets with parallel and antiparallel magnetization alignments. Asymmetric hysteresis loops under an in-plane field reveal a unidirectional and chiral nature of this interaction, which results in canted magnetic structures. We explain our results by considering spin–orbit coupling combined with reduced symmetry in multilayers. Our discovery of a long-range chiral interaction provides an additional handle to engineer magnetic structures and could enable three-dimensional topological structures. An antisymmetric and chiral long range interlayer magnetic exchange interaction is measured, with implications for spintronics and chiral magnetic devices.

Korea Multi-Purpose Accelerator Complex (KOMAC) has been supporting a user beam service using 20- and 100-MeV proton beam facilities since the second half of 2013, and recently, beam facilities for radioisotope production and a low-flux proton beam have been built. A 100-MeV low-flux proton beam facility was constructed in 2007, which was due to the strong requirements of users in various R&D fields, such as space radiation, medical/biology, and radiation detectors. For the low-flux beam facility, the compact modules for beam flux control were designed, and various beam diagnosis tools were installed in the target room. In the process room, a user-friendly measurement system, consisting of DC power supplies, electrometers, NIM modules, was designed for data processing and acquisition. In addition, the ion beam facilities based on gas and metal ion sources provide an ion implantation service. In particular, beam analysis services, such as PIXE and RBS, have been started using the tandem accelerator. Moreover, analysis equipment for the material, device/electronic, and bio/medical fields was installed at KOMAC for confirming the effects of beam irradiation on various samples. Finally, we aim to provide users with a one-stop service from beam irradiation to measurement at KOMAC.

Many kinds of radioisotopes (RIs) produced by the high energy (100 ~ 200 MeV) proton accelerators are developed by the foreign R&D institutes and the worldwide demands are being increased continuously. The RI production using high energy proton beam higher than 50 MeV was not considerable because of the limit of the proton beam energy from existing proton accelerator facilities in Korea before 2013. The available maximum proton energy was 50 MeV from MC-50 cyclotron of Korea Institute of Radiological and Medical Sciences (KIRAMS) at that time. After the construction of a 100 MeV high-current and high-energy proton accelerator and a new irradiation facility for the RI production in 2013 and 2016 by the Korea Multi-purpose Accelerator Complex (KOMAC) at Korea Atomic Energy Research Institute (KAERI), we can make a plan for the new RI production of Cu-67, Sr-82 and so on. In the medical application fields, the worldwide demand of Sr-82 is being increased rapidly during last several years and the domestic demand of Cu-67 is also expected to be increased in near future. And alpha-emitters, such as Ac-225 and Ra-223, are becoming attractive to the users in the medical science fields in the future. The RI development plan of KOMAC was specified recently reflecting the recent environment changes and requirements from the users. In this paper, the results and present status of RI production and R&D facilities, calculation results related to the RI production yields, and future plans is presented.

Industrialization advances have led to an increase soil contamination by heavy metals. Among different technologies, in situ stabilization of metals combined with revegetation attracted attention. Therefore, this study aimed at comparing effects of biochars [rice husk biochar (RHB), maple leaves biochar (MLB)] and common inorganic amendments [red mud (RM), and steel slag (SS)] at different rates (0.5, 1, and 2% w/w) on leaching, and phytoavailability of metals (assessed using mustard green “Brassica juncea”). Soil pH in treated soils significantly (p< 0.01) increased, with the optimal pH ranges for plant growth observed in biochar-treated soils. The leaching of Cd, Cu, Pb, and Zn through soil significantly (p< 0.05) decreased in treated soils. Plant uptake and accumulation of Cd, Cu, Pb, and Zn decreased by 79–66, 13–19, 87–86, and 37–36% in RHB- and MLB-treated soils, respectively. Sequential extraction analysis pointed out that the major stabilization mechanism for metals using biochars involved the formation of organic and carbonate bonds, while for RM and SS was believed to involve the formation of inner sphere complexes with Fe/Al (hydr)oxides. The plant available fractions for Cd were generally higher than those for others. Overall, high dosage addition (2%) of each amendment offered the best compromise as it successfully reduced both leaching and phytoavailability of metals. Using MLB for the first time, showed promising results to immobilize metals with an increase in plant biomass.

In the realm of two-dimensional (2D) crystal growth, the chemical composition often determines the thermodynamically favored crystallographic structures. This relationship poses a challenge in synthesizing novel 2D crystals without altering their chemical elements, resulting in the rarity of achieving specific crystallographic symmetries or lattice parameters. We present 2D polymorphic FeAs crystals that completely differ from bulk orthorhombic FeAs (Pnma), differing in the stacking sequence, i.e., polytypes. Preparing polytypic FeAs outlines a strategy for independently controlling each symmetry operator, which includes the mirror plane for 2Q-FeAs (I4/mmm) and the glide plane for 1Q-FeAs (P4/nmm). As such, compared to bulk FeAs, polytypic 2D FeAs shows highly anisotropic properties such as electrical conductivity, Young’s modulus, and friction coefficient. This work represents a concept of expanding 2D crystal libraries with a given chemical composition but various crystal symmetries.

A proper control of defects in TiO2thin films is challenging work for enhancing the photoelectrochemical (PEC) efficiency in water splitting processes. Additionally, a deep understanding of how defects affect the PEC performance of TiO2thin films is of great interest for achieving better performance. With these aims, we prepared defective amorphous TiOxthin films at various growth temperatures by atomic layer deposition using tetrakis(dimethylamido)titanium as the Ti precursor. Careful X-ray photoelectron spectroscopy and electron spin resonance spectroscopy analyses revealed that the defect concentration in the TiOxthin films can be controlled by adjusting the growth temperature during the ALD process. We also evaluated the light absorption properties of the deposited TiOxthin films using ultraviolet–visible absorption spectroscopy. And it was found that the TiOxthin film deposited at a growth temperature of 200 °C exhibited the highest defect concentration and the highest photocurrent density of 0.051 mA/cm2at 1.23 V vs reversible hydrogen electrode (RHE) compared to those of the other films. The light absorption efficiency, photogenerated charge separation efficiency, and charge transfer efficiency of defective amorphous TiOxthin films were carefully studied to understand the correlation between the defect concentration in the prepared TiOxthin film and its PEC activity. This study provides insight into the PEC properties of defective amorphous ALD-TiOxthin films.

The lifetime of beryllium reflector assemblies is usually determined by neutron irradiation induced swelling, which results in mechanical interferences or fractures of the beryllium elements. Therefore, the dimensional stability and microstructure variations of beryllium during irradiation are important issues to study. In this paper, the microstructure characteristics of S-200-F and EHP-56 beryllium blocks, which were manufactured by using vacuum hot pressing (VHP) and hot extrusion (HE), respectively, were investigated. BeO distributions, grain shapes, and preferred orientations were investigated by using SEM-EPMA and SEM-EBSD systems. Dissimilarly to S-200-F, a strong fiber texture developed in the EHP-56 during the HE process; the basal planes in the majority of grains were arranged along the extrusion direction. To emulate the microstructure evolution during neutron irradiation, we irradiated the electro-polished surface of EHP-56 with protons at room temperature, where the acceleration voltage and the number of protons were 120 keV and 2.0 × 1018ions/cm2, respectively. Irradiation-induced cavities were observed to be considerably longer along the basal plane in the EHP-56 specimen. Correspondingly, the amount of dimensional change was smaller along the direction parallel to the basal plane.