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We previously demonstrated that C-X-C Motif Chemokine Ligand 12 (CXCL12) is primarily secreted by dermal fibroblasts in response to androgens and induces hair miniaturization in the mouse androgenic alopecia (AGA) model. However, the direct effects of androgen-induced CXCL12 on dermal papilla cells (DPCs) and dermal sheath cup cells (DSCs) have not been demonstrated. First, we compared single-cell RNA sequencing data between mouse and human skin, and the results show that CXCL12 is highly co-expressed with the androgen receptor (AR) in the DPCs and DSCs of only human hair. Immunohistochemistry also showed that CXCL12 is co-expressed with the AR in the DPCs and DSCs of human hair follicles. In human hair organ culture, androgens also increased CXCL12 expression in DPCs and DSCs and reduced hair length, while the CXCL12 antibody increased hair length via AR inactivation. CXCL12 mRNA was upregulated by androgen treatment in primary human DPCs and DSCs. On the contrary, AR inhibitors or siRNA treatment reduced CXCL12 expression. Collectively, these results suggest that CXCL12 is co-expressed with the AR in the DPCs and DSCs of human hair follicles; therefore, inhibition of CXCL12 using antibodies is a promising strategy for AGA treatment. [ABSTRACT FROM AUTHOR]

Developing thin-film sheets made of oxide-based solid electrolytes is essential for fabricating surface-mounted ultracompact multilayer oxide solid-state batteries. To this end, solid-electrolyte slurry must be optimized for excellent dispersibility. Although oxide-based solid electrolytes for multilayer structures require sintering, high processing temperatures cause problems such as Li-ion volatilization and reactions with graphite anodes. Thus, low-temperature sinterable oxide-based solid-electrolyte materials should be devised. We successfully developed the conditions for producing thin films from 21 μm thick solid-electrolyte sheets of Li2O-B2O3-Al2O3, one of the most promising candidates for multilayer solid-state batteries. A comprehensive analysis of the fabricated thin films included X-ray diffraction (XRD) to confirm their amorphous structure, scanning electron microscopy (SEM) for particle morphology, and contact angle measurements to verify surface hydrophilicity. Evaluation of a 32-layer bulk sample of solid-electrolyte sheets revealed an ionic conductivity of 2.33 × 10−7 S/cm and charge transfer resistance of 100.1 kΩ at a sintering temperature of 430 °C. Based on these results, cathode and anode active materials will be applied to develop high-energy-density multilayer ceramic batteries with hundreds of layers in future work. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicle (UAV) imaging provides the ability to obtain high-resolution images at a lower cost than satellite imagery and aerial photography. However, multiple UAV images need to be mosaicked to obtain images of large areas, and the resulting UAV multispectral image mosaics typically contain seam lines. To address this problem, we applied irradiance, vignette, and bidirectional reflectance distribution function (BRDF) filters and performed field work using a DJI Mavic 3 Multispectral (M3M) camera to collect data. We installed a calibrated reference tarp (CRT) in the center of the collection area and conducted three types of flights (BRDF, vignette, and validation) to measure the irradiance, radiance, and reflectance—which are essential for irradiance correction—using a custom reflectance box (ROX). A vignette filter was generated from the vignette parameter, and the anisotropy factor (ANIF) was calculated by measuring the radiance at the nadir, following which the BRDF model parameters were calculated. The calibration approaches were divided into the following categories: a vignette-only process, which solely applied vignette and irradiance corrections, and the full process, which included irradiance, vignette, and BRDF. The accuracy was verified through a validation flight. The radiance uncertainty at the seam line ranged from 3.00 to 5.26% in the 80% lap mode when using nine images around the CRT, and from 4.06 to 6.93% in the 50% lap mode when using all images with the CRT. The term 'lap' in 'lap mode' refers to both overlap and sidelap. The images that were subjected to the vignette-only process had a radiance difference of 4.48–6.98%, while that of the full process images was 1.44–2.40%, indicating that the seam lines were difficult to find with the naked eye and that the process was successful. [ABSTRACT FROM AUTHOR]

Human activity recognition (HAR) technology is related to human safety and convenience, making it crucial for it to infer human activity accurately. Furthermore, it must consume low power at all times when detecting human activity and be inexpensive to operate. For this purpose, a low-power and lightweight design of the HAR system is essential. In this paper, we propose a low-power and lightweight HAR system using point-cloud data collected by radar. The proposed HAR system uses a pillar feature encoder that converts 3D point-cloud data into a 2D image and a classification network based on depth-wise separable convolution for lightweighting. The proposed classification network achieved an accuracy of 95.54%, with 25.77 M multiply–accumulate operations and 22.28 K network parameters implemented in a 32 bit floating-point format. This network achieved 94.79% accuracy with 4 bit quantization, which reduced memory usage to 12.5% compared to existing 32 bit format networks. In addition, we implemented a lightweight HAR system optimized for low-power design on a heterogeneous computing platform, a Zynq UltraScale+ ZCU104 device, through hardware–software implementation. It took 2.43 ms of execution time to perform one frame of HAR on the device and the system consumed 3.479 W of power when running. [ABSTRACT FROM AUTHOR]

Efficient spatial query processing in Graph Database Management Systems (GDBMSs) has become increasingly important owing to the prevalence of spatial graph data. However, current GDBMSs lack effective spatial indexing, causing performance issues with complex spatial graph queries. This study proposes a spatial index called Subgraph Integrated R-Tree (SGIR-Tree) for efficient spatial query processing in GDBMSs. The SGIR-Tree integrates the hierarchical R-Tree structure with the graph structure of GDBMSs by converting R-Tree elements into graph components like nodes and edges. The Minimum Bounding Rectangle (MBR) information of spatial objects and R-Tree nodes is stored as properties of these graph elements, and the leaf nodes are directly connected to the spatial nodes. This approach combines the efficiency of spatial indexing with the flexibility of graph databases, thereby allowing spatial query results to be directly utilized in graph traversal. Experiments using OpenStreetMap datasets demonstrate that the SGIR-Tree outperforms the previous approaches in terms of query overhead and index overhead. The results are expected to improve spatial graph data processing in various fields, including location-based service and urban planning, significantly advancing spatial data management in GDBMSs. [ABSTRACT FROM AUTHOR]

Bioluminescence, the light produced by biochemical reactions involving luciferases in living organisms, has been extensively investigated for various applications. It has attracted particular interest as an internal light source for theranostic applications due to its safe and efficient characteristics that overcome the limited penetration of conventional external light sources. Recent advancements in protein engineering technologies and protein delivery platforms have expanded the application of bioluminescence to a wide range of theranostic areas, including bioimaging, biosensing, photodynamic therapy, and optogenetics. This comprehensive review presents the fundamental concepts of bioluminescence and explores its recent applications across diverse fields. Moreover, it discusses future research directions based on the current status of bioluminescent systems for further expansion of their potential. [ABSTRACT FROM AUTHOR]

In this study, the anatase–rutile phase fraction of TiO2, which would play a vital role in the solid-state synthesis of BaTiO3, was controlled to form a composite phase. The composite TiO2 was applied to a solid-state synthesis reaction, and the tetragonality, dielectric properties, and microstructure of the resulting BaTiO3 powders were analyzed under different synthesis conditions of TiO2. Furthermore, a comparative analysis of solid-state-synthesized BaTiO3 powders prepared using anatase, rutile, and mixed (anatase + rutile) TiO2 was performed to elucidate the mechanism of improvement in the sintering behavior and dielectric properties of the BaTiO3 powder synthesized using the composite TiO2. As a result of applying composite TiO2, BaTiO3 powder with excellent tetragonality was synthesized. In addition, it is effective in powder growth and the control of powder morphology, so sintering and dielectric properties can be improved at relatively low temperatures. [ABSTRACT FROM AUTHOR]

Prefabrication, one of the methods to increase productivity by moving construction activity to factory work, has evolved into multi-trade prefabrication. Although previous studies have introduced the merits and directions of multi-trade prefabrication technology, various design and installation techniques must be developed for the economical application of multi-trade prefabrication. This study aims to provide an economical design for prefabricated mechanical, electrical, and plumbing (MEP) rack (PMR) structural framing. We proposed five types of PMR structural framing techniques and analyzed their required channel material and labor inputs through a pilot test. The efficiency of PMR structural frames was examined by adjusting the supporting interval, moving the duct outside, and removing the upper framing. Economics and productivity analysis revealed that removing the upper framing method was the most effective when the coordination period was secured. Adjusting the supporting intervals is also an economical design option. The findings of this study can help enhance the economic feasibility of prefabrication and modularization of construction and their widespread utilization. [ABSTRACT FROM AUTHOR]

The mechanical properties of Ti-6Al-4V alloy are affected by its microstructures. However, the effects of these microstructures on the high cycle fatigue behavior of Ti-6Al-4V alloy with a mixed structure (α + β phases) remain unknown. In this study, three alloy specimens were prepared using different hot-deformation methods, and their microstructures were investigated by optical microscopy and scanning electron microscopy. Fatigue tests were then performed to determine their high cycle fatigue and fatigue crack propagation behavior. All specimens showed a bimodal structure, but the morphology of each phase (e.g., diameter, shape, and volume fraction) showed notable differences. Among the samples prepared, the forged sample (FS) showed the lowest fatigue strength in all cycles. The fatigue strength of the homogeneously rolled sample (HS) was slightly higher than that of the rolled sample (RS) below 106 cycles but lower above 106 cycles. Compared with those of RS and HS, the secondary α (αs) grain width of FS was twofold larger. The interconnected primary α (αp) phase clusters in HS appeared to promote microcrack propagation. [ABSTRACT FROM AUTHOR]

Seoul virus (SEOV), an etiological agent for hemorrhagic fever with renal syndrome, poses a significant public health threat worldwide. This study evaluated the feasibility of a mobile Biomeme platform for facilitating rapid decision making of SEOV infection. A total of 27 Rattus norvegicus were collected from Seoul Metropolitan City and Gangwon Province in Republic of Korea (ROK), during 2016–2020. The serological and molecular prevalence of SEOV was 5/27 (18.5%) and 2/27 (7.4%), respectively. SEOV RNA was detected in multiple tissues of rodents using the Biomeme device, with differences in Ct values ranging from 0.6 to 2.1 cycles compared to a laboratory benchtop system. Using amplicon-based next-generation sequencing, whole-genome sequences of SEOV were acquired from lung tissues of Rn18-1 and Rn19-5 collected in Gangwon Province. Phylogenetic analysis showed a phylogeographical diversity of rat-borne orthohantavirus collected in Gangwon Province. We report a novel isolate of SEOV Rn19-5 from Gangwon Province. Our findings demonstrated that the Biomeme system can be applied for the molecular diagnosis of SEOV comparably to the laboratory-based platform. Whole-genome sequencing of SEOV revealed the phylogeographical diversity of orthohantavirus in the ROK. This study provides important insights into the field-deployable diagnostic assays and genetic diversity of orthohantaviruses for the rapid response to hantaviral outbreaks in the ROK. [ABSTRACT FROM AUTHOR]

When the uniformity of the magnetization yoke is low, a mismatch occurs between the physical rotation center and the center due to the magnetic force after magnetization. This discrepancy in rotation can cause issues such as vibration and noise during high-speed rotation, which in the long term leads to a decrease in the lifespan of the motor. In addition, in order to minimize the problem of motor lifespan when a vehicle is used for more than 10 years after purchase, the problems caused by magnetization should be solved as far as possible. In this study, magnetization yokes were designed in various ways to optimize the factors that affect the magnetic properties after the magnetization of the Nd2Fe14B permanent magnets used in electric motors. In the case of a 50 µm deviation between the coils wound inside the magnetization yoke, the magnetic property imbalance of the Nd2Fe14B magnets and the motor characteristics are not significantly affected after magnetization. However, when the center of the coil wound inside the yoke is shifted from the center of the yoke, the magnetic field is generated unevenly, which degrades both the magnetic and motor characteristics of the Nd2Fe14B magnet. Therefore, it is very important to control the center of the coil that generates the external magnetic field in the magnetized yoke in order to magnetize the Nd2Fe14B magnet with excellent magnetic properties. [ABSTRACT FROM AUTHOR]

In this work, we present the overground prototype gait-rehabilitation robot for using motion assistance and training for paralyzed patients. In contrast to the existing gait-rehabilitation robots, which focus on the sagittal plane motion of the hip and knee, we aim to develop a mobile-based pelvic support gait-rehabilitation system that includes a pelvic obliquity support mechanism and a lower-limb exoskeleton. To achieve this, a scissor mechanism is proposed to generate the paralyzed patient's pelvic obliquity motion and weight support. Moreover, the lower limb exoskeleton robot is integrated with the developed system to provide the patient's gait by correcting mechanical aids. We used computer-aided analysis to verify the performance of the prototype hardware itself. Through these methods, it was shown that our motor can sufficiently lift 100 kg of user weight through the scissor mechanism, and that the mobile driving wheel motor can operate at a speed of 1.6 m/s of human walking, showing that it can be used for gait rehabilitation of patients in need of a lower speed. In addition, we verified that the system drives the model by generating pelvic motion, and we verified the position controller of the integrated system, which supports the multi-degree motion by creating hip/knee/pelvic motion with a human dummy mannequin and systems. We believe that the proposed system can help address the complex rehabilitation motion assistance and training of paralyzed patients. [ABSTRACT FROM AUTHOR]

The ability to accurately predict the early progression of hemorrhagic fever with renal syndrome (HFRS) is crucial for reducing morbidity and mortality rates in severely affected patients. However, the utility of biomarkers for predicting clinical outcomes remains elusive in HFRS. The aims of the current study were to analyze the serum levels of immune function-related proteins and identify novel biomarkers that may help ascertain clinical outcomes of HFRS. Enzyme-linked immunosorbent assay, Luminex, and bioanalyzer assays were used to quantitatively detect 15 biomarkers in 49 serum samples of 26 patients with HFRS. High hemoglobin (HGB) and low urine output (UO) levels were identified as potential biomarkers associated with the acute HFRS. The serum soluble urokinase plasminogen activator receptor (suPAR) and C-X-C motif chemokine ligand 10 (CXCL10) values increased in the early phase of diseases. Elevated suPAR, interleukin-10 (IL-10), CXCL10, and decreased transforming growth factor-beta 3 (TGF-β3) were representative predictors of the disease severity. Upregulation of the HGB showed a significant correlation with high levels of suPAR and CXCL10. Reduced UO positively correlated with increased suPAR, CXCL10, and TGF-β2, and decreased vascular endothelial growth factor and TGF-β3. The changing HGB and UO criteria, high suPAR, IL-10, CXCL10, and low TGF-β3 of HFRS raise significant awareness for physicians regarding prospective biomarkers for monitoring early warning signs of HFRS. This study provides critical insights into the clinical and immunological biomarkers for disease severity and progression in patients with HFRS to identify early predictions of fatal outcomes. [ABSTRACT FROM AUTHOR]

A metal matrix composite was developed through a unique liquid pressing infiltration process to study the wear mechanism of a TiC reinforced AISI 1020 steel matrix. The microstructure, hardness, and wear behaviors of the TiC/AISI 1020 composite were compared with commercial AISI 52100 bearing steel. Microstructural analysis showed that there were no defects, such as pores or agglomeration of reinforcement particles, and about 60% of the volume of TiC was uniformly dispersed. In the case of the AISI 52100 alloy, the hardness was 62.42 HRC, which was similar to the 62.84 HRC value of the as-cast TiC/AISI 1020 composite. After the quenching heat treatment, the Rockwell hardness of the composite increased to 76.64 HRC, which was attributed to the martensitic transformation of the AISI 1020 matrix. As a result of the pin-on-disc wear test with high contact pressure, the wear width of AISI 52100 was 2937 μm, which was approximately 4.3 times wider than that of the heat-treated metal matrix composite (682 μm). The wear depths of AISI 52100 and the heat-treated composite were 2.6 μm and 0.5 μm, respectively, indicating that TiC/AISI 1020 exhibited excellent wear resistance compared with bearing steel. Improved wear resistance of the TiC/AISI 1020 composite originates from uniformly distributed TiC, with an increase in the hardness due to the heat treatment. [ABSTRACT FROM AUTHOR]

In this study, different volume fractions of silicon-carbide-reinforced AA2024 matrix composites were successfully fabricated using stir-casting (SC) and die-casting (DC) processes. The microstructural difference and physical properties of the composites during the manufacturing process were investigated in detail. The microstructural analysis found that the composite produced by the SC process had some reinforcement clusters and pores; however, defects and clusters significantly decreased after the DC process. In particular, the degree of reinforcement dispersion was quantitatively analyzed and compared before and after the DC process using the dispersion-analysis method. As a result of quantitative evaluation, the degree of dispersion was improved 2.5, 4.6, and 4.0 times with 3 vol.%, 6 vol.%, and 9 vol.% SiC-reinforced composite after the DC process, respectively. The electron backscatter diffraction (EBSD) analysis showed that the grain size of the 9 vol.% SiC-reinforced DC composite (17.67 μm) was 75% smaller than that of the SC composite (68.06 μm). The average tensile strength and hardness of the 9 vol.% SiC-reinforced DC composite were 2 times higher than those of the AA2024 matrix. The superior mechanical properties of the DC-processed composite can be attributed to the increase in dispersivity of the SiC particles and to decreases in defects and grain size during the DC process. [ABSTRACT FROM AUTHOR]

For developing subminiature and highly integrated multilayer inductors, soft magnetic powder was used; however, its ferrite magnetic component is characterized by high resistivity and reduced direct current saturation, leading to the deterioration of the inductor under high currents. Therefore, herein, to improve the electromagnetic properties of thin-film inductors, Fe nanopowder was used to increase the volume fraction of magnetic sheets. Surface treatment was performed by using silane coupling agents, which improved the bonding strength and dispersibility of the Fe nanopowder with a heterogeneous epoxy binder. For uniform surface treatment on the nanopowder, the silane-treated powder was aged for 24 h, at a temperature of 3 °C. The surface-treated Fe nanopowder was used with a mixing ratio of the soft magnetic powder (coarse:fine:nano) of 7:2.5:0.5 wt.%; this was successful in producing a flexible and highly densified magnetic sheet. As a result, the volume fraction of the magnetic sheet for thin-film inductors to which a low-temperature aging-treated nanopowder was applied was significantly improved. [ABSTRACT FROM AUTHOR]

The antiviral effect of a catalytic RNA-hydrolyzing antibody, 3D8 scFv, for intranasal administration against avian influenza virus (H1N1) was described. The recombinant 3D8 scFv protein prevented BALB/c mice against H1N1 influenza virus infection by degradation of the viral RNA genome through its intrinsic RNA-hydrolyzing activity. Intranasal administration of 3D8 scFv (50 μg/day) for five days prior to infection demonstrated an antiviral activity (70% survival) against H1N1 infection. The antiviral ability of 3D8 scFv to penetrate into epithelial cells from bronchial cavity via the respiratory mucosal layer was confirmed by immunohistochemistry, qRT-PCR, and histopathological examination. The antiviral activity of 3D8 scFv against H1N1 virus infection was not due to host immune cytokines or chemokines, but rather to direct antiviral RNA-hydrolyzing activity of 3D8 scFv against the viral RNA genome. Taken together, our results suggest that the RNase activity of 3D8 scFv, coupled with its ability to penetrate epithelial cells through the respiratory mucosal layer, directly prevents H1N1 virus infection in a mouse model system. [ABSTRACT FROM AUTHOR]

Hepatitis A virus (HAV) is a serious threat to public health worldwide. We used multiplex polymerase chain reaction (PCR)-based next-generation sequencing (NGS) to derive information on viral genetic diversity and conduct precise phylogenetic analysis. Four HAV genome sequences were obtained using multiplex PCR-based NGS. HAV whole-genome sequence of one sample was obtained by conventional Sanger sequencing. The HAV strains demonstrated a geographic cluster with sub-genotype IA strains in the Republic of Korea. The phylogenetic pattern of HAV viral protein (VP) 3 region showed no phylogenetic conflict between the whole-genome and partial-genome sequences. The VP3 region in serum and stool samples showed sensitive detection of HAV with differences of quantification that did not exceed <10 copies/μL than the consensus VP4 region using quantitative PCR (qPCR). In conclusion, multiplex PCR-based NGS was implemented to define HAV genotypes using nearly whole-genome sequences obtained directly from hepatitis A patients. The VP3 region might be a potential candidate for tracking the genotypic origin of emerging HAV outbreaks. VP3-specific qPCR was developed for the molecular diagnosis of HAV infection. This study may be useful to predict for the disease management and subsequent development of hepatitis A infection at high risk of severe illness. [ABSTRACT FROM AUTHOR]

The development of anticancer drugs remains challenging owing to the potential for drug resistance. The simultaneous inhibition of multiple targets involved in cancer could overcome resistance, and these agents would exhibit higher potency than single-target inhibitors. Protein kinases represent a promising target for the development of anticancer agents. As most multi-kinase inhibitors are heterocycles occupying only the hinge and hydrophobic region in the ATP binding site, we aimed to design multi-kinase inhibitors that would occupy the ribose pocket, along with the hinge and hydrophobic region, based on ATP-kinase interactions. Herein, we report the discovery of a novel 4′-thionucleoside template as a multi-kinase inhibitor with potent anticancer activity. The in vitro evaluation revealed a lead 1g (7-acetylene-7-deaza-4′-thioadenosine) with potent anticancer activity, and marked inhibition of TRKA, CK1δ, and DYRK1A/1B kinases in the kinome scan assay. We believe that these findings will pave the way for developing anticancer drugs. [ABSTRACT FROM AUTHOR]

The wear behavior of AISI304 stainless steel was investigated under dry, water-, and oil-lubricated conditions. A block-on-disk wear test was conducted in this work, since the test conditions could be controlled easily. For oil-lubricated contact, a significant amount of thin and elongated cutting chip-like debris was observed. This is attributed to the high lubricating effect of oil. Strain-induced martensitic (SIM) transformation was observed for all AISI304 blocks after the wear test, while AISI304 consisted of a single γ-austenite phase prior to the wear test. The Stribeck curve and the corresponding lubrication regimes were also considered to explain the wear behaviors and lubrication effect of AISI304. In comparison to the dry or water-lubricated conditions, which fall in the boundary lubrication regime at a low rotation speed, it is considered that the high viscosity of the oil-based lubricant causes the lubrication condition to enter the mixed lubrication regime early at a lower speed, thus reducing the specific wear rate over the 100–300 rpm range. [ABSTRACT FROM AUTHOR]

Paramyxoviruses, negative-sense single-stranded RNA viruses, pose a critical threat to human public health. Currently, 78 species, 17 genera, and 4 subfamilies of paramyxoviruses are harbored by multiple natural reservoirs, including rodents, bats, birds, reptiles, and fish. Henipaviruses are critical zoonotic pathogens that cause severe acute respiratory distress and neurological diseases in humans. Using reverse transcription-polymerase chain reaction, 115 Crocidura species individuals were examined for the prevalence of paramyxovirus infections. Paramyxovirus RNA was observed in 26 (22.6%) shrews collected at five trapping sites, Republic of Korea. Herein, we report two genetically distinct novel paramyxoviruses (genus: Henipavirus): Gamak virus (GAKV) and Daeryong virus (DARV) isolated from C. lasiura and C. shantungensis, respectively. Two GAKVs and one DARV were nearly completely sequenced using next-generation sequencing. GAKV and DARV contain six genes (3′-N-P-M-F-G-L-5′) with genome sizes of 18,460 nucleotides and 19,471 nucleotides, respectively. The phylogenetic inference demonstrated that GAKV and DARV form independent genetic lineages of Henipavirus in Crocidura species. GAKV-infected human lung epithelial cells elicited the induction of type I/III interferons, interferon-stimulated genes, and proinflammatory cytokines. In conclusion, this study contributes further understandings of the molecular prevalence, genetic characteristics and diversity, and zoonotic potential of novel paramyxoviruses in shrews. [ABSTRACT FROM AUTHOR]

In this study, to evaluate the effect of boron carbide (B4C) addition on the wear performance of aluminum (Al), Al6061 and 5, 10, and 20 vol.% B4C/Al6061 composites were manufactured using the stir casting and hot rolling processes. B4C particles were randomly dispersed during the stir casting process; then, B4C particles were arranged in the rolling direction using a hot rolling process to further improve the B4C dispersion and wear resistance of the composites. Furthermore, a continuous interfacial layer between B4C and the Al6061 matrix was generated by diffusion of titanium (Ti) and chromium (Cr) atoms contained in the Al6061 alloy. Wear depth and width of the composites decreased with increasing B4C content. Furthermore, with B4C addition, coefficient of friction (COF) improved as compared with that of Al6061. The results indicate that interface-controlled, well-aligned B4C particles in the friction direction can effectively increase the wear properties of Al alloys and improve their hardness. [ABSTRACT FROM AUTHOR]

Whole-genome sequencing of infectious agents enables the identification and characterization of emerging viruses. The MinION device is a portable sequencer that allows real-time sequencing in fields or hospitals. Hantaan orthohantavirus (Hantaan virus, HTNV), harbored by Apodemus agrarius, causes hemorrhagic fever with renal syndrome (HFRS) and poses a critical public health threat worldwide. In this study, we aimed to evaluate the feasibility of using nanopore sequencing for whole-genome sequencing of HTNV from samples having different viral copy numbers. Amplicon-based next-generation sequencing was performed in A. agrarius lung tissues collected from the Republic of Korea. Genomic sequences of HTNV were analyzed based on the viral RNA copy numbers. Amplicon-based nanopore sequencing provided nearly full-length genomic sequences of HTNV and showed sufficient read depth for phylogenetic analysis after 8 h of sequencing. The average identity of the HTNV genome sequences for the nanopore sequencer compared to those of generated from Illumina MiSeq revealed 99.8% (L and M segments) and 99.7% (S segment) identities, respectively. This study highlights the potential of the portable nanopore sequencer for rapid generation of accurate genomic sequences of HTNV for quicker decision making in point-of-care testing of HFRS patients during a hantavirus outbreak. [ABSTRACT FROM AUTHOR]

The number of elderly people has increased as life expectancy increases. As muscle strength decreases with aging, it is easy to feel tired while walking, which is an activity of daily living (ADL), or suffer a fall accident. To compensate the walking problems, the terrain environment must be considered, and in this study, we developed the locomotion mode recognition (LMR) algorithm based on the gaussian mixture model (GMM) using inertial measurement unit (IMU) sensors to classify the five terrains (level walking, stair ascent/descent, ramp ascent/descent). In order to meet the walking conditions of the elderly people, the walking speed index from 20 to 89 years old was used, and the beats per minute (BPM) method was adopted considering the speed range for each age groups. The experiment was conducted with the assumption that the healthy people walked according to the BPM rhythm, and to apply the algorithm to the exoskeleton robot later, a full/individual dependent model was used by selecting a data collection method. Regarding the full dependent model as the representative model, the accuracy of classifying the stair terrains and level walking/ramp terrains is BPM 90: 98.74%, 95.78%, BPM 110: 99.33%, 95.75%, and BPM 130: 98.39%, 87.54%, respectively. The consumption times were 14.5, 21.1, and 14 ms according to BPM 90/110/130, respectively. LMR algorithm that satisfies the high classification accuracy according to walking speed has been developed. In the future, the LMR algorithm will be applied to the actual hip exoskeleton robot, and the gait phase estimation algorithm that estimates the user's gait intention is to be combined. Additionally, when a user wearing a hip exoskeleton robot walks, we will check whether the combined algorithm properly supports the muscle strength. [ABSTRACT FROM AUTHOR]

The virus behind the current pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the etiology of novel coronavirus disease (COVID-19) and poses a critical public health threat worldwide. Effective therapeutics and vaccines against multiple coronaviruses remain unavailable. Single-chain variable fragment (scFv), a recombinant antibody, exhibits broad-spectrum antiviral activity against DNA and RNA viruses owing to its nucleic acid-hydrolyzing property. The antiviral activity of 3D8 scFv against SARS-CoV-2 and other coronaviruses was evaluated in Vero E6 cell cultures. Viral growth was quantified with quantitative RT-qPCR and plaque assay. The nucleic acid-hydrolyzing activity of 3D8 was assessed through abzyme assays of in vitro viral transcripts and cell viability was determined by MTT assay. We found that 3D8 inhibited the replication of SARS-CoV-2, human coronavirus OC43 (HCoV-OC43), and porcine epidemic diarrhea virus (PEDV). Our results revealed the prophylactic and therapeutic effects of 3D8 scFv against SARS-CoV-2 in Vero E6 cells. Immunoblot and plaque assays showed the reduction of coronavirus nucleoproteins and infectious particles, respectively, in 3D8 scFv-treated cells. These data demonstrate the broad-spectrum antiviral activity of 3D8 against SARS-CoV-2 and other coronaviruses. Thus, it could be considered a potential antiviral countermeasure against SARS-CoV-2 and zoonotic coronaviruses. [ABSTRACT FROM AUTHOR]

An epidemiological investigation was conducted for a scrub typhus case reported in a U.S. Forces Korea military patient in the Republic of Korea in November 2018. The patient had a fever, maculopapular rash, and an eschar. The full-length sequence of Orientia tsutsugamushi 56-kDa type-specific antigen (TSA) gene was obtained from eschar tissue by multiplex PCR-based Next Generation Sequencing for genetic identification. Based on the 56-kDa TSA gene, the O. tsutsugamushi aligned most closely with the Boryong strain. [ABSTRACT FROM AUTHOR]

In this study, to fabricate neutron shielding material, boron carbide (B4C)-reinforced aluminum (Al) alloy composites were successfully fabricated by stir casting followed by a hot rolling process. Microstructural analysis of B4C/Al6061 composites with different volume fractions (5, 10, 20, 25, and 30%) revealed that the composites had volume ratios similar to the target volume ratios of B4C. Furthermore, B4C reinforcements were uniformly dispersed in the Al matrix, forming multi-interfacial layers of Al4C3/(Ti,Cr)B2. The interfacial layer generated during stir casting maintained its own structure after the hot rolling process, indicating strong interfacial bonding strength. The tensile strengths of the B4C/Al6061 composites increased to 20 vol.% and stayed above the value for Al6061, even reaching 30 vol.%. The measured thermal neutron shielding rate increased with increasing B4C content, and the highest thermal neutron shielding rate was observed at 30 vol.% composite, which corresponds to 95.6% neutron shielding at 0.158-cm thickness. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce, examine, and evaluate the industrial experiences and effectiveness of a Thyristor Controlled Series Compensator (TCSC) replica controller installed in Korea in 2019 through a review of its configuration, test platform, and practical application, and further to propose operational guidelines for replica controllers. Four representative practical cases were conducted: a Dynamic Performance Test (DPT) under a sufficiently large-scale power system prior to the Site Acceptance Test (SAT), pre-verification for on-site controller modification during operation stage, parameter tuning to mitigate the control interaction, and time domain simulation for Sub-Synchronous Torsional Interaction (SSTI). None of these four cases can be performed in a Factory Acceptance Test (FAT) or on-site. Therefore, TCSC control performance was accurately verified under the entire Korean power system based on a large-scale real-time simulator, which demonstrated its effectiveness as a powerful tool for operations including multiple power electronics devices. Our review herein of these four practical cases is expected to show the usefulness of replica controllers, to demonstrate their strength to deal with practical field events, and to contribute to the further expansion of the application area from a perspective of electric utility. [ABSTRACT FROM AUTHOR]

This study was conducted on titanium diboride (TiB2) reinforced Al metal matrix composites (MMCs) with improved properties using a TiB2 and aluminum (Al) 1050 alloy. Al composites reinforced with fine TiB2 at volume ratios of more than 60% were successfully fabricated via the liquid pressing infiltration (LPI) process, which can be used to apply gas pressure at a high temperature. The microstructure of the TiB2–Al composite fabricated at 1000 °C with pressurization of 10 bar for 1 h showed that molten Al effectively infiltrated into the high volume-fraction TiB2 preform due to the improved wettability and external gas pressurization. In addition, the interface of TiB2 and Al not only had no cracks or pores but also had no brittle intermetallic compounds. In conclusion, TiB2–Al composite, which has a sound microstructure without defects, has improved mechanical properties, such as hardness and strength, due to effective load transfer from the Al matrix to the fine TiB2 reinforcement. [ABSTRACT FROM AUTHOR]

Adiponectin is an adipocyte-derived cytokine having an insulin-sensitizing activity. During the phenotypic screening of secondary metabolites derived from the marine fungus Aspergillus terreus, a poly cyclin-dependent kinase (CDK) inhibitor butyrolactone I affecting CDK1 and CDK5 was discovered as a potent adiponectin production-enhancing compound in the adipogenesis model of human bone marrow-derived mesenchymal stem cells (hBM-MSCs). CDK5 inhibitors exhibit insulin-sensitizing activities by suppressing the phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ). However, the adiponectin production-enhancing activities of butyrolactone I have not been correlated with the potency of CDK5 inhibitor activities. In a target identification study, butyrolactone I was found to directly bind to PPARγ. In the crystal structure of the human PPARγ, the ligand-binding domain (LBD) in complex with butyrolactone I interacted with the amino acid residues located in the hydrophobic binding pockets of the PPARγ LBD, which is a typical binding mode of the PPARγ partial agonists. Therefore, the adiponectin production-enhancing effect of butyrolactone I was mediated by its polypharmacological dual modulator activities as both a CDK5 inhibitor and a PPARγ partial agonist. [ABSTRACT FROM AUTHOR]

Aluminum alloy (Al7075) composites reinforced with a high volume fraction of silicon carbide (SiC) were produced by a liquid-pressing process. The characterization of their microstructure showed that SiC particles corresponding to a volume fraction greater than 60% were uniformly distributed in the composite, and Mg2Si precipitates were present at the interface between the matrix and the reinforcement. A superior compressive strength (1130 MPa) was obtained by an effective load transfer to the hard ceramic particles. After solution heat treatment and artificial aging, the Mg2Si precipitates decomposed from rod-shaped large particles to smaller spherical particles, which led to an increase of the compressive strength by more than 200 MPa. The strengthening mechanism is discussed on the basis of the observed microstructural evolution. [ABSTRACT FROM AUTHOR]

Dry contact electrode-based EEG acquisition is one of the easiest ways to obtain neural information from the human brain, providing many advantages such as rapid installation, and enhanced wearability. However, high contact impedance due to insufficient electrical coupling at the electrode-scalp interface still remains a critical issue. In this paper, a two-wired active dry electrode system is proposed by combining finger-shaped spring-loaded probes and active buffer circuits. The shrinkable probes and bootstrap topology-based buffer circuitry provide reliable electrical coupling with an uneven and hairy scalp and effective input impedance conversion along with low input capacitance. Through analysis of the equivalent circuit model, the proposed electrode was carefully designed by employing off-the-shelf discrete components and a low-noise zero-drift amplifier. Several electrical evaluations such as noise spectral density measurements and input capacitance estimation were performed together with simple experiments for alpha rhythm detection. The experimental results showed that the proposed electrode is capable of clear detection for the alpha rhythm activation, with excellent electrical characteristics such as low-noise of 1.131 μVRMS and 32.3% reduction of input capacitance. [ABSTRACT FROM AUTHOR]

In this study, high volume fraction B4C reinforced Al matrix composites were fabricated with a liquid pressing process. Microstructural analysis by scanning electron microscope and a transmission electron microscopy shows a uniform distribution of the B4C reinforcement in the matrix, without any defects such as pore and unwanted reaction products. The compressive strength and wear properties of the Al7075 matrix and the composite were compared at room temperature, 100, 200, and 300 °C, respectively. The B4C reinforced composite showed a very high ultimate compression strength (UCS) over 1.4 GPa at room temperature. The UCS gradually decreased as the temperature was increased, and the UCS of the composite at 300 °C was about one third of the UCS of the composite at room temperature. The fractography of the compressive test specimen revealed that the fracture mechanism of the composites was the brittle fracture mode at room temperature during the compression test. However, at the elevated temperature, AMCs had a mixed mode of a brittle and ductile fracture mechanism under the compressive load. The composite produced by a liquid pressing process also showed superior wear resistance compared with the Al matrix. The result of the wear test indicates that the wear loss of the Al matrix at 300 °C was two times higher than that of the AMCs, which is attributed to the formation of a mechanically mixed layer (MML) in the composites at the high temperature. [ABSTRACT FROM AUTHOR]

Aluminium–copper composite materials were successfully fabricated using spark plasma sintering with Al and Cu powders as the raw materials. Al–Cu composite powders were fabricated through a ball milling process, and the effect of the Cu content was investigated. Composite materials composed of Al–20Cu, Al–50Cu, and Al–80Cu (vol.%) were sintered by a spark plasma sintering process, which was carried out at 520 °C and 50 MPa for 5 min. The phase analysis of the composite materials by X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) indicated that intermetallic compounds (IC) such as CuAl2 and Cu9Al4 were formed through reactions between Cu and Al during the spark plasma sintering process. The mechanical properties of the composites were analysed using a Vickers hardness tester. The Al–50Cu composite had a hardness of approximately 151 HV, which is higher than that of the other composites. The thermal conductivity of the composite materials was measured by laser flash analysis, and the highest value was obtained for the Al–80Cu composite material. This suggests that the Cu content affects physical properties of the Al–Cu composite material as well as the amount of intermetallic compounds formed in the composite material. [ABSTRACT FROM AUTHOR]

Aluminum (Al)-stainless steel 316L (SUS316L) composites were successfully fabricated by the spark plasma sintering process (SPS) using pure Al and SUS316L powders as raw materials. The Al-SUS316L composite powder comprising Al with 50 vol.% of SUS316L was prepared by a ball milling process. Subsequently, it was sintered at 630 °C at a pressure of 200 MPa and held for 5 min in a semisolid state. The X-ray diffraction (XRD) patterns show that intermetallic compounds such as Al13Fe4 and AlFe3 were created in the Al-SUS316L composite because the Al and SUS316L particles reacted together during the SPS process. The presence of these intermetallic compounds was also confirmed by using XRD, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and EDS mapping. The mechanical hardness of the Al-SUS316L composites was analyzed by a Vickers hardness tester. Surprisingly, the Al-SU316L composite exhibited a Vickers hardness of about 620 HV. It can be concluded that the Al-SUS316L composites fabricated by the SPS process are lightweight and high-hardness materials that could be applied in the engineering industry such as in automobiles, aerospace, and shipbuilding. [ABSTRACT FROM AUTHOR]

In this study, we have attempted to manufacture functionally graded materials (FGMs) using aluminum alloys 3003 and 6063 via a hot extrusion process to realize multifunctionality through achieving high strength and low weight. The FGMs were fabricated using Al3003 powder and Al6063 bulk to improve the interfacial properties. Particle size analysis and X-ray fluorescence of the Al3003 powder were used to analyze the composition of general Al3003; microstructure analysis revealed improved hardness with almost no defects, such as cracks at the interface between the two materials. The experimentally determined tensile strength of the composite was observed to be higher than the theoretical value calculated using the rule of mixtures; the strengthening mechanisms considered for the calculations were grain size reduction and precipitation hardening. In particular, we attempted to predict the strengthening effect resulting from the fine grain size of the powder and grain size reduction due to the extrusion process using the Hall–Petch equation. The Kelly–Tyson equation was also used to calculate the theoretical strength in the presence of the strengthening phases. Based on these results, it was confirmed that FGMs can be successfully produced using the hot extrusion process. [ABSTRACT FROM AUTHOR]

In this research, we successfully fabricate high-hardness and lightweight Al-Ti composites. Al-Ti composites powders with three compositions (Al-20, 50, and 80 vol.% Ti) are mixed using ball milling and subsequently subjected to spark plasma sintering (SPS). The microstructures and phases of the Al-Ti composites are characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) spectroscopy, and field emission-electron probe microanalysis (FE-EPMA). These tests confirm the presence of several intermetallic compounds (ICs) (Al3Ti, Al5Ti2, Al11Ti5) in the composites, and we are able to confirm that these ICs are produced by the reaction of Al and Ti during the SPS process. Furthermore, thermogravimetric-differential thermal analysis (TG-DTA) is used to analyze the formation behavior of the ICs. In addition, the mechanical properties of the composites are measured using their Vickers hardness and it is observed that the Al-80 vol.% Ti composite exhibits the highest hardness. Consequently, it is assumed that SPS is suitable for fabricating Al-Ti composites which represent the next-generation materials to be used in various industrial fields as high-hardness and lightweight materials. [ABSTRACT FROM AUTHOR]

Efforts to reduce greenhouse gas emissions constitute a worldwide trend. According to this trend, there are many plans in place for the replacement of conventional electric power plants operating using fossil fuels with renewable energy sources (RESs). Owing to current needs to expand the RES penetration in accordance to a new National power system plan, the importance of RESs is increasing. The RES penetration imposes various impacts on the power system, including transient stability. Furthermore, the fact that they are distributed at multiple locations in the power system is also a factor which makes the transient impact analysis of RESs difficult. In this study, the transient impacts attributed to the penetration of RESs are analyzed and compared with the conventional Korean electric power system. To confirm the impact of the penetration of RESs on transient stability, the effect was analyzed based on a single machine equivalent (SIME) configuration. Simulations were conducted in accordance to the Korean power system by considering the anticipated RES penetration in 2030. The impact of RES on transient stability was provided by a change in CCT by increasing of the RES penetration. [ABSTRACT FROM AUTHOR]

Probiotics are well known for their beneficial effects for animals, including humans and livestock. Here, we tested the probiotic activity of Lactobacillus paracasei expressing 3D8 scFv, a nucleic acid-hydrolyzing mini-antibody, in mice intestine. A total of 18 fecal samples derived from three different conditions at two different time points were subjected to high-throughput 16S ribosomal RNA (rRNA) metagenomic analyses. Bioinformatic analyses identified an average of 290 operational taxonomic units. After administration of L. paracasei, populations of the probiotics L. paracasei, Lactobacillus reuteri, and Pediococcus acidilactici increased, whereas the population of harmful bacteria such as Helicobacter species decreased. Furthermore, continuous administration of L. paracasei resulted in L. paracasei emerging as the dominant probiotic after competition with other existing probiotics. Expression of 3D8 scFv protein specifically increased the population of P. acidilactici, which is another probiotic. In summary, our results showed that L. paracasei expressing 3D8 scFv protein enhanced probiotic activity in mice intestine with no observable side effects. Thus, the system developed in this study may be a good tool for the expression of recombinant protein using probiotics. [ABSTRACT FROM AUTHOR]