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Due to the extremely high energy density of Li metal, Li metal batteries are regarded as one of the most promising candidates for next-generation energy storage systems. However, interfacial issues, particularly the unstable solid electrolyte interphase (SEI) and lithium dendritic growth, hinder practical application. Herein, we induce an anion-rich interface near the Li metal by introducing positively charged self-assembled monolayers (SAMs) on ceramic-coated separators to simultaneously stabilize the SEI and homogenize the Li deposition. The anion-rich interface, originating from the electrostatic attraction of SAMs, promotes the preferential decomposition of salt anions over organic solvent molecules, leading to the formation of a stable anion-derived inorganic component, notably LiF. Furthermore, the positively charged SAMs immobilize anions, significantly mitigating dendritic Li by improving the Li + transference number (∼0.73) and thereby mitigating dendritic Li growth. Hence, we present SAMs on ceramic-coated separators as an innovative way to improve the long-term cycling performance of Li metal batteries.

This review comprehensively examines the various applications of microalgae, focusing on their significant potential in producing biodiesel and hydrogen, serving as sustainable food sources, and their efficacy in treating both municipal and food-related wastewater. While previous studies have mainly focused on specific applications of microalgae, such as biofuel production or wastewater treatment, this review covers these applications comprehensively. It examines the potential for microalgae to be applied in various industrial sectors such as energy, food security, and environmental management. By bridging these different application areas, this review differs from previous studies in providing an integrated and multifaceted view of the industrial applications of microalgae. Since it is essential to increase the productivity of the process to utilize microalgae for various industrial applications, research trends in different microalgae cultivation processes, including the culture system (e.g., open ponds, closed ponds) or environmental conditions (e.g., pH, temperature, light intensity) to improve the productivity of biomass and valuable substances was firstly analyzed. In addition, microalgae cultivation technologies that can maximize the biomass and valuable substances productivity while limiting the potential for contamination that can occur when utilizing these systems have been described to maximize CO 2 reduction. In conclusion, this review has provided a detailed analysis of current research findings and technological innovations, highlighting the important role of microalgae in addressing global challenges related to energy, food supply, and waste management. It has also provided valuable insights into future research directions and potential commercial applications in several bio-related industries, and illustrated how important continued exploration and development in this area is to realize the full potential of microalgae., Competing Interests: Declarations Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Conflicts of interest There are no conflicts of interest to declare. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

The formation of a stable solid electrolyte interphase (SEI) layer is crucial for enhancing the safety and lifespan of Li metal batteries. Fundamentally, a homogeneous Li + behavior by controlling the chemical reaction at the anode/electrolyte interface is the key to establishing a stable SEI layer. However, due to the highly reactive nature of Li metal anodes (LMAs), controlling the movement of Li + at the anode/electrolyte interface remains challenging. Here, an advanced approach is proposed for coating a sacrificial layer called fluorinated self-assembled monolayer (FSL) on a boehmite-coated polyethylene (BPE) separator to form a stable SEI layer. By leveraging the strong affinity between the fluorine functional group and Li + , the rapid formation of a LiF-rich SEI layer in the cell production and early cycling stage is facilitated. This initial stable SEI formation promotes the subsequent homogeneous Li + flux, thereby improving the LMA stability and yielding an enhanced battery lifespan. Further, the mechanism behind the stable SEI layer generation by controlling the Li + dynamics through the FSL-treated BPE separator is comprehensively verified. Overall, this research offers significant contributions to the energy storage field by addressing challenges associated with LMAs, thus highlighting the importance of interfacial control in achieving a stable SEI layer., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

The Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak is capable of operating at a wide range of toroidal magnetic fields up to 3.5 T at the major radius. The electron cyclotron emission (ECE) diagnostic on KSTAR is required to cover a broad frequency range for electron temperature profile measurements in both the low and high field sides. To meet these broadband requirements, the ECE system consists of W-band (78-110 GHz) and D-band (110-162 GHz) heterodyne radiometers. The two radiometers are connected to 28 and 48 detection channels, respectively. However, since the absolute ECE calibration based on the hot-cold calibration has been very challenging, an alternative method of calibration was performed using Thomson scattering measurements and varying toroidal magnetic fields. As the toroidal magnetic field is scanned from 1.6 to 3.2 T in steps of 0.2 T, most of the 76 ECE channels are calibrated relatively by the electron temperature values of Thomson scattering in a narrow region (0.2 < r/a <0.6). In this article, the methodological details of the ECE calibration are described. In addition, to demonstrate the robustness of the ECE calibration factors, the calibrated electron temperature profiles from ECE measurements are compared with the ion temperature profiles in terms of the plasma position as the plasma positon shifts outward., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Composite solid electrolytes (CSEs) are newly emerging components for all-solid-state Li-metal batteries owing to their excellent processability and compatibility with the electrodes. Moreover, the ionic conductivity of the CSEs is one order of magnitude higher than the solid polymer electrolytes (SPEs) by incorporation of inorganic fillers into SPEs. However, their advancement has come to a standstill owing to unclear Li-ion conduction mechanism and pathway. Herein, the dominating effect of the oxygen vacancy (O vac ) in the inorganic filler on the ionic conductivity of CSEs is demonstrated via Li-ion-conducting percolation network model. Based on density functional theory, indium tin oxide nanoparticles (ITO NPs) are selected as inorganic filler to determine the effect of O vac on the ionic conductivity of the CSEs. Owing to the fast Li-ion conduction through the O vac inducing percolation network on ITO NP-polymer interface, LiFePO 4 /CSE/Li cells using CSEs exhibit a remarkable capacity in long-term cycling (154 mAh g -1 at 0.5C after 700 cycles). Moreover, by modifying the O vac concentration of ITO NPs via UV-ozone oxygen-vacancy modification, the ionic conductivity dependence of the CSEs on the surface O vac from the inorganic filler is directly verified., (© 2023 Wiley-VCH GmbH.)

Organic semiconductors employed in single crystalline form have several advantages over polycrystalline films, such as higher charge carrier mobility and better environmental stability. Herein, we report the fabrication and characterization of a solution-processed microsized single-crystalline organic wire of n -type N , N '-dipentyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C 5 ). The crystal was applied as an active layer in polymer-gated organic field-effect transistors (OFETs) and organic complementary inverter circuits. The single crystaiiline nature of PTCDI-C 5 wires were characterized using two-dimensional grazing incidence wide-angle X-ray diffraction (2D-GIXD) and polarized optical microscopy. OFETs with the PTCDI-C 5 crystals exhibited high n -type performance and air stability under ambient conditions. To investigate the electrical properties of the single-crystalline PTCDI-C 5 wire more precisely, OFETs with only one PTCDI-C 5 microwire in the channel were fabricated, and clear n -type characteristics with satisfactory saturation behavior were observed. The device with only one crystal wire exhibited characteristics with significantly lower variation compared to the multicrystal devices, which shows that the density of crystal wires is a critical factor in precisely investigating device performance. The devices exhibited a reversible threshold voltage shift under vacuum and oxygen conditions, without changing the charge carrier mobility. Light-sensitive characteristics were also observed. Additionally, this solution-processed, highly crystalline organic semiconductor can be used in high-performance organic electronic circuits as well as in gas or light sensors.

Appropriate rehabilitation of stroke patients at a very early phase results in favorable outcomes. However, the optimal strategy for very early rehabilitation is at present unclear due to the limited knowledge on the effects of very early initiation of rehabilitation based on voluntary exercise (VE). Environmental enrichment (EE) is a therapeutic paradigm for laboratory animals that involves complex combinations of physical, cognitive, and social stimuli, as well as VE. Few studies delineated the effect of EE on apoptosis in very early stroke in an experimental model. Although a minimal benefit of early rehabilitation in stroke models has been claimed in previous studies, these were based on a forced exercise paradigm. The aim of this study is to determine whether very early exposure to EE can effectively regulate Fas/FasL-mediated apoptosis following hypoxic-ischemic (HI) brain injury and improve neurobehavioral function. C57Bl/6 mice were housed for 2 weeks in either cages with EE or standard cages (SC) 3 h or 72 h after HI brain injury. Very early exposure to EE was associated with greater improvement in motor function and cognitive ability, reduced volume of the infarcted area, decreased mitochondria-mediated apoptosis, and decreased oxidative stress. Very early exposure to EE significantly downregulated Fas/FasL-mediated apoptosis, decreased expression of Fas, Fas-associated death domain, cleaved caspase-8/caspase-8, cleaved caspase-3/caspase-3, as well as Bax and Bcl-2, in the cerebral cortex and the hippocampus. Delayed exposure to EE, on the other hand, failed to inhibit the extrinsic pathway of apoptosis. This study demonstrates that very early exposure to EE is a potentially useful therapeutic translation for stroke rehabilitation through effective inhibition of the extrinsic and intrinsic apoptotic pathways., Competing Interests: SP was employed by Neuracle Science Co. Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lee, Song, Hwang, Baek, Baek, Kim, Park, Choi, Pyo and Cho.)

Organoid cultures have been developed to model intestinal stem cell (ISC) function in self-renewal and differentiation. Upon differentiation, the first fate decision for ISC and early progenitors to make is between secretory (Paneth cell, goblet cell, enteroendocrine cell, or tuft cell) and absorptive (enterocyte and M cell) lineages. Using genetic and pharmacological approaches, in vivo studies in the past decade have revealed that Notch signaling functions as a binary switch for the secretory vs. absorptive lineage decision in adult intestine. Recent breakthroughs in organoid-based assays enable real-time observation of smaller-scale and higher-throughput experiments in vitro, which have begun contributing to new understandings of mechanistic principles underlying intestinal differentiation. In this chapter, we summarize the in vivo and in vitro tools for modulating Notch signaling and assess its impact on intestinal cell fate. We also provide example protocols of how to use intestinal organoids as functional assays to study Notch activity in intestinal lineage decisions., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The aim of this work was to study on MgO-modified KOH activated biochar (AC) catalysts, in the pyrolysis of sawdust for the direct production of bio-jet fuels using a tandem micro-pyrolyzer. AC catalysts with various MgO contents (5 to 20 wt%) were synthesized using an impregnation method. The mesopores generated (4 to 18 nm) in the carbon has a great potential in the conversion of oxygenated to jet fuel. The importance of basic nature in the catalysts is demonstrated with the maximum bio-jet fuel yield of 29 % at 10 % MgO. Further, the temperature of 600 °C and a catalyst/sawdust ratio of 10 are identified as the optimal conditions. The nanosize of MgO and the synergism of acid and base sites seemed to enhance deoxygenation, via decarboxylation and decarbonylation, and oligomerization, which are required for jet fuel formation in high amounts from sawdust pyrolysis., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Porous structures have been utilized in tactile sensors to improve sensitivity owing to their excellent deformability. Recently, tactile sensors using porous structures have been used in practical applications, such as bio-signal monitoring. However, highly sensitive responses are limited to the low-pressure range, and their sensitivity significantly decreases in a higher-pressure range. Several approaches for developing tactile sensors with high sensitivity overing a wide pressure range have been proposed; however, achieving high sensitivity and wide sensing range remains a crucial challenge. This report presents a carbon nanotube (CNT)-coated CNT-polydimethylsiloxane (PDMS) composite having dual-scale pores for tactile sensors with high sensitivity over a wide pressure range. The porous polymer frame formed with dense pores of dual sizes facilitates the closure of large and small pores at low and high pressures, respectively. This results in an apparent increase in the number of contact points between the CNT-CNT at the pores even under a wide pressure range. Furthermore, the piezoresistivity of the CNT-PDMS composite contributes to achieving a high sensitivity of the tactile sensor over a wide pressure range. Based on these mechanisms, various human movements over a broad pressure spectrum are monitored to investigate the practical usefulness of the sensor., (© 2022 Wiley-VCH GmbH.)

The vibration-reducing ability of construction materials is generally described by the damping ratio of the materials. Previously, many studies on the damping ratio of concrete have been done, such as the addition of rubber, polymer, fiber, and recycled aggregates in the concrete. However, the application of these materials in construction is limited due to their drawbacks. This paper investigated the effect of the replacement ratio and the size of the hollow glass microspheres (HGM), cenospheres (CS), and graphite flakes (GF) on the damping ratio of mortar. Furthermore, rubber particles (RP), aluminum powder (AP), and natural fiber (NF) were investigated to find if they have a combination effect with HGM. The half-power bandwidth method was conducted to obtain the damping ratio at 28 days of curing, and the compressive and flexural strength tests were also conducted to study the mechanical properties of mortar that contained HGM, CS, and GF. The results show that increases in the size of HGM and the replacement ratio of sand with HGM lead to an increase in the damping ratio. Moreover, RP and NF do not provide a combination effect with HGM on the damping ratio, whereas the application of AP results in a drastic compressive strength decrease even with an increase in damping ratio when incorporated with HGM. Besides, an increase in the replacement percentage of CS also leads to an improvement in the damping ratio, and a smaller size and higher replacement ratio of GFs can improve the damping ratio compared to other additives. As a result, CS and GF are more effective than HGM. 50% replacement ratio of CS slightly reduced the compressive strength by 6.4 MPa while improving the damping ratio by 15%, and 10% replacement ratio of samller GF can enhance the flexural strength by over 4.55% while increasing the damping ratio by 20.83%.

Multimode Tonpilz transducers operate at longitudinal and flexural vibration modes simultaneously. Consequently, they have wider bandwidths than conventional single-mode transducers. Generally, the performance of Tonpilz transducers is analyzed using the finite element method (FEM), whereas the equivalent circuit method (ECM) has proven to be a fast and efficient alternative to the FEM. However, the ECM for analyzing the acoustic characteristics of multimode Tonpilz transducers has not yet been developed. To address this issue, an equivalent circuit for the multimode Tonpilz transducer is developed herein. The proposed ECM encompasses the flexural characteristics of the Tonpilz head mass, which is impossible with conventional equivalent circuits. Furthermore, a prototype of the multimode Tonpilz transducer was fabricated to verify the validity of the developed ECM. Additionally, the accuracy and compliance of the ECM were confirmed by comparing the measured performance of the transducer with that from the equivalent circuit analysis.

Environmental enrichment (EE) is a promising therapeutic strategy in improving metabolic and neuronal responses, especially due to its non-invasive nature. However, the exact mechanism underlying the sex-differential effects remains unclear. The aim of the current study was to investigate the effects of EE on metabolism, body composition, and behavioral phenotype based on sex. Long-term exposure to EE for 8 weeks induced metabolic changes and fat reduction. In response to the change in metabolism, the level of βHB were influenced by sex and EE possibly in accordance to the phases of estrogen cycle. The expression of β-hydroxybutyrate (βHB)-related genes and proteins such as monocarboxylate transporters, histone deacetylases (HDAC), and brain-derived neurotrophic factor (BDNF) were significantly regulated. In cerebral cortex and hippocampus, EE resulted in a significant increase in the level of βHB and a significant reduction in HDAC, consequently enhancing BDNF expression. Moreover, EE exerted significant effects on motor and cognitive behaviors, indicating a significant functional improvement in female mice under the condition that asserts the influence of estrogen cycle. Using an ovariectomized mice model, the effects of EE and estrogen treatment proved the hypothesis that EE upregulates β-hydroxybutyrate and BDNF underlying functional improvement in female mice. The above findings demonstrate that long-term exposure to EE can possibly alter metabolism by increasing the level of βHB, regulate the expression of βHB-related proteins, and improve behavioral function as reflected by motor and cognitive presentation following the changes in estrogen level. This finding may lead to a marked improvement in metabolism and neuroplasticity by EE and estrogen level., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer SK declared a shared affiliation with the authors to the handling editor at the time of review., (Copyright © 2022 Pyo, Kim, Hwang, Heo, Kim and Cho.)

This study proposes a method to valorize hazardous waste such as used COVID-19 face mask via catalytic gasification over Ni-loaded ZSM-5 type zeolites. The 25% Ni was found as an optimal loading on ZSM-5 in terms of H 2 production. Among different zeolites (ZSM-5(30), ZSM-5(80), ZSM-5(280), mesoporous (m)-ZSM-5(30), and HY(30)), 25% Ni/m-ZSM-5(30) led to the highest H 2 selectivity (45.04 vol%), most likely because of the highest Ni dispersion on the m-ZSM-5(30) surface, high porosity, and acid site density of the m-ZSM-5(30). The content of N-containing species (e.g., caprolactum and nitriles) in the gasification product was also reduced, when steam was used as gasifying agent, which is the source of potentially hazardous air pollutants (e.g., NO x ). The increase in the SiO 2 /Al 2 O 3 ratio resulted in lower tar conversion and lower H 2 generation. At comparable conditions, steam gasification of the mask led to ~15 vol% higher H 2 selectivity than air gasification. Overall, the Ni-loaded zeolite catalyst can not only suppress the formation of hazardous substances but also enhance the production of hydrogen from the hazardous waste material such as COVID-19 mask waste., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Laser cutting of intrusive rocks, including granite, gabbro, and diorite, is carried out in order to assess the cut characteristics through geometrical measurements, such as kerf width, melting width, and penetration depth. The absorption rate for each specimen at the wavelength of 1064 nm is measured using a spectrophotometer. A multimode fiber laser is used in this study with the power of 9 kW and different cutting speeds. Furthermore, nitrogen gas at 13 bar is applied as the assistant gas in order to remove the melted material effectively. As a result of the experiment, the relationship between the cutting speed and geometrical measurements is investigated. Furthermore, variations of penetration depth are performed in accordance with the number of laser cuts. In addition, through energy dispersive X-ray (EDX) element mapping, minerals that comprise the rocks are classified and characterized. Subsequently, the changes in the microstructure and chemical composition of each specimen, before and after laser cutting, are compared using scanning electron microscope (SEM) and EDX analyses. Experimental results demonstrate that the cutting characteristics vary, depending on the types of minerals that make up the rock. Based on a series of tests, it is identified that volume energy of more than 3.06E + 13 [Formula: see text] is required to fully cut intrusive rocks that have a thickness of 25 mm., (© 2022. The Author(s).)

Bio-heavy oil (BHO) is a renewable fuel, but its efficient use is problematic because its combustion may emit hazardous air pollutants (e.g., polycyclic aromatic hydrocarbon (PAH) compounds, NO x , and SO x ). Herein, catalytic fast pyrolysis over HZSM-5 zeolite was applied to upgrading BHO to drop-in fuel-range hydrocarbons with reduced contents of hazardous species such as PAH compounds and N- and S-containing species (NO x and SO x precursors). The effects of HZSM-5 desilication and linear low-density polyethylene (LLDPE) addition to the feedstock on hydrocarbon production were explored. The apparent activation energy for the thermal decomposition of BHO was up to 37.5% lowered by desilicated HZSM-5 (DeHZSM-5) compared with HZSM-5. Co-pyrolyzing LLDPE with BHO increased the content of drop-in fuel-range hydrocarbons and decreased the content of PAH compounds. The DeHZSM-5 was effective in producing drop-in fuel-range hydrocarbons from a mixture of BHO and LLDPE and suppressing the formation of N- and S-containing species and PAH compounds. The DeHZSM-5 enhanced the hydrocarbon production by up to 58.5% because of its enhanced porosity and high acid site density compared to its parent HZSM-5. This study experimentally validated that BHO can be upgraded to less hazardous fuel via catalytic fast co-pyrolysis with LLDPE over DeHZSM-5., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Today, sedentary lifestyles are very common for children. Therefore, maintaining a good posture while sitting is very important to prevent musculoskeletal disorders. To maintain a good posture, the formation of good postural habit must be encouraged through posture correction. However, long-term observation is required for effective posture correction. Additionally, posture correction is more effective when it is performed in real time., Objective: The goal of this study is to classify nine representative sitting postures of children by applying a machine learning technique using pressure distribution data according to the sitting postures., Methods: In this study, a customized film-type pressure sensor was developed and pressure distribution data from nine sitting postures was collected from seven to twelve year-old children. A convolutional neural network (CNN) was applied to classify the sitting postures and three experiments were conducted to evaluate the performance of the model in three applicable usage scenarios: usage by familiar identifiable users, usage by familiar, but unidentifiable users, and usage by unfamiliar users., Results: The results of our experiments revealed model accuracies of 99.66%, 99.40%, and 77.35%, respectively. When comparing the recall values for each posture, leaning left and leaning right postures had high recall values, but good posture, leaning forward, and crossed-legs postures had low recall values., Conclusion: The results of experiments indicated that CNN is an excellent classification method to classify the posture when the pressure distribution data is used as input data. This study is expected to contribute a development of system to aid in observing the natural sitting behavior of children and correcting poor posture in real time.

Performance of trunk rehabilitation exercises while sitting on movable surfaces with feet on the ground can increase trunk and leg muscle activations, and constraining the feet to move with the seat isolates control of the trunk. However, there are no detailed studies on the effects of these different leg supports on the trunk and leg muscle activations under unstable and forcefully perturbed seating conditions. We have recently devised a trunk rehabilitation robot that can generate unstable and forcefully perturbed sitting surfaces, and can be used with ground-mounted or seat-connected footrests. In this study, we have evaluated the differences in balance performance, trunk movement and muscle activation (trunk and legs) of fourteen healthy adults caused by the use of these different footrest configurations under the different seating scenarios. The center of pressure and trunk movement results show that the seat-connected footrest may be a more suitable choice for use in a balance recovery focused rehabilitation protocol, while the ground-mounted footrest may be a more suitable choice for a trunk movement focused rehabilitation protocol. Although it is difficult to make a clear selection between footrests due to the mixed trends observed in the muscle activation results, it appears that the seat-connected footrest may be preferable for use with the unstable seat as it causes greater muscle activations. Furthermore, the results provide limited evidence that targeting of a particular muscle group may be possible through careful selection of the seat and footrest conditions. Therefore, it may be possible to utilize the trunk rehabilitation robot to maximize the training outcomes for a wide range of patients through careful selection of training protocols.

Flexible tactile sensors capable of measuring mechanical stimuli via physical contact have attracted significant attention in the field of human-interactive systems. The utilization of tactile information can complement vision and/or sound interaction and provide new functionalities. Recent advancements in micro/nanotechnology, material science, and information technology have resulted in the development of high-performance tactile sensors that reach and even surpass the tactile sensing ability of human skin. Here, important advances in flexible tactile sensors over recent years are summarized, from sensor designs to system-level applications. This review focuses on the representative strategies based on design and material configurations for improving key performance parameters including sensitivity, detection range/linearity, response time/hysteresis, spatial resolution/crosstalk, multidirectional force detection, and insensitivity to other stimuli. System-level integration for practical applications beyond conceptual prototypes and promising applications, such as artificial electronic skin for robotics and prosthetics, wearable controllers for electronics, and bidirectional communication tools, are also discussed. Finally, perspectives on issues regarding further advances are provided., (© 2021 Wiley-VCH GmbH.)

In this paper, we propose a new monopolar microstrip antenna for a high-speed moving swarm sensor network. The proposed antenna shows an extremely thin substrate thickness supported with an omni-directional radiation pattern and wide operation frequency bandwidth. First, to achieve the low-profile monopolar microstrip antenna, the symmetrical center feeding network and the gap-coupled six arrayed patches which form a hexagonal microstrip radiator were utilized. The partially loaded ground-slots under the top patches were employed to improve the radiation performance and adjust the impedance bandwidth. Second, to obtain the broad bandwidth of the low-profile monopolar microstrip antenna, the degenerated non-fundamental TM 02 modes, that is, even and odd TM 02 modes, were carefully analyzed. To verify the feasibility of the degenerated TM 02 mode operation, the parametric study of the proposed antenna was theoretically investigated and implemented with the optimized parameter dimensions. Finally, the fabricated antenna showed a 0.254 mm-thick substrate and demonstrates 1.5-wavelength resonant monopolar radiation with broad impedance bandwidth of 855 MHz and its factional bandwidth of 15.24% at the resonant frequency of 5.57 GHz.

Background: Bone morphogenetic proteins (BMPs), which are members of the TGF-β superfamily, regulate bone remodeling by stimulating osteoblasts and osteoclasts. Although the association between osteitis and poor surgical outcomes is well known in patients with chronic rhinosinusitis (CRS), BMPs have not been fully investigated as potential biomarkers for the prognosis of CRS., Objective: Our aim was to investigate the role of BMPs in osteitis in patients with CRS with nasal polyps (NPs) (CRSwNPs), as well as associations between BMPs and inflammatory markers in sinonasal tissues from patients with CRSwNP., Methods: We investigated the expression of 6 BMPs (BMP-2, BMP-4, BMP-6, BMP-7, BMP-9, and BMP-10) and their cellular origins in NPs of human subjects by using immunohistochemistry and ELISA of NP tissues. Exploratory factor analysis was performed to identify associations between BMPs and inflammatory markers. Air-liquid interface cell culture of human nasal epithelial cells was performed to evaluate the induction of the epithelial-mesenchymal transition by BMPs., Results: Of the 6 BMPs studied, BMP-2 and BMP-7 were associated with refractoriness. Only BMP-2 concentrations were higher in patients with severe osteitis and advanced disease extent according to the computed tomography findings. Eosinophils and some macrophages were identified as cellular sources of BMP-2 in immunofluorescence analysis. An in vitro experiment revealed that BMP-2 induced epithelial-mesenchymal transition in air-liquid interface-cultured human nasal epithelial cells, particularly in a T H 2 milieu., Conclusion: BMP-2 could reflect the pathophysiology of mucosa and bone remodeling and may be a novel biomarker for refractory CRSwNP., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

While there have been remarkable improvements in the fabrication of suspended nanowires, placing a single nanowire at the desired location remains to be a challenging task. In this study, a simple method is proposed to fabricate suspended nanowires at desired locations using an electrospinning process and a designed microstructure. Using electrospun polymer fibers on the designed microstructure as a sacrificial template, various materials are deposited on it, and the electrospun fibers are selectively removed, leaving only nanowires of the deposited material. After the polymer fibers are removed, the remaining metal fibers agglomerate into a single nanowire. Throughout this process, including the removal of the polymer fibers, the samples are not exposed to high temperatures or chemicals, thereby allowing the formation of nanowires without oxidation or contamination. The diameter of the nanowire can be controlled in the electrospinning process, and a suspended Pd nanowire with a minimum diameter of 100 nm is fabricated. Additionally, a suspended single Pd nanowire-based H 2 gas sensor fabricated using the proposed process exhibits a highly sensitive response to H 2 gas., (© 2021 IOP Publishing Ltd.)

This numerical study investigates the structural performance of railway sleepers made of ultra high-performance concrete (UHPC). First, numerical concrete sleepers are developed, and the tensile stress-strain relationship obtained from the direct tension test on the UHPC coupons is used for the tensile constitutive model after applying a fiber orientation reduction factor. The numerical sleeper models are validated with the experimental data in terms of the force and crack-width relationship. Second, using the developed models, a parametric study is performed to investigate the performance of the UHPC sleepers while considering various design/mechanical/geometrical parameters: steel fiber contents, size of the cross-section, and diameter and strength of prestressing (PS) tendons. The simulation results indicate that the size of the cross-section has the most impacts on the performance, while the effect of yielding strengths of PS tendons is minimal among all the parameters. Engineers need to pay attention to efficiency and an economical factor when using a larger cross-section, since sleepers with larger cross-sections can be an over-designed sleeper. This study suggests an economical design factor for engineers to evaluate what combination of parameters would be economical designs.

In this study, we present a novel approach to the design of a conformal volumetric array composed of M × N convex subarrays in two orthogonal curvilinear directions for underwater acoustic imaging for mine detection. Our design targets require that the proposed array transducer has three-dimensional half-power beamwidths of 85° and 25° in either of its convex subarray parts, while also reaching a peak transmitting voltage response above 147 dB. The radiated sound pressure of the subarrays was independently derived as a function of their geometrical parameters. The resulting directional factors were then combined to analyze the beam profile of the entire array. The design was finally optimized to minimize the ripple level. To validate this theoretical design, the structure was modeled and analyzed using the finite element method. The comparison between the resulting beam pattern from the finite element analysis and the analytical computation showed an excellent compliance. The method advanced is a simple and systematic analytical model to facilitate the development of new conformal volumetric arrays for underwater mine detection.

White matter atrophy has been shown to precede the massive loss of striatal GABAergic neurons in Huntington's disease (HD). This study investigated the effects of in vivo expression of reprogramming factor octamer-binding transcription factor 4 (OCT4) on neural stem cell (NSC) niche activation in the subventricular zone (SVZ) and induction of cell fate specific to the microenvironment of HD. R6/2 mice randomly received adeno-associated virus 9 (AAV9)-OCT4, AAV9-Null, or phosphate-buffered saline into both lateral ventricles at 4 weeks of age. The AAV9-OCT4 group displayed significantly improved behavioral performance compared to the control groups. Following AAV9-OCT4 treatment, the number of newly generated NSCs and oligodendrocyte progenitor cells (OPCs) significantly increased in the SVZ, and the expression of OPC-related genes and glial cell-derived neurotrophic factor (GDNF) significantly increased. Further, amelioration of myelination deficits in the corpus callosum was observed through electron microscopy and magnetic resonance imaging, and striatal DARPP32 + GABAergic neurons significantly increased in the AAV9-OCT4 group. These results suggest that in situ expression of the reprogramming factor OCT4 in the SVZ induces OPC proliferation, thereby attenuating myelination deficits. Particularly, GDNF released by OPCs seems to induce striatal neuroprotection in HD, which explains the behavioral improvement in R6/2 mice overexpressing OCT4.

Osteoarthritis (OA) is a major degenerative joint disease. Oxidative stress and inflammation play key roles in the pathogenesis of OA. 3'-Sialyllactose (3'-SL) is derived from human milk and is known to regulate a variety of biological functions related to immune homeostasis. This study aimed to investigate the therapeutic mechanisms of 3'-SL in interleukin-1β (IL-1β)-treated SW1353 chondrocytic cells. 3'-SL potently suppressed IL-1β-induced oxidative stress by increasing the levels of enzymatic antioxidants. 3'-SL significantly reversed the IL-1β mediated expression levels of reactive oxygen species in IL-1β-stimulated chondrocytic cells. In addition, 3'-SL could reverse the increased levels of inflammatory markers such as nitrite, prostaglandin E2, inducible nitric oxide synthase, cyclooxygenase-2, IL-1β, and IL-6 in IL-1β-stimulated chondrocytic cells. Moreover, 3'-SL significantly inhibited the apoptotic process, as indicated by the downregulation of the pro-apoptotic protein Bax, upregulation of the anti-apoptotic protein Bcl-2 expression, and significant reduction in the number of TUNEL-positive cells in the IL-1β-treated chondrocytic cells. Furthermore, 3'-SL reversed cartilage destruction by decreasing the release of matrix metalloproteinases (MMP), such as MMP1, MMP3, and MMP13. In contrast, 3'-SL significantly increased the expression levels of matrix synthesis proteins, such as collagen II and aggrecan, in IL-1β-treated chondrocytic cells. 3'-SL dramatically suppressed the activation of mitogen-activated protein kinases (MAPK) and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathways, which are related to the pathogenesis of OA. Taken together, our data suggest that 3'-SL alleviates IL-1β-induced OA pathogenesis via inhibition of activated MAPK and PI3K/AKT/NF-κB signaling cascades with the downregulation of oxidative stress and inflammation. Therefore, 3'-SL has the potential to be used as a natural compound for OA therapy owing to its ability to activate the antioxidant defense system and suppress inflammatory responses., Competing Interests: Author LK was employed by the company GeneChem Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Baek, Jung, Pyo, Kim, Jo, Kim, Lee, Kim and Cho.)

Tonpilz transducers are desirable for their superior performance in underwater target detection and communication applications. Several design schemes to widen their bandwidth have been reported, but these schemes often involve a complex structure or arrangement of additional components. In this study, a simple design is proposed to improve the bandwidth of a multimode Tonpilz transducer by using a non-uniform drive section that consists of piezoelectric stacks of various thicknesses. The efficacy of the design is illustrated with a multimode Tonpilz transducer having three lead zirconate titanate (PZT) stacks of different thicknesses. A new equivalent circuit was developed to analyze the frequency response of the transducer incorporating the non-uniform drive section and was used for rigorous analysis of the effects of varying the position and thickness of the non-uniform stacks on the transmitting characteristics of the transducer. The validity of the design was verified through the fabrication and characterization of a prototype multimode Tonpilz transducer. The developed structure can be readily extended to an arbitrary number of stacks in the Tonpilz transducer with any number of PZT disks in each stack.

Hypoxic-ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O 2 hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Ca v 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Ca v 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Ca v 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE.

Although ultra high-performance concrete (UHPC) has great performance in strength and durability, it has a disadvantage in the environmental aspect; it contains a large amount of cement that is responsible for a high amount of CO 2 emissions from UHPC. Supplementary cementitious materials (SCMs), industrial by-products or naturally occurring materials can help relieve the environmental burden by reducing the amount of cement in UHPC. This paper reviews the effect of SCMs on the properties of UHPC in the aspects of material properties and environmental impacts. It was found that various kinds of SCMs have been used in UHPC in the literature and they can be classified as slag, fly ash, limestone powder, metakaolin, and others. The effects of each SCM are discussed mainly on the early age compressive strength, the late age compressive strength, the workability, and the shrinkage of UHPC. It can be concluded that various forms of SCMs were successfully applied to UHPC possessing the material requirement of UHPC such as compressive strength. Finally, the analysis on the environmental impact of the UHPC mix designs with the SCMs is provided using embodied CO 2 generated during the material production.

Tactile sensor arrays have attracted considerable attention for their use in diverse applications, such as advanced robotics and interactive human-machine interfaces. However, conventional tactile sensor arrays suffer from electrical crosstalk caused by current leakages between the tactile cells. The approaches that have been proposed thus far to overcome this issue require complex rectifier circuits or a serial fabrication process. This article reports a flexible tactile sensor array fabricated through a batch process using a mesh. A carbon nanotube-polydimethylsiloxane composite is used to form an array of sensing cells in the mesh through a simple "dip-coating" process and is cured into a concave shape. The contact area between the electrode and the composite changes significantly under pressure, resulting in an excellent sensitivity (5.61 kPa -1 ) over a wide range of pressure up to 600 kPa. The mesh separates the composite into the arranged sensing cells to prevent the electrical connection between adjacent cells and simultaneously connects each cell mechanically. Additionally, the sensor shows superior durability compared with previously reported tactile sensors because the mesh acts as a support beam. Furthermore, the tactile sensor array is successfully utilized as a Braille reader via information processing based on machine learning.

Parkinson's disease (PD) is a prevalent motor disease caused by the accumulation of mutated α-synuclein (α-Syn); however, its early stages are also characterized by non-motor symptoms, such as olfactory loss, cognitive decline, depression, and anxiety. The therapeutic effects of environmental enrichment (EE) on motor recovery have been reported, but its effects on non-motor symptoms remain unclear. Herein, we reveal the beneficial effects of EE on PD-related non-motor symptoms and changes in synaptic plasticity in the nucleus accumbens. To investigate its therapeutic effects in the early phase of PD, we randomly assigned eight-month-old mice overexpressing human A53T (hA53T) α-Syn to either the EE or standard condition groups for two months. Next, we performed behavioral tests and biochemical and histological analyses at 10 months of age. EE significantly alleviated locomotor hyperactivity and anxiety during the early stages of PD. It normalized the levels of tyrosine hydroxylase, phosphorylated and oligomeric α-Syn, and soluble N -ethylmaleimide-sensitive factor attachment protein receptor complex-forming proteins, including synaptosomal-associated protein, 25 kDa, syntaxin1, and vesicle-associated membrane protein 2 (VAMP2). Moreover, the interactions between VAMP2 and pSer129 α-Syn were markedly reduced following EE. The restoration of synaptic vesicle transportation status may underlie the neuroprotective effects of EE in hA53T α-Syn mice.

Splenic long-lived plasma cells are abnormally numerous and deleterious in systemic autoimmune diseases, yet how they accumulate remains poorly understood. We demonstrate here that a pathological role of spleen-derived CD11b + Gr-1 + myeloid cells (SDMCs) underpins the accumulation of splenic long-lived plasma cells in a lupus-prone model named sanroque. We found that SDMCs were progressively accumulated in sanroque mice from the early clinical phase. Transcriptome profiles revealed that SDMCs have a predominant shift toward an inflammatory phenotype relative to the bone marrow-derived counterparts and are distinct from neutrophils and monocytes. SDMCs were expanded in situ via splenic extramedullary myelopoiesis under the proinflammatory cytokine milieu during lupus progression. SDMCs promoted the development of IFN-γ-secreting Th1 and follicular helper T cells, thereby licensing CD4 + T cells to be pathologic activators of SDMCs and plasma cells. SDMCs also directly promoted the survival of plasma cells by providing B-cell activating factor of the TNF family. The frequency of SDMCs correlated with that of splenic long-lived plasma cells. Selective depletion of CD11b + Gr-1 + cells reduced autoantibody production in sanroque mice. Thus, our findings suggest that SDMCs expanded in situ establish a positive feedback loop with CD4 + T cells, leading to accumulation of long-lived plasma cells which exacerbates lupus autoimmunity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jang, Cho, Pyo, Nam and Youn.)

Underwater acoustic transducers are used to detect and track targets by using sound waves in underwater environments. To enhance the performance, they can be arranged in various formations to create arrays. However, acoustic interaction between the constituent channels of array transducers is inevitable, and it distorts their characteristics. In this study, the transmitting voltage response (TVR) spectrum of an acoustic planar array transducer is analyzed by considering the crosstalk between channels. The transmitting performance of an array transducer is frequently analyzed using the conventional finite element method (FEM). However, when the size of the array is large, the time and cost of computation using the FEM increase to almost prohibitive levels. To overcome this problem, a new equivalent circuit method (ECM) is developed to analyze the acoustic characteristics of an underwater array transducer. The ECM is validated by comparing its TVR spectrum with that analyzed using the FEM. After validation, the ECM is utilized to design the optimal structure of a planar array transducer having the broadest bandwidth. The sample analysis conducted using the ECM was approximately 1780 times faster than that by the FEM. Therefore the ECM developed in this work can facilitate the design of an underwater planar array transducer with a superior speed and efficiency compared with those achievable with the conventional numerical analysis methods such as the FEM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The positive effects of mesenchymal stem cells (MSCs) are primarily activated through molecular secretions known as paracrine activity, which regulates the function of various cell types including immune cells. Accumulating evidence shows that exosomes of soluble factors released from MSCs are potential alternative agents for stem cell-based therapy, although the exact underlying mechanism has not been elucidated. The purpose of this study was to evaluate the potential effects of exosomes produced by adipose-derived MSCs and to examine the changes in anti-inflammatory genes in concurrence with the polarization of M2 macrophages in cellular models ex vivo. Isolated exosomes were used to investigate the inflammatory modulation in pro-inflammatory cytokine-treated fibroblasts and THP-1 cells. The anti-inflammatory mRNA expression associated with M2 macrophages was significantly upregulated after exosome treatment in an interferon gamma and tumor necrosis factor alpha-treated inflammatory environment. Furthermore, melatonin-stimulated exosomes exerted superior anti-inflammatory modulation via exosomal miRNAs miR-34a, miR-124, and miR-135b, compared with exosomes. Our results indicate that melatonin-stimulated exosomes originating from adipose-derived MSCs are safe and efficient tools for regenerative medicine to treat inflammatory diseases., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 June Seok Heo et al.)

This experimental research investigates the mechanical properties of municipal plastic waste-based particulate composites reinforced with coal ash (CA), the by-product of thermal power plants, for sustainable railway sleepers. Six series of sustainable composites filled with inorganic mineral fillers, including CA, were prepared by a twin-screw extruder and a compression molding machine. The effect of mix design variables-such as filler type, contents and the particle size of the filler-on mechanical properties-including tensile, compression and flexural properties-and morphology were characterized. The scanning electron microscopy (SEM) was employed to examine the morphology of the composites, which revealed the uniform dispersion of fillers in the polymer matrix. The study results conclude that the recycled plastic-based composite with the addition of CA up to 60% is suitable for railway sleeper applications. This experimental study may provide new insight into the railway applications of the developed composites under service loading conditions including traffic loading and earthquake.

This experimental research investigated the applicability of the liquid crystal display (LCD) by-product of the refining process as a sustainable and alternative alkali activator for ground granulated blast-furnace slag (GGBFS) blended cement concrete. Three levels of binder replacement using the industrial by-product, and four water/binder ratios were considered in order to evaluate the effects of the replacement in fresh and hardened properties of the blended concrete. XRD and TG analyses confirmed that the by-product that contains abundant alkali compounds promotes the reactivity of GGBFS. The test results indicated that the incorporation of the by-product results in delayed setting and degraded workability due to the highly porous nature of the by-product, yet shows rapid early-age strength development of the blended concrete as conventional alkaline activators for GGBFS. These characteristics shed light on a simple yet effective and practical means of reusing the industrial by-product as an alternative alkaline activator.

The use of lightweight concrete has continuously increased because it has a primary benefit of reducing dead load in a concrete infrastructure. Various properties of lightweight concrete, such as compressive strength, elastic modulus, sound absorption performance, and thermal insulation, are highly related to its pore characteristics. Consequently, the identification of the characteristics of its pores is an important task. This study performs a comparative analysis for characterizing the pores in cementitious materials using three different testing methods: a water absorption test, microscopic image processing, and X-ray computed tomography (X-ray CT) analysis. For all 12 porous cementitious materials, conventional water absorption test was conducted to obtain their water permeable porosities. Using the microscopic image processing method, various characteristics of pores were identified in terms of the 2D pore ratio (i.e., ratio of pore area to total surface area), the pore size, and the number of pores in the cross-sectional area. The 3D tomographic image-based X-ray CT analysis was conducted for the selected samples to show the 3D pore ratio (i.e., ratio of pore volume to total volume), the pore size, the spatial distribution of pores along the height direction of specimen, and open and closed pores. Based on the experimental results, the relationships of oven-dried density with these porosities were identified. Research findings revealed that the complementary use of these testing methods is beneficial for analyzing the characteristics of pores in cementitious materials.

The applicability of Na-ion batteries is contingent on breakthroughs in alternative electrode materials that have high capacities and which are economically viable. Unfortunately, conventional graphite anodes for Li-ion battery systems do not allow Na-ion accommodation into their interlayer space owing to the large ionic radius and low stabilizing energy of Na in graphite. Here, we suggest a promising strategy for significantly increasing Na capacity by expanding the axial slab space of graphite. We successfully synthesized reconstructed graphite materials via self-assembly of negative graphite oxide (GO) flakes and Al cation (positive) pillars and by subsequent chemical reaction of the obtained Al-GO materials. Al pillars, atomically distributed in graphite interlayers, can extend the slab space by up to ∼7 Å, which is a 2-fold interlayer distance of pristine graphite. An exceptionally high capacity of 780 mAh/g is demonstrated for reconstructed graphite anodes with Al pillars, compared with rGO materials (210 mAh/g). We investigated the electrochemical reaction mechanism and structural changes associated with discharge and charge to emphasize the benefit of using reconstructed graphite as anodes in Na-ion batteries. Our strategy of modifying the interlayer distance by introducing metallic pillars between the layers can help address the low capacity of carbonaceous anodes.

This experimental research highlights the applicability of laser cutting to cement-based materials using multimode fiber lasers. A 9 kW multimode fiber laser is used, and the experimental variables are the water-to-cement ratio, laser speed, and material compositions such as cement paste, cement mortar and ultra high performance concrete (UHPC). The laser cutting performance on the cement-based materials is investigated in the downward laser direction. The kerf width and penetration depth of the cement-based materials are quantitatively evaluated with the parameters in the surface and cross section of the specimens after the laser cutting. Moreover, the material removal zone of each specimen is compared in terms of the penetration shapes in the cross-sectional view. Based on experimental observations, the interaction mechanism between the laser and cement-based materials is proposed.

Lateral pharyngeal wall appears to be a critical culprit of obstructive sleep apnea (OSA) subjects and relocation pharyngoplasty has been expected to be a promising surgical option to correct retropalatal circumferential narrowing in OSA patients. The purpose of our study is to evaluate the therapeutic outcomes of relocation pharyngoplasty and its clinical effectiveness in OSA patients with retropalatal circumferential narrowing. We performed relocation pharyngoplasty combined with nasal surgery in 133 OSA patients with the following characteristics: apnea-hypopnea index (AHI) over 10, retropalatal circumferential narrowing greater than grade I when awake, and redundant soft tissue around the lateral pharyngeal wall. The analysis of surgical success rate was performed with the data of 68 subjects who underwent pre and postoperative polysomnography. The objective success rate of relocation pharyngoplasty was 52.9%, and significant reduction of mean AHI with improvement of lowest SpO2 was seen in 69% of patients 3 months after the surgery. The median AHI was decreased from preoperative 37.3 to postoperative 21.4. Median lowest SpO2 changed from 78.4 to 84.1%. Total sleep time, daytime sleepiness, and visual analogue scale for snoring showed improvement as well. Postoperative complications including pain or bleeding were minimal in 133 subjects and a few patients complained of subtle taste loss. Our data demonstrate that relocation pharyngoplasty can be a favorable surgical option fighting against retropalatal circumferential narrowing.

Cement-based materials are the most prevalent construction materials, and the conventional cutting techniques are still mostly used for fabricating the materials. However, these conventional cutting methods could generate undesirable micro-cracks and remove unintentional structural sections. This experimental study aims to evaluate the effects of the new fabricating method using laser on the microstructural characteristics of the cement-based materials. The experimental variables are laser cutting speed, water to cement ratio and material compositions. In order to compare the microstructure before and after the laser interaction, the microstructure of the cut surface is observed through scanning electron microscopy/energy dispersive X-Ray (SEM/EDX). After the laser interaction, the Material Removed Zone (MRZ) and Heat Affected Zone (HAZ) are observed on the cut surface. In MRZ, it is found that the glassy layer is thickened by an increasing amount of silicate-based materials in cement-based materials. In addition, it concluded that the amount of silicate-based material mixed in the cement-based materials affects the laser cutting quality., Competing Interests: The authors declare no conflict of interest.

Objective: A high number of stroke survivors experience limitations in balance and gait abilities. Thus, an improvement in gait ability is an important goal in the rehabilitation of hemiplegic stroke survivors. This study aimed to investigate the effect of using the one-arm motorized walker, a hemi-walker developed to assist hemiplegic stroke survivors in gait training and activities of daily living, on the improvement in gait ability in hemiplegic stroke survivors., Methods: Eleven hemiplegic stroke survivors who met the inclusion criteria were included. The participants were instructed to walk thrice using traditional walking aids on a gait mat and then to walk thrice using the one-arm motorized walker. During each walk, spatiotemporal gait parameters, including velocity, cadence, step length, stride length, single support time, and double support time, were evaluated using a gait analysis system., Results: Velocity and cadence significantly increased when the participants walked using the one-arm motorized walker compared to those who used traditional walking aids (p< 0.05), whereas double support time significantly decreased for both the more affected and less affected sides (p< 0.05). However, no significant difference was observed in terms of step length and single support time., Conclusion: The one-arm motorized walker may have a positive effect on the improvement of gait ability in hemiplegic stroke survivors. It can be an effective walking aid for hemiplegic stroke survivors who experience difficulties in independent walking.

Background: Cognitive and emotional disturbances are common serious issues in patients with traumatic brain injury (TBI). However, predictors associated with neuropsychological functions were not consistent., Objective: To investigate factors affecting cognition and emotion in patients with TBI, we evaluated executive function, memory, and emotion based on injury severity and lesion location., Methods: Neuropsychological outcomes of 80 TBI patients were evaluated via Wisconsin Card Sorting Test (WCST), Color Trail Test (CTT), Controlled Oral Word Association Test (COWAT), Everyday Memory Questionnaire (EMQ), Geriatric Depression Scale (GDS), State-Trait Anxiety Inventory (STAI), and Agitated Behavior Scale (ABS). WCST, CTT, and COWAT assessed executive function; EMQ assessed everyday memory; and GDS, STAI, and ABS assessed emotion. Patients were categorized according to lateralization of lesion and existence of frontal lobe injury., Results: Patients with longer duration of loss of consciousness (LOC) showed more severe deficits in everyday memory and agitated behaviors. The frontal lesion group showed poorer performance in executive function and higher agitation than the non-frontal lesion group. Patients with bilateral frontal lesion showed greater deficits in executive function and were more depressed than unilateral frontal lesion groups. Especially in those unilateral frontal lesion groups, right side frontal lesion group was worse on executive function than left side frontal lesion group., Conclusions: Duration of LOC and lesion location are main parameters affecting executive function, everyday memory, and emotion in neuropsychological outcomes following TBI, suggesting that these parameters need to be considered for cognitive rehabilitation interventions.

Mesenchymal stem cells (MSCs) are capable of differentiating into other cell types and exhibit immunomodulatory effects. MSCs are affected by several intrinsic and extrinsic signaling modulators, including growth factors, cytokines, extracellular matrix and hormones. Melatonin, produced by the pineal gland, is a hormone that regulates sleep cycles. Recent studies have shown that melatonin improves the therapeutic effects of stem cells. The present study aimed to investigate whether melatonin enhances the biological activities of human adipose‑derived MSCs. The results demonstrated that treatment with melatonin promoted cell proliferation by inducing SRY‑box transcription factor 2 gene expression and preventing replicative senescence. In addition, melatonin exerted anti‑adipogenic effects on MSCs. PCR analysis revealed that the expression of the CCAAT enhancer binding protein a gene, a key transcription factor in adipogenesis, was decreased following melatonin treatment, resulting in reduced adipogenic differentiation in an in vitro assay. The present study also examined the effect of melatonin on the immunomodulatory response using a co‑culture system of human peripheral blood mononuclear cells and MSCs. Activated T cells were strongly inhibited following melatonin exposure compared with those in the control group. Finally, the favorable effects of melatonin on MSCs were confirmed using luzindole, a selective melatonin receptor antagonist. The proliferation‑promoting, anti‑inflammatory effects of melatonin suggested that melatonin‑treated MSCs may be used for effective cell therapy.

Underwater sensors that detect the distance and direction of acoustic sources are critical for surveillance monitoring and target detection in the water. Here, we propose an axial vector sensor that utilizes a small (~1 cm 3 ) compressive-type piezoelectric accelerometer using piezoelectric single crystals. Initially, finite element analysis (FEA) was used to optimize the structure that comprised piezoelectric Pb(Mb 1/3 Nb 2/3 )O 3 -28%PbTiO 3 single crystals on a tungsten seismic mass. The receiving voltage sensitivity (RVS) was enhanced through geometric optimization of the thickness and sensing area of the piezoelectric material and the seismic mass. The estimated maximum RVS of the optimized vector sensor was -212 dB. FEA simulations and practical measurements were used to verify the directivity of the vector sensor design, which exhibited a dipole pattern. The dipole beam pattern was used to obtain cardioid patterns using the simulated and measured results for comparison. The results clearly showed the feasibility of using the proposed piezoelectric single-crystal accelerometer for a compressive-type vector sensor.

Two-dimensional (2D) nanomaterials have been extensively explored as promising candidates for gas sensing due to their high surface-to-volume ratio. Among many 2D nanomaterials, molybdenum disulfide (MoS 2 ) is known to be functional in detecting harmful gases at room temperature; therefore, it has been actively studied as a gas sensing material. However, there has been a limitation in recovering the original signal from reacted MoS 2 after exposure to the target gas. This work demonstrates the recovery of the initial resistance of reacted chemical vapor deposition-grown MoS 2 by illuminating it with a UV light-emitting diode (LED). A novel mechanism involving photo-generated electron-hole pairs in MoS 2 is proposed and experimentally verified. The fabricated sensor detects nitrogen dioxide (NO 2 ) and distinguishes between concentrations from 1 to 10 ppm with the proposed recovery process. Reversible detection after repeated exposure to 5 ppm NO 2 over eight cycles is achieved through UV-LED illumination for a short time during the recovery process, while the identical sensor without UV illumination shows a transitional response at each cycle. To apply a low cost gas sensing solution at room temperature, visible light LEDs are also used to recover the resistance of the reacted MoS 2 .

The elderly population in many countries has been rising rapidly, and falls are a serious event many elderly people experience. Assistive equipment is actively used to reduce falls among elderly people. Popular types of assistive equipment include canes, electric wheelchairs, and wheeled walkers. Wheeled walkers support the body of elderly people, making their gait comfortable as they age or recover from injuries. Wheeled walkers may be equipped with hand brakes; however, frail older people may experience difficulty using such hand brakes, as they require force to operate. Thus, in the present study, a braking method using a wire connected to a user's belt or clothes was designed and implemented; if the tension of the wire connecting the safety device and the user exceeds a critical value, the wheeled walker brakes, which can prevent the rapid motion of walkers. Two feasibility tests of the wheeled walker with the braking device were conducted: one with 10 healthy adults in their 20s and the other with 10 elderly people over 65 years of age; the tests measured the braking time and speed control using a speed measuring device. The results of the first and second feasibility tests demonstrated that the average braking time of participants was 50.3 ms and 50.7 ms, respectively. All participants in the feasibility tests succeeded in the speed control test. Thus, based on the results, the braking device on the wheeled walker worked properly.

We present a triboelectric energy harvester fabricated with a simple electrospinning process of polyvinylidene fluoride/polyurethane polymers on conductive fabric. This electrospinning process provides higher electrical power output and hydrophobicity driven humidity resistance compared to flat polymer energy harvesters. By using conductive fabric as collector and electrode, the device could retain air permeability and flexibility. The triboelectric energy harvester exhibits a high open-circuit voltage of 45.1 V (at a compressive contact force of 20 N and relative humidity (RH) of 20%), humidity resistance (maintains about 40% of the open-circuit voltage at RH of 80%) and air permeability without deteriorating the air permeability of the fabric. Its durability was tested and shows no significant degradation of electrical output throughout 324,000 cycles of operation. This work suggests an approach for human energy harvesting in textile form with electrospun nanofibers as the contact surfaces of a triboelectric energy harvester.