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Specific targeting of tumor cells is a key to achieving high therapeutic efficacy while minimizing off-target side effects. As a general approach to targeting diverse tumor cells, considerable attention has been paid to the tumor microenvironment, particularly its slightly acidic pH (6.5–6.8). However, existing pH-sensitive nanomaterials, based on organic polymers and proteins, often lack sufficient pH sensitivity and specificity. Here, we demonstrate a strategy to construct a pH-responsive protein assembly through clustering of a single amino acid repeat as a charge-tunable moiety. As a proof of concept, a histidine peptide with varying lengths was displayed on the surface of a ferritin assembly composed of 24 subunits by genetic fusion to a subunit. The resulting self-assembled ferritin particles, termed “pHerricle (pH-responsive ferritin particle)”, were shown to exhibit a specific binding to tumor cells in response to pH changes through cooperative effects of histidine peptides. Increasing the histidine peptide length from 0 to 12 residues increased the pHerricle’s cell-binding capacity by 21-fold and allowed modulation of the targetable pH range. General applicability as a tumor cell-targeting platform was shown by specific delivery of a cytotoxic cargo by the pHerricle into tumor cells of various origins in a pH-dependent manner.

The article highlights the emergence and evolution of live music clubs in Hongdae, which became essential platforms for indie bands and a driving force behind Korea's indie music scene since the early 1990s, offering alternative entertainment to mainstream K-pop. Topics include the historical significance of Hongdae's live music venues, the impact of these clubs on the indie music culture, and the ongoing transformation of the music scene in response to commercialization.

In this work, we reveal the role of non-covalent interactions, which are known to play important roles in supramolecular phenomena, in achieving efficient perovskite surface and grain boundary passivation. By using a series of pseudohalides, we find that trifluoroacetate (TFA−) provides the strongest binding to iodide vacancies by means of non-covalent hydrogen bonding and dispersion interactions. By exploiting additional non-covalent dispersion and hydrophobic interactions in aromatic 3,3-diphenylpropylammonium (DPA+), we present a dual-ion passivation strategy that not only minimizes the non-radiative recombination center and local chemical inhomogeneities but also induces preferentially oriented growth of α-FAPbI3lattice. This leads to an outstanding power conversion efficiency (PCE) of 25.63% with an exceptional open-circuit voltage of 1.191 V in a perovskite solar cell with a small area, while perovskite solar mini modules with aperture areas of 25 and 64 cm2achieved PCE of 22.47% (quasi-steady-state [QSS]-certified 20.50%) and 20.88%, respectively, with outstanding stability under high-humidity conditions.

Railways, as one of the representative mass transit systems, are vulnerable to highly contagious respiratory diseases due to their operation in densely populated environments. Notably, the current convective heating system creates an environment susceptible to virus transmission within railway vehicles. To improve this situation, there have been attempts to introduce radiant heating systems to reduce the risk of virus transmission and create a comfortable indoor environment. Previous studies focused on developing radiant heating composite material for railway vehicles by incorporating a carbon fiber heating element within a glass fiber composite to enable heat generation through joule heating. However, this development was limited to the specimen level. In contrast, this study aims to demonstrate their applicability and performance for actual railway vehicle parts at the component level. Specifically, resin flow and manufacturability were analyzed to assess applicability to railway vehicles. Additionally, heating performance and heat flow characteristics were evaluated to determine heating effects. Based on these results, it is anticipated that the application of multifunctional composite materials in the railway industry will improve the vulnerability to winter viruses and indoor environments and expand the utilization of multifunctional composite materials in various fields.

Interest in the exploration of renewable energy sources is increasing due to energy scarcity and growing environmental concerns. Biodiesel is one of the most potential renewable alternatives to fossil fuels and is commonly manufactured by esterification of refined vegetable oils with heterogeneous acid/base catalysts. In this study, we have systematically investigated various acid-doped graphitic carbon nitride (g-C3N4)-based heterogeneous catalysts for biodiesel production using first-principles calculations. The reaction pathways for catalyzing the esterification of free fatty acids (FFA) over these catalysts were analyzed to achieve the formation of methyl butyrate (biodiesel). The calculated results showed a significant reduction in the kinetic energy barriers (to 0.90 eV and 0.41 eV) in the presence of acid-doped (OH and Al–OH) g-C3N4catalysts, in contrast to the kinetically unfavorable esterification process using the commercial Amberlyst-15 catalyst. Additionally, the enhanced product selectivity was achieved by the Al–OH-doped g-C3N4catalyst, attributed to strong orbital hybridization between the O-2p orbitals of the potential-determining intermediate and the Al-3p orbital of the acid catalyst in the VB region. In addition, the greater electron density redistribution between the stable tetrahedral intermediate (TS) and Al–OH-doped g-C3N4catalysts demonstrated an improvement in the kinetics of the esterification reaction. This study emphasizes the importance of incorporating organic acid dopants into g-C3N4catalysts, revealing their significant impact on the electronic structure and reaction barriers during the esterification process. The present findings open up new perspectives for the design of superior heterogeneous catalysts for efficient biodiesel production application.

To address the intermittency of renewable energy sources, global warming, and increasing load demands, this paper proposes the optimal sizing of a multi-energy microgrid (MEMG) consisting of electrical, thermal, cooling, and hydrogen networks. The system integrates multi-energy storage and EVs along with the resilience load to facilitate a robust operation scheme. The paper introduces an improved resilience backup mechanism for EVs using hybrid storage. Then, random samples for stochastic parameters are generated with Monte Carlo Simulations (MCS). To this end, a mixed-integer linear programming-based model is developed to minimize cost, emissions, and load shed. Then, a CPLEX solver is applied to solve it efficiently. The optimal MEMG with the hydrogen network reduces cost by 4% and emissions by 40%. The case study validates that hybrid storage (BES-HST-TST) can effectively reduce the electricity grid purchase to zero, making MEMG self-sufficient while yielding the least annual system cost (ASC) of 3855562$and decreasing emissions to 8385 kg, resulting in economic savings, environmental sustainability, and increased utilization of renewables. Notably, V2G can save 0.7546% of MEMG extra cost incurred due to EVs integration and significantly reduces CO2 emissions by 4%. A novel finding is that the proposed hybrid storage backup mechanism can effectively minimize the extra cost of keeping the resilience load by retaining 31.46% of backup in hydrogen form. It mitigates risk associated with power outages while achieving the least ASC of 3858933$and CO2 emissions of 8043 kg. These results can help realize a green, cost-effective, and efficient energy system.

Here, we present triple sets of wavefront modulation by proposing quarter‐waveplate‐based GPL (QWP GPL). We demonstrate nine depth‐switchable AR imaging functions with a bi‐stack condition of the QWP GPL modules. The presented QWP‐based GPL module scheme is advantageous for increasing depth‐switchable layers without increasing the switchable optic units required. In addition, the AR display optics based on the QWP GPL module can further improve form‐factor issues and AR imaging properties.

The hydrogen production from combustible waste is attracting attention because of the increasing interest in clean and renewable hydrogen production. To produce hydrogen from combustible waste, gasification and water gas shift reaction processes are required. Syngas, which mainly consists of hydrogen and carbon monoxide, is generated by gasification of combustible waste. The water gas shift reaction is applied to produce additional hydrogen from carbon monoxide in waste-derived syngas. The performance of catalysts is important to achieve reasonable process efficiency. Co-based catalysts were applied to the water gas shift reaction because Co has significant capability for CO oxidation and high reaction rates when it is used as an active metal. However, it was necessary to enhance the stability of Co-based catalysts. Here, different transition metal oxides (TiO2, ZrO2, V2O5, and Nb2O5) are used as promoters to enhance the Co-CeO2catalyst performance. To investigate the effects of promoters on the catalytic performance, various properties are characterized. According to the analysis results, the physicochemical properties, which determine the catalytic performance, were influenced by the addition of transition metal oxides. Among the synthesized catalysts, the Nb2O5-promoted Co-CeO2catalyst exhibited the best catalytic performance. As a result, the Nb2O5promoter is the most effective to improve the catalytic activity and stability of the Co-CeO2catalyst for high-temperature water gas shift reaction to produce hydrogen from waste-derived syngas. The higher CO conversion is related to the numerous oxygen vacancies and high Co dispersion, while stability is related to strong interactions between Co and the support. These findings are expected to aid the development of catalysts by confirming physicochemical properties relating with catalytic performance.

The flashlight sintering characteristics of inkjet-printed nanosized copper ink on paper substrates with varying pattern widths and intervals were studied. The copper nano particles (CNPs) synthesized using vapor self-assembled multilayer (VSAM) method to prevent oxidation, were produced with ink and patterned on a paper substrate through inkjet printing. The width and interval of the Cu patterns were varied from 350 to 550 μm to investigate the flashlight sintering tendency. It was confirmed that the Cu pattern resistivity decreased as the width of the Cu pattern increased, with decreasing interval between the Cu patterns. For the Cu pattern with the largest width and narrowest interval, the lowest specific resistivity was 6.43 × 10–6Ω∙m. For auxiliary heating at 80 °C, the lowest resistivity of the Cu pattern was 7.10 × 10–6Ω∙m with improved adhesion to the substrate, and this resistivity was 6.2 times lower than that without auxiliary heating. The temperature gradient of the CNP pattern during the flashlight sintering process was predicted using custom made simulation program. Therefore, the experiments and simulations confirmed that the wider the width and the narrower the interval between patterns, the flashlight sintering characteristics improved through higher heat generation by minimizing heat spreading.

With the popularity of the internet and the rapid growth of user-generated content facilitated by various platforms of social media, online reviews have become an important source of information for customers to obtain product information and affect their purchasing decisions in the service industry. The accelerated development of bed-and-breakfasts (B&Bs) in the context of a rural revitalization strategy implies a shift in people’s demand from standardized to personalized accommodation. From the first establishment to the well-developed industry, the competition among diverse B&Bs is getting fiercer, and it is essential for business operators to understand their customers deeply and timely. Therefore, online reviews posted by customers freely and in real time were adopted to explore key dimensions reflecting customer experience and examine their relationship with customer satisfaction, which is a vital antecedent for customer loyalty, repurchase intention, etc. A total of 8,691 reviews from Ctrip were collected and then used for extracting relative insights and cognition by qualitative and quantitative analysis. Consequently, several implications for future research development and practical application are discussed for service promotion and development of the B&B industry.Funding:This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF-2022S1A5A2A03052622).

The electrochemical conversion of oxygen holds great promise in the development of sustainable energy for various applications, such as water electrolysis, regenerative fuel cells, and rechargeable metal-air batteries. Oxygen electrocatalysts are needed that are both highly efficient and affordable, since they can serve as alternatives to costly precious-metal-based catalysts. This aspect is particularly significant for their practical implementation on a large scale in the future. Herein, highly porous polyhedron-entrapped metal–organic framework (MOF)-assisted CoTe2/MnTe2heterostructure one-dimensional nanorods were initially synthesized using a simple hydrothermal strategy and then transformed into ZIF-67 followed by tellurization which was used as a bifunctional electrocatalyst for both the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The designed MOF CoTe2/MnTe2nanorod electrocatalyst exhibited superior activity for both OER (η = 220 mV@ 10 mA cm–2) and ORR (E1/2= 0.81 V vs RHE) and outstanding stability. The exceptional achievement could be primarily credited to the porous structure, interconnected designs, and deliberately created deficiencies that enhanced the electrocatalytic activity for the OER/ORR. This improvement was predominantly due to the enhanced electrochemical surface area and charge transfer inherent in the materials. Therefore, this simple and cost-effective method can be used to produce highly active bifunctional oxygen electrocatalysts.

The prompt visual response is considered to be a highly intuitive tenet among sensors. Therefore, plasmomechanical strain sensors, which exhibit dynamic structural color changes, have recently been developed by using mechanical stimulus-based elastomeric substrates for wearable sensors. However, the reported plasmomechanical strain sensors either lack directional sensitivity or require complex signal processing and device design strategies to ensure anisotropic optical responses. To the best of our knowledge, there have been no reports on utilizing anisotropic mechanical substrates to obtain directional optical responses. Herein, we propose an anisotropic plasmomechanical sensor to distinguish between the applied force direction and the force magnitude. We employ a simple strain-engineered topological elastomer to mechanically transform closely packed metallic nanoparticles (NPs) into anisotropic directional rearrangements depending on the applied force direction. The proposed structure consists of a heterogeneous-modulus elastomer that exhibits a highly direction-dependent Poisson effect owing to the periodically line-patterned local strain redistribution occurring due to the same magnitude of applied external force. Consequently, the reorientation of the self-assembled gold (Au)-NP array manifests dual anisotropy, i.e., force- and polarization-direction-dependent plasmonic coupling. The cost-effectiveness and simple design of our proposed heterogeneous-modulus platform pave the way for numerous optical applications based on dynamic transformation and topological inhomogeneities.

We present a novel augmented reality (AR) display system utilizing a holographic optical element (HOE)-based approach, featuring seamless switching between three-dimensional (3D) and two-dimensional (2D) modes through a liquid-crystalline microlens array (LC-MLA). The proposed system aims to capture and present comprehensive spatial information on real-world objects. The LC-MLA is customized to suit the purpose of the proposed system, and its functionality seamlessly switches via an electrical polarizer, allowing users to effortlessly toggle between modes by simply pressing a switch button. An integrated control system automates corresponding tasks based on the selected mode. In 2D mode, the captured image is directly displayed, while in 3D mode, an elemental image array (EIA) is generated and reconstructed into a 3D image, through the LC-MLA. To ensure optimal performance for the proposed system, a custom-fabricated LC-MLA, and full-color HOE combiner have been developed. Additionally, we designed and implemented a bespoke integrated control system that synchronizes and interconnects the main devices seamlessly.

Tauopathy is characterized by the abnormal aggregation of tau proteins. In order to develop drugs for tauopathies, a variety of different therapeutic strategies have been investigated. Synapse loss is a hallmark of tauopathies and is reportedly related to cognitive impairment in Alzheimer's disease as well. Emerging evidence suggests that pathogenic tau species are linked to synaptic dysfunction and synapse loss in tauopathies. As such, a potential therapeutic approach to ameliorate synaptic dysfunction and counteract synaptic loss due to pathogenic tau holds promise. This review highlights the pathological links between tau pathology and synaptic integrity and current efforts to develop therapeutics rescuing synaptic dysfunction for tauopathies, which will help to understand the association between tau and synapses and develop disease‐modifying drugs for tauopathies.

In this article, closed-form characterization of anisotropic polymer network liquid-crystal (PNLC) for reconfigurable RF devices at the millimeter-wave (mmWave) band is achieved. For the first time, the complex permittivity of the PNLC has been extracted for various doping conditions of reactive mesogen used in the polymer network at the mmWave band. Anisotropic constitutive parameters at the two extreme states of the PNLC can be obtained through a waveguide (WG). A $1 \times 2$ reflectarray simple cell in the WG enables the establishment of an equivalent circuit (EQ) for an infinite cell array, providing exact modeling for de-embedding. The PNLC has an attractive property compared with pristine nematic liquid crystals (NLCs) owing to its significantly enhanced dynamic switching characteristics. In the mmWave band, the physical cell gap of the liquid crystal (LC) inevitably increases to achieve RF performance, resulting in slow dynamic speed. However, studies on the characterization of PNLCs at the mmWave band are limited, and their evaluation methodologies are inaccurate. The fabricated cell requires no biasing circuit to achieve two extreme phase states, owing to its prealigned layer. With the proposed novel method, constitutive parameters of other LC types, modified by doping approaches for RF performance can be precisely extracted and predicted.

A two-stage electrostatic precipitator (ESP) was developed using carbon brush ionizers and lightweight plastic electrodes to be used in an air handling unit (AHU). In a pilot study, the developed ESP emitted near-zero ozone (<10 ppbv) and achieved a PM2.5 collection efficiency higher than 90%. Theoretical analysis revealed that diffusion charging was as important as field charging in the particle charging mechanism. Based on the results of the pilot study, a real AHU of Yuseong Oncheon subway station, South Korea, was retrofitted with the developed ESP. In the field study, a flow distributor was required to achieve uniform flow and minimize the spatial standard deviation of the air flow velocity. Compared to a filter with a minimum efficiency reporting value (MERV) = 14, typically used for particle removal, the pressure drop decreased from 157.1 to 15.2 Pa, and the PM2.5 collection efficiency increased from 72.7% to 75.0% by the retrofitting of the AHU. The modified quality factor improved more than three-fold, and the required power consumption to operate the device and the fan decreased from 2.49 to 0.85 kW. During ESP operation, the indoor ozone concentration increased by only 1.1 ppbv, whereas the outdoor ozone concentration increased by 30 ppbv. Thus, ESP operation in this study barely increased the indoor ozone concentration.

Intense pulsed light (IPL) sintering or annealing technology has attracted tremendous attention from many researchers and a variety of industries owing to its unique features. In IPL process, the pulsed white flash-light from xenon lamp is irradiated on the target materials and converts it to the desired conductive layer. The IPL process is ambient condition and room temperature process. The irradiated IPL on the materials can induce an extremely quick heating (several milliseconds) to the certain temperature by the synergetic opto-chemical, opto-thermal phenomena without damage on the low temperature substrates such as polymer and paper. The exact mechanisms of these opto-synergetic phenomena has been intensively studied by many researchers for a decade. Also, the applications of IPL techniques have become more extensive in printed electronics. In this review, we summarized the brief history and various applications of the intense pulsed light technology to conductive electrodes as well as several applications. The IPL process can provide a paved route to revolutionary eco-benign and low-cost manufacturing process for many applications.

In the recent study of proton therapy, the expectation of the normal tissue-sparing effect of the proton minibeam radiation therapy (pMBRT) using a multi-slit collimator (MSC) is increasing. We designed and conducted animal experiments to verify the sparing effect on normal tissues. Proton beam irradiation was carried out on two groups of mice except a control group (0 Gy). One group was irradiated with a conventional broad beam, and the other with a minibeam. A dose of 8.5 Gy was delivered to both femurs of mice in every group. In the pMBRT group, the survival rate of bone marrow cells was significantly improved as compared to the conventional broad beam group. The survival rate in the minibeam group was 2.5 times higher. In conclusion, the pMBRT has been strongly proven to have a superior tissue-sparing effect than the conventional broad beam.

While neural rendering approaches facilitate photo-realistic rendering in novel view synthesis tasks, the challenge of high-resolution rendering persists due to the substantial costs associated with acquiring and training data. Recently, several studies have been proposed that render high-resolution scenes by either super-sampling points or using reference images, aiming to restore details in low-resolution (LR) images. However, super-sampling is computationally expensive, and methods with reference images require high-resolution (HR) images for inference. In this letter, we propose a novel super-resolution (SR) neural radiance field (NeRF) framework for high-fidelity novel view synthesis. To address the representation of high-fidelity HR images from the captured LR images, we learn a mapping function that maps LR rendering images to the Fourier space to restore insufficient high frequency details and render HR images at higher resolution. Experiments demonstrate that our results are quantitatively and qualitatively better than those of the existing SR methods in novel view synthesis. By visualizing the estimated dominant frequency components, we provide visual interpretations of the performance improvement.

Graphical abstract:

A composite B-pillar was designed and manufactured by design optimization combined with an impact analysis. A carbon-fiber-reinforced plastic (CFRP) was used for the reinforcement part of the B-pillar assembly to substitute the conventional steel materials for reducing the weight of vehicle. To maximize the impact performance by finite element method, the equivalent static loads method was used. The shape, stacking sequence, and thickness of the CFRP reinforcement were optimized to minimize the deflection profile for improving the crashworthiness while reducing the weight. The designed CFRP B-pillar was manufactured and its performance was evaluated by a drop weight test. As a result, the CFRP B-pillar exhibited an improved impact performance and reduced weight compared to those of the conventional steel B-pillar.

The presence of particulate matter (PM), which may contain airborne pathogens, raises significant concerns because of its ability to facilitate the transmission of diseases through aerosols. In this study, we developed an antiviral electrostatic precipitator (ESP) with commercially available antiviral films. We applied antiviral surfaces on ESP collection plates and demonstrated that it was effective to remove and inactivate aerosolized viruses in a two-stage ESP. For practical applicability and versatility in indoor air management, the near-zero ozone generation system was applied on the ESP, and four types of viruses, namely MS2 bacteriophage, H1N1, HCoV-229E and -OC43, were selected as suitable surrogates for human and animal respiratory viruses such as SARS-CoV-2. After collection of aerosolized viruses on antiviral surfaces for 30 min, the survivability of the collected viruses was remarkably decreased. We are confident that the findings of this study will demonstrate the viability of ESPs as a promising indoor/private air pollution control technology, boasting exceptional bioaerosol removal and inactivation efficiency. In addition, we aspire for our research to contribute significantly to the prevention of future outbreaks such as COVID-19 by providing a solid foundation for effective measures.

Abstract: In this study, mechanical properties and moisture related hygroscopic characteristics of semi-crystalline polypropylene (PP) were investigated via molecular dynamics (MD) simulations and experiments with respect to degree of crystallinity. To control the degree of crystallinity, experimental samples were treated by an annealing process while MD models were constructed through combination of crystalline and amorphous layers. In order to evaluate crystal structure and calculate degree of crystallinity for the experimental samples, X-ray diffraction (XRD) and differential scanning calorimeter (DSC) measurements were conducted. For comparison with the experimental samples, an XRD simulation was performed for the MD models. Then, the mechanical and hygroscopic properties such as elastic modulus and moisture saturation amount were studied with respect to the degree of crystallinity through experiment and MD simulation. It was found that the effects of the degree of crystallinity on the hygro-mechanical properties of the semi-crystalline PP can be predicted from the developed MD simulation. It is expected that the simulation approach developed in our study can be widely used to predict the characteristics of the semi-crystalline PP with varying degree of crystallinity. Graphic Abstract:

An intense pulsed light (IPL) was irradiated for the sintering of screen-printed copper (Cu) nano/micro-paste patterns on a polyimide substrate. The pattern widths and intervals affect the sintering behavior owing to the opto-thermal relationship during IPL irradiation. The temperature histories of the patterns during the IPL sintering process were predicted using a self-developed heat transfer simulation program. By comparing the experimental and simulation results, the tendency according to the size of the Cu pattern was confirmed. At the same IPL irradiation energy, the wider the pattern and the narrower the interval between the patterns, the higher the heat generated. To demonstrate the tendency, in situ resistance monitoring of the Cu patterns was conducted and their microscopic structures were investigated using a scanning electron microscope. Through the tendency of IPL sintering according to the widths and intervals of the Cu pattern, guidelines of IPL sintering process for electrodes with multi-size pattern were suggested: A dummy pattern was added between the existing digitizer patterns to achieve uniform sintering in all regions. When IPL sintering was conducted with the dummy patterns, the uniformly sintered line resistance could be obtained in entire areas of the digitizer pattern.

Graphical abstract:

Autonomous car racing competitions have become widespread across many countries and events, taking inspiration from renowned motorsports like Formula 1 and IndyCar, among others. Similar to how traditional motorsports have fueled advancements in automotive technology, researchers and students are now anticipating similar contributions from autonomous car racing competitions. Betz et al. have provided a comprehensive review of the current landscape of autonomous car racing in [1]. These competitions feature a diverse range of robot cars, varying in scale from 1:10 to full-scale (refer to Table 1 for specifics). The size differences also extend to the sensory and computing systems employed. While many of these events are tailored for educational purposes, targeting students from high school to postgraduate programs, it is noted that smaller-scale hardware systems may not necessarily utilize the same sensory and computing systems as their real-scale counterparts. This, however, does not imply that the technical challenges in algorithm and program development are any less demanding than those encountered in full-scale or near full-scale cases. The variations in sensory, computing, and hardware resources due to the size differences may give rise to distinct technical problems not encountered by autonomous cars navigating real-world road environments. Nevertheless, fundamental issues, such as planning, motion control, and real-time recognition with onboard systems are common for both scales.

This study presents a Pd(II)-catalyzed method for the β-C(sp3)–H arylation of N-Cbz- or N-Fmoc-protected N-methyl alanines, providing ready access to building blocks for N-methylated peptide synthesis. For this transformation, the native carboxylate was exploited as the directing group, attributing its success to the use of a monoprotected amino-pyridine ligand. Its synthetic utility was demonstrated by facile generation of nine analogues of the naturally occurring N-methylated cyclic peptide cycloaspeptide A.

In recent years, wearable heaters have attracted widespread attention for applications in personal heating systems and healthcare management, such as thermotherapy of textiles/clothing. In addition, flexible gas sensors are important components of wearable electronic devices used for human safety and healthcare applications. However, the current low flexibility and poor stability of the materials limit their use. In this paper, among various textile materials, the carbon fabric based high-efficiency flexible heater with its own excellent conductivity, which does not contain additives from the manufacturing state, and a sensor using the same. In order to evaluate the performance of the heater, the heating temperature and power according to the applied voltage were analyzed. Also, the temperature distribution of the carbon fabric was observed using a thermal camera. The highly flexible fabric heater is based on a uniformly interconnected carbon fiber network that efficiently and quickly heats the heater with low input power. In addition, it presents a new carbon fabric gas sensor composed of pure carbon fiber itself without additives. The carbon fabric shows a sensitive response to NO2 (24.4%@5ppm) at room temperature, and with an extreme bending radius of 3mm, it shows excellent mechanical reliability against repeated deformations over 1,000 bending cycles. The carbon fabric sensors are extremely flexible and durable even after bending, providing a stable resistance to the sensor base material. The results could be attractive to development of flexible, room temperature operable fabric based wearable gas sensing platforms.

Intrinsically disordered proteins (IDPs) not only play important roles in biological processes but are also linked with the pathogenesis of various human diseases. Specific and reliable sensing of IDPs is crucial for exploring their roles but remains elusive due to structural plasticity. Here, we present the development of a new type of fluorescent protein for the ratiometric sensing and tracking of an IDP. A β-strand of green fluorescent protein (GFP) was truncated, and the resulting GFP was further engineered to undergo the transition in the absorption maximum upon binding of a target motif within amyloid-β (Aβ) as a model IDP through rational design and directed evolution. Spectroscopic and structural analyses of the engineered truncated GFP demonstrated that a shift in the absorption maximum is driven by the change in the chromophore state from an anionic (460 nm) state into a neutral (390 nm) state as the Aβ binds, allowing a ratiometric detection of Aβ. The utility of the developed GFP was shown by the efficient and specific detection of an Aβ and the tracking of its conformational change and localization in astrocytes.

ABSTRACT This study evaluates the feasibility of using urea in cement composites, as a means to reduce the heat generated from the hydration of cement. The performed experimental evaluation uses [...]

During the reflow process in surface mount technology (SMT), a passive component misplaced on a pad would be self-aligned or tombstoned due to a restoring force which is driven by surface tension of molten solder. In this study, the influence of pad design on assembly defect rate was experimentally and analytically investigated using computational fluid dynamics (CFD) simulation. The assembly defect rate of the SMT was experimentally derived from the design of experiments (DOE) considering the pad design and the misplacement of the passive component. The restoring force and moment acting on the chip resistor were calculated using CFD simulation considering the fluidic forces of the molten lead-free solder paste during the reflow process according to the amount of the misplacement and the pad design parameters.

Because of the wide use of Fingolimod for the treatment of multiple sclerosis (MS) and its cardiovascular side effects such as bradycardia, second-generation sphingosine 1-phosphate receptor 1 (S1P1) agonist drugs for MS have been developed and approved by FDA. The issue of bradycardia is still present with the new drugs, however, which necessitates further exploration of S1P1 agonists with improved safety profiles for next-generation MS drugs. Herein, we report a tetrahydroisoquinoline or a benzo[c]azepine core-based S1P1 agonists such as 32and 60after systematic examination of hydrophilic groups and cores. We investigated the binding modes of our representative compounds and their molecular interactions with S1P1 employing recent S1P1 cryo-EM structures. Also, favorable ADME properties of our compounds were shown. Furthermore, in vivo efficacy of our compounds was clearly demonstrated with PLC and EAE studies. Also, the preliminary in vitro cardiovascular safety of our compound was verified with human iPSC-derived cardiomyocytes.

Printed Circuit Board (PCB) is a major component of the electronic device and it has been used in a diverse and extreme environment such as the data center near the coast. In this study, a simulation model was used to predict the corrosion lifetime of PCBs in marine atmospheric environments. The corrosion model was devised considering the dimensions of the PCB, biased voltage, and salt atmospheric environments. To prove the validity of the proposed model, a salt spray corrosion acceleration test was conducted. Finally, the corrosion life equations of the PCBs according to geometrical and environmental factors were proposed.

The most common type of dementia, Alzheimer's disease (AD), is marked by the formation of extracellular amyloid beta (Aβ) plaques. The impairments of axons and synapses appear in the process of Aβ plaques formation, and this damage could cause neurodegeneration. We previously reported that non-saponin fraction with rich polysaccharide (NFP) from Korean Red Ginseng (KRG) showed neuroprotective effects in AD. However, precise molecular mechanism of the therapeutic effects of NFP from KRG in AD still remains elusive.

Purpose: This research aims to analyze the customer satisfaction associated with experiences from 14 ecological hotels in Ecuador by exploring online guest reviews and classifying the most influential factors. Design/methodology/approach: This study applied big data exploration, semantic network analysis, EFA and linear regression. It processed 22,629 online reviews from Google/travel, extracting 100 words with the highest frequency. In addition, CONCOR analysis built a comprehensive structural model gathering essential keywords. Furthermore, exploratory factor analysis and regression were conducted to explore the elements that best express customer satisfaction in ecological hotels. Findings: The words such as green, sustainable, recycle, environment and ecological were not found among the main attributes extracted. Nonetheless, the keywords obtained reflect customer satisfaction, revealing that green practices do not affect comfort and the guests' experience. CONCOR analysis displayed four categories associated with satisfaction: tangibles, experience, location and empathy. Then, EFA restructured and revealed the factors: facilities feature, assurance, reliability, location and experience. Lastly, the regression disclosed location, assurance and facilities features as the most significant factors for customer satisfaction in the 14 ecological hotels. The terms related to the hotel area, staff care and hotel amenities were decisive for guests. Practical implications: This study demonstrated that employee courtesy and location are the keys to enhancing customer experience and satisfaction. Hotel managers must promote green attributes and practices to increase customer awareness through constant staff training and information disclosure in common areas. Originality/value: These findings provide insight and empirical evidence for hoteliers to understand how and what guest perceive to be green practices. By identifying the main features or concepts associated with satisfaction in Ecuador's green hotels, hoteliers could address new strategies to respond to expectations, effectively satisfy customers and provide a superior experience.

Recently, self-healing materials have evolved to recover specific functions such as electronic, magnetic, acoustic, structural or hierarchical, and biological properties. In particular, the development of self-healing protection coatings that can be applied to lens components in vision systems such as augmented reality glasses, actuators, and image and time-of-flight sensors has received intensive attention from the industry. In the present study, we designed polythiourethane dynamic networks containing a photothermal N-butyl-substituted diimmonium borate dye to demonstrate their potential applications in self-healing protection coatings for the optical components of vision systems. The optimized self-healing coating exhibited a high transmittance (∼95% in the visible-light region), tunable refractive index (up to 1.6), a moderate Abbe number (∼35), and high surface hardness (>200 MPa). When subjected to near-infrared (NIR) radiation (1064 nm), the surface temperature of the coating increased to 75 °C via the photothermal effect and self-healing of the scratched coatings occurred via a dynamic thiourethane exchange reaction. The coating was applied to a lens protector, and its self-healing performance was demonstrated. The light signal distorted by the scratched surface of the coating was perfectly restored after NIR-induced self-healing. The photoinduced self-healing process can also autonomously occur under sunlight with low energy consumption.

Carbon dots (CDs) are considered a potential substance for use in biomarker applications due to their exceptional light stability. However, there are several unsolved uncertainties about CD toxicity in vitro and in vivo. In this study, a redesigned derivative of the natural polysaccharide inulin is connected with boron-doped amine-functionalized carbon dots (In@BN-CDs) through carbodiimide coupling to improve the biocompatibility of the nanoformulation. The toxicity and biodistribution of ln@BN-CDs in vivo and in vitro were explored in detail. The In@BN-CDs were tested after a single inhalation dosage of 10, 7, 5, 3, and 1 mg/kg. We explored a dose- and time-dependent technique of collecting blood samples and then centrifuged the blood samples and obtained serum samples, which were then analyzed for fluorescence inspection; findings showed that the fluorescence intensity decreased with time. Similarly, In@BN-CDs were effectively used as in vitro toxicity and fluorescent probes for cellular imaging in living cells due to their biocompatibility and cell membrane accessibility. The biocompatibility and efficacy of In@BN-CDs as fluorescent imaging agents have been demonstrated. The data suggest that the usage of In@BN-CDs in vitro and in vivo should be examined.

In the anatomy of human eye, the role of iris is crucial since it controls the light level entering the eye and enhances the visibility. Here, we propose a soft contact lens type artificial iris actuated by eternal UV (ultra‐violet) light source, self‐regulating its effective aperture size by varying the crosslinking density of bio‐compatible polymer matrix doped with photochromic dye. For its self‐regulating characteristic, we cured HEMA‐based polymer matrix gradually from center to edge. Since the polymer matrix is polymerized by heat, we utilized NIR (near infra‐red) lamp and gradient grayscale patterned photomask for its gradual characteristic. Thereby, the crosslinking density of central position is higher compared to that of peripheral, causing slow switching dynamics. The gradient difference in switching dynamics leads to artificial iris gaining self‐regulation dynamics of effective aperture. The manufactured artificial iris shows advantage in blocking UV light, self‐regulating, and fast switching dynamics. The switching dynamics of artificial iris under bright and dim light adaptation are less than 50 seconds and 120 seconds, showing similar property with human iris.

Owing to the rise in global population and living standards, waste treatment has inevitably become a critical issue for a sustainable environment. In particular, for an effective recycling process, it is vital to disassemble different types of materials by removing adhesives used in the packaging. However, this removal process requires harsh solvents (acidic and organic) that are unfriendly to nature and may cause additional pollution. To address this issue, functional adhesive materials that can be removed without the use of harsh solvents have drawn significant attention. One promising approach is to utilize the stimuli-responsive polymers to synthesize pressure sensitive adhesives (PSAs); however, it is technically challenging to simultaneously satisfy (i) strong initial adhesion (without stimulus), (ii) stimuli-responsive sufficient reduction of adhesion, and (iii) reversibility. In this study, thermo-switchable PSAs were synthesized by copolymerizing N-isopropylacrylamide (NIPAM), which possesses thermal-responsive properties; acrylic acid, which endows adhesive properties; and 2-ethylhexyl acrylate, which has a low glass transition temperature to attain sufficient flexibility. The synthesized NIPAM-based thermo-switchable PSAs exhibited significantly high peel strength at room temperature (∼15.41 N/25 mm at 20 °C), which decreased by ∼97% upon heating (∼0.46 N/25 mm at 80 °C). Importantly, no residues remained due to the cohesive nature of NIPAM at high temperature. The reversible adhesion behaviour of the thermo-switchable PSAs was retained during repeated heating and cooling cycles. Therefore, the developed thermo-switchable PSA can enhance the reusability and recyclability of valuable materials and minimize the use of toxic chemicals for adhesive removal, contributing to a more sustainable future.

In this study, the gas absorption and particle removal performance of wet parallel-membrane array systems were investigated. SO2 and oil mist were used as the target gas and particles, respectively. To evaluate the gas absorption performance of the wet membrane, we compared it with a packed-bed scrubber at the same flow rate. Unlike a typical packed-bed scrubber, the membrane scrubber has a high absorption rate and easily absorbs water so that the liquid flows dynamically across the entire membrane. Therefore, the membrane exhibited a higher mass transfer rate than the packed bed. In addition, the pressure drop was extremely low because the flow was not blocked. We evaluated the particle removal performance of a wet two-stage electrostatic precipitator (ESP) with a wet parallel-membrane array collection stage. A PM2.5 removal efficiency higher than 90% at a flow velocity of 1 m/s was achieved using the proposed system. In addition, the wet-membrane-based two-stage ESP was easy to design according to the existing ESP design theory, Cochet's charging theory, and Deutsch equation. Also, our new wet-membrane-based two-stage ESP can remove acid gas and particles simultaneously. Therefore, this membrane can be a promising material for air pollution control devices, such as scrubbers and ESPs.

This research used an electrostatic precipitator (ESP) with multiple sawtooth discharge electrode plates and one hollow cylindrical collecting electrode. The discharge electrode was a circular plate with sawtooth spikes. The collection efficiency was analyzed via simulations using three geometric parameters: the outermost diameter of the discharge electrode, the distance between the electrode plates, and the number of spikes. Among the cases considered for the discharge electrode geometry optimization using the Taguchi method, the parameter combination with the highest collection efficiency was selected. The simulation result was verified by building electrostatic precipitator geometry before and after its optimization and subsequently measuring its collection efficiencies. The collection efficiency of an ESP with the discharge electrode of the optimal geometry was higher by 15% than that of its reference geometry. It is expected that the collection efficiency of other types of ESP can be maximized using a similar discharge electrode geometry optimization.

Microorganisms on the surface are important contributors to producing a serious threat to global public health. Herein, we introduce an electro-thermal antimicrobial carbon surface. When a 9 V direct voltage was applied to the carbon surface, the carbon fibre surface temperature reached 80 °C. This electro-thermal-based antimicrobial carbon surface showed outstanding inactivation performance, exhibiting a potent inactivation rate of ∼99.99% against Gram-positive bacteria (Staphylococcus epidermidis) and Gram-negative bacteria (Escherichia coli) in just 10 min. Interestingly, under the same temperature, when alternating voltages were applied, electro-thermal antimicrobial performance was enhanced, resulting in a >6.0 log reduction against both Gram-positive and Gram-negative bacteria. In addition, under alternating voltage applied conditions, this excellent electro-thermal-based antimicrobial performance was maintained even at a lower surface temperature (50 °C).

In this study, we investigated the particulate matter (PM) removal efficiency and durability of the two-stage electrostatic precipitator (ESP) different materials of brush-typed ionizers (non-metal: carbon fiber/metal: stainless steel (SUS) fiber). The PM removal efficiency was reduced when the average diameter and number of fibers of the brush-typed ionizer increased due to thin and multi-edge in a large number of fibers, which decreased the average electric field, resulting in lower PM removal efficiencies. In contrast with the carbon fiber ionizer, when the SUS fiber ionizer was used, the PM removal efficiency was maintained for a long time, due to its lower electrical resistivity (∼6.9 × 10−7 Ω * m) of the SUS fiber compared with the carbon fiber (∼5 × 10−4 Ω * m), which prevents the positive ions to be stacked on the fiber. Therefore, the present research showed the potential use to apply SUS fiber ionizers as two-stage ESPs for a future air pollution control technology with high PM removal efficiency and durability without ozone emission and additional maintenance.

Purpose: A properly ion-balanced nutrient solution is vital for plant growth. However, when reusing a nutrient solution, the nutrient balance is likely to fluctuate and become unsuitable for irrigation. Ionic imbalance problems that cause plant growth disorders in nutrient solutions can be minimized if the nutrient concentration of the various water sources can be determined and considered when making the nutrient solution. In this study, a closed hydroponic nutrient management algorithm for multiple water sources was developed. Methods: The concentrations of NO3−, K+, and Ca2+ions in the nutrient solution and various water sources were measured in real time and calculated to automatically replenish insufficient ions. For this purpose, ion-selective electrodes (ISEs) were selected for the determination of NO3−, K+, and Ca2+ion concentrations and eight stock solutions for individual salt replenishment. Results: Performance tests were conducted to verify the developed system’s ability to maintain NO3−, K+, and Ca2+ion concentrations at their target values. The nutrient solution dosing accuracy obtained in the stepwise management test was evaluated using root mean square error (RMSE). In addition, long-term performance evaluation of the developed algorithm was validated while growing lettuce using the closed nutrient film technique (NFT). The long-term accuracy of the developed system was RMSE 60.6, 21.0, and 9.86 mg/L for the NO3−, K+, and Ca2+ions, respectively. Conclusion: The results of this study showed nutrient management using multiple water sources by applying three different ISE sensors, NO3−, K+, and Ca2+. With the further development of ISE technology, it would be possible to control all six macronutrients in the nutrient solution.

Study Design: Prospective observational study.Objective: In ACDF, graft failure and subsidence are common complications of surgery. Depending on the cervical fixation, different biomechanical characteristics are applied on the grafts. This aims to describe the incidence of cervical spacer failure in patients with cervical degenerative condition according to the cervical fixation method and sagittal balance.Method: From November 2011 to December 2015, 262 patients who underwent cervical spine surgery were enrolled prospectively. Patients were divided into 3 groups based on fixation method: anterior plate/screw (APS), posterior lateral mass screw (LMS), pedicle screw (PPS) groups. Serial X-rays and CT scans were utilized to evaluate radiologic outcomes.Results: Mean patient ages were 56.1 years in the APS group, 61.5 years in the LMS group, and 57.6 years in the PPS group (P= 0.002). Allospacer failure was most common in the APS group, compared to the LMS and PPS groups (chi-square, P= 0.038). Longer fusion level was associated with greater allospacer failure (Baseline 2 level surgery; Odds ratio (OR) 3.4 in 3 level, 15.2 in 4 level, P= 0.036,0.013). Higher T1 slope was correlated with less allospacer failure (OR 0.875, P= 0.001). ORs of allospacer failure in the LMS and PPS groups were 0.04 and 0.02, respectively, (P= 0.01, 0.01), compared with the APS group.Conclusion: This study was able to show that allospacer failure in multi-level ACDF surgery is more common with a longer fusion length, less postoperative T1 slope, and an anterior plate-screws technique. Pedicle screws provided the best biomechanical stability among the 3 constructs.

To assess temporal improvement of prostate image reporting and data system (PIRADS) 3-5 lesion correlation to histopathologic findings from radical prostatectomy (RP) in prostate cancer (PCa).