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Due to its outstanding physical and chemical properties, graphene synthesized by laser scribing on polyimide (PI) offers excellent opportunities for photothermal applications, antiviral and antibacterial surfaces, and electrochemical storage and sensing. However, the utilization of such graphene for imaging is yet to be explored. Herein, using chemically durable and electrically conductive laser-induced graphene (LIG) for tomography imaging in aqueous suspensions is proposed. These graphene electrodes are designed as impedance imaging units for four-terminal electrical measurements. Using the real-time portable imaging prototypes, the conductive and dielectric objects can be seen in clear and muddy water with equivalent impedance modeling. This low-cost graphene tomography measurement system offers significant advantages over traditional visual cameras, in which the suspended muddy particles hinder the imaging resolution. This research shows the potential of applying graphene nanomaterials in emerging marine technologies, such as underwater robotics and automatic fisheries.
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This study explores the psychological motivations that drive ChatGPT users to embrace and sustain the use of such technology based on the fundamental notion of the environmental psychology theory, including servicescapes. To do so, this study delves into the influence of ChatGPT's e-servicescapes on users' emotional states and intention to engage with ChatGPT for decision-making processes. This study conducted an online survey among ChatGPT users in the United States. Structural equation modeling revealed that negative emotions were significantly influenced by various e-servicescape sub-dimensions, including security, visual appeal, entertainment value, originality of design, and social factors. Positive emotions, on the other hand, were influenced by factors such as visual appeal, customization, interactivity, and relevance of information. Both positive and negative emotions significantly affected user satisfaction, which, in turn, shaped their behavioral intention to engage with ChatGPT. This study contributes to the understanding of digital environmental psychology and chatbots by extending the notion of e-servicescapes to the context of AI-based services. It underscores the significance of e-servicescapes in shaping user experiences and provides valuable insights for business scholars and marketing practitioners.
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Extracellular vesicles, particularly exosomes, have emerged as promising drug delivery systems owing to their unique advantages, such as biocompatibility, immune tolerability, and target specificity. Various engineering strategies have been implemented to harness these innate qualities, with a focus on enhancing the pharmacokinetic and pharmacodynamic properties of exosomes via payload loading and surface engineering for active targeting. This concise review outlines the challenges in the development of exosomes as drug carriers and offers insights into strategies for their effective clinical translation. We also highlight preclinical studies that have successfully employed anti-inflammatory exosomes and suggest future directions for exosome therapeutics. These advancements underscore the potential for integrating exosome-based therapies into clinical practice, heralding promise for future medical interventions.
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Sistemas de Liberación de Medicamentos , Exosomas , Exosomas/metabolismo , Humanos , Sistemas de Liberación de Medicamentos/métodos , Animales , Portadores de Fármacos/químicaRESUMEN
A novel Gram-stain-negative, yellow-pigmented, short rod-shaped bacterial strain, HBC34T, was isolated from a freshwater sample collected from Daechung Reservoir, Republic of Korea. The results of 16S rRNA gene sequence analysis indicated that HBC34T was affiliated with the genus Sphingobium and shared the highest sequence similarity to the type strains of Sphingobium vermicomposti (98.01â%), Sphingobium psychrophilum (97.87â%) and Sphingobium rhizovicinum (97.59â%). The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between HBC34T and species of the genus Sphingobium with validly published names were below 84.01 and 28.1â%, respectively. These values were lower than the accepted species-delineation thresholds, supporting its recognition as representing a novel species of the genus Sphingobium. The major fatty acids (>10â% of the total fatty acids) were identified as summed feature 8 (C18â:â1ω7c and/or C18â:â1ω6c) and summed feature 3 (C16â:â1ω7c and/or C16â:â1ω6c). The main polar lipids were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, two phospholipids and two unidentified polar lipids. The respiratory quinone was Q-10. The genomic DNA G+C content of HBC34T was 64.04â%. The polyphasic evidence supports the classification of HBC34T as the type strain of a novel species of the genus Sphingobium, for which the name Sphingobium cyanobacteriorum sp. nov is proposed. The type strain is HBC34T (= KCTC 8002T= LMG 33140T).
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Ácidos Grasos , Agua Dulce , Composición de Base , Ácidos Grasos/química , ARN Ribosómico 16S/genética , Filogenia , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación BacterianaRESUMEN
Self-cleaning and anti-biofouling are both advantages for lotus-leaf-like superhydrophobic surfaces. Methods for creating superhydrophobicity, including chemical bonding low surface energy molecular fragments and constructing surface morphology with protrusions, micropores, and trapped micro airbags by traditional physical strategies, unfortunately, have encountered challenges. They often involve complex synthesis processes, stubborn chemical accumulation, brutal degradation, or infeasible calculation and imprecise modulation in fabricating hierarchical surface roughness. Here, a scalable method to prepare high-quality, breathable superhydrophobic membranes is proposed by developing a successive roll-to-roll laser manufacturing technique, which offers advantages over conventional fabrication approaches in enabling automatically large-scale production and ensuring cost-effectiveness. Nanosecond laser writing and femtosecond laser drilling produce surface microstructures and micropore arrays, respectively, endowing the membrane with superior antiwater capability with hierarchical microstructures forming a barrier and blocking water infiltration. The membrane's breathability is carefully optimized by tailoring micropore arrays to allow for the adequate passage of water vapor while maintaining superhydrophobicity. These membranes combine the benefits of anti-aqueous corrosive liquid behaviors, photothermal effects, thermoplastic properties, and stretchable performances as promising comprehensive materials in diverse scenes.
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The purpose of this study is to evaluate the derived concentration guideline levels for unrestricted site reuse the Korea research reactor unit 1 and 2. Distribution coefficients for Co-60 and Sr-90 were derived, and site-specific values of the KRR soil were applied for the DCGLs for the seven target nuclide. The distribution coefficients of Co-60 and Sr-90 were 6,128 and 86.0 mL/g. The DCGLs derived from the dose by age group were 0.053 Bq/g for Co-60 and 45.0 Bq/g for H-3.
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BACKGROUND: Collagen is a key component of connective tissue and has been frequently used in the fabrication of medical devices for tissue regeneration. Human-originated collagen is particularly appealing due to its low immune response as an allograft biomaterial compared to xenografts and its ability to accelerate the regeneration process. Ethically and economically, adipose tissues available from liposuction clinics are a good resource to obtain human collagen. However, studies are still scarce on the extraction and characterization of human collagen, which originates from adipose tissue. The aim of this study is to establish a novel and simple method to extract collagen from human adipose tissue, characterize the collagen, and compare it with commercial-grade porcine collagen for tissue engineering applications. METHODS: We developed a method to extract the collagen from human adipose tissue under quasi-Good Manufacturing Practice (GMP) conditions, including freezing the tissue, blood removal, and ethanol-based purification. Various techniques, including protein quantification, decellularization assessment, SDS-PAGE, FTIR, and CD spectroscopy analysis, were used for characterization. Amino acid composition was compared with commercial collagen. Biocompatibility and cell proliferation tests were performed, and in vitro tests using collagen sponge scaffolds were conducted with statistical analysis. RESULTS: Our results showed that this human adipose-derived collagen was equivalent in quality to commercially available porcine collagen. In vitro testing demonstrated high cell attachment and the promotion of cell proliferation. CONCLUSION: In conclusion, we developed a simple and novel method to extract and characterize collagen and extracellular matrix from human adipose tissue, offering a potential alternative to animal-derived collagen for xeno-free tissue engineering applications.
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Ingeniería de Tejidos , Andamios del Tejido , Porcinos , Animales , Humanos , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Tejido Adiposo/metabolismo , Colágeno/química , Matriz ExtracelularRESUMEN
Glioblastoma (GBM) is the deadliest tumor of the central nervous system, with a median survival of less than 15 months. Despite many trials, immune checkpoint-blocking (ICB) therapies using monoclonal antibodies against the PD-1/PD-L1 axis have demonstrated only limited benefits for GBM patients. Currently, the main hurdles in brain tumor therapy include limited drug delivery across the blood-brain barrier (BBB) and the profoundly immune-suppressive microenvironment of GBM. Thus, there is an urgent need for new therapeutics that can cross the BBB and target brain tumors to modulate the immune microenvironment. To this end, we developed an ICB strategy based on the BBB-permeable, 24-subunit human ferritin heavy chain, modifying the ferritin surface with 24 copies of PD-L1-blocking peptides to create ferritin-based ICB nanocages. The PD-L1pep ferritin nanocages first demonstrated their tumor-targeting and antitumor activities in an allograft colon cancer model. Next, we found that these PD-L1pep ferritin nanocages efficiently penetrated the BBB and targeted brain tumors through specific interactions with PD-L1, significantly inhibiting tumor growth in an orthotopic intracranial tumor model. The addition of PD-L1pep ferritin nanocages to triple in vitro cocultures of T cells, GBM cells, and glial cells significantly inhibited PD-1/PD-L1 interactions and restored T-cell activity. Collectively, these findings indicate that ferritin nanocages displaying PD-L1-blocking peptides can overcome the primary hurdle of brain tumor therapy and are, therefore, promising candidates for treating GBM.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Antígeno B7-H1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Ferritinas/uso terapéutico , Péptidos/uso terapéutico , Microambiente TumoralRESUMEN
Sulfide-based electrolytes, with their high conductivity and formability, enable the construction of high-performance, all-solid-state batteries (ASSBs). However, the instability of the cathode-sulfide electrolyte interface limits the commercialization of these ASSBs. Surface modification of cathodes using the coating technique has been explored as an efficient approach to stabilize these interfaces. In this study, the additives lithium difluorophosphate (LiDFP) and lithium difluoro(oxalato)borate (LiDFOB) are used to fabricate stable cathode coatings via heat treatment. The low melting points of LiDFP and LiDFOB enable the formation of thin and uniform coating layers by a low-temperature heat treatment. All-solid-state cells containing LiDFP- and LiDFOB-coated cathodes show electrochemical performances significantly better than those comprising uncoated cathodes. Among all of the as-prepared coated cathodes, LiDFP-coated cathodes fabricated using a slightly lower temperature than the phase-transition temperature of LiDFP (320 °C) show the best discharge capacity, rate capability, and cyclic performance. Furthermore, cells comprising LiDFP-coated cathodes showed significantly low impedance. X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy confirm the effectiveness of the LiDFP coating. LiDFP-coated cathodes minimized side-reactions during cycling, resulting in a significantly low cathode-surface degradation. Hence, this study highlights the efficiency of the proposed coating method and its potential to facilitate the commercialization of ASSBs. Overall, this study reports an effective technique to stabilize the cathode-electrolyte interface in sulfide-based ASSBs, which could expedite the practical implementation of these advanced energy-storage devices.
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This study investigates the use of live streaming as a strategic tool in the tourism industry, with a focus on the attributes of live streamers that influence viewer engagement, particularly in the context of South Korea's digital landscape. The purpose of this research is to understand how the attractiveness, trustworthiness, and expertise of live streamers can affect the parasocial relationships-characterized by perceived friendship and trust-between viewers and streamers and how these relationships subsequently influence viewer loyalty and cooperation intentions. A quantitative research methodology was employed, utilizing a structured online survey distributed by a leading market research agency in South Korea. The survey targeted a diverse demographic to ensure a comprehensive analysis of digital consumer behavior in the tourism sector. Data were analyzed using IBM SPSS Statistics 28.0 and IBM SPSS Amos 28.0, employing structural equation modeling to test the hypothesized relationships. The results revealed that while attractiveness and trustworthiness impact perceived friendship, only expertise significantly affects trust for a travel live streamer. Furthermore, perceived friendship plays a crucial role in fostering loyalty to and cooperation with the streamer, having practical implications for the tourism industry in terms of crafting marketing strategies and training digital ambassadors. Th study extends parasocial interaction theory to the digital travel domain, providing original insights into virtual tourist behavior and highlighting live streaming's significant contribution to viewer engagement. This research has limitations in its geographical focus on South Korea, suggesting the need for cross-cultural studies to validate the findings. Overall, this study offers valuable contributions to the academic literature and practical guidance for the tourism industry, emphasizing the importance of digital personalities in post-pandemic tourism recovery strategies.
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The coronavirus disease 2019 pandemic persisted for 3 years and is now transitioning to endemicity. We illustrated the change in group immunity induced by vaccination (monovalent vaccines) and breakthrough infections (BIs) in a healthcare worker (HCW) cohort. Five sampling points were analyzed: before the third dose and 1, 3, 5, and 8 months after the vaccination. The last two points corresponded roughly to 1 and 4 months after omicron BA.1/BA.2 BI. A semi-quantitative anti-spike binding antibody (Sab) assay and plaque reduction neutralization test (PRNT) against circulating variants were conducted. A linear regression model was utilized to deduce correlation equations. Baseline characteristics and antibody titers after the third dose were not different between 106 HCWs with or without BI (54/52). One month after the third dose, BA.1 PRNT increased with wild-type (WT), but 3 months after the third dose, it decreased more rapidly than WT PRNT. After BI, BA.1 PRNT increased robustly and waned slower than WT. A linear equation of waning kinetics was deduced between log10Sab and months, and the slope became gradual after BI. The estimated BA.5 PRNT titers at the beginning of the BA.5 outbreak were significantly higher than the BA.1 PRNT titers of the initial BA.1/BA.2 wave, which might be associated with the smaller size of the BA.5 wave. BA.1/BA.2 BI after the third dose elicited robust and broad neutralizing activity, preferentially maintaining cross-neutralizing longevity against BA.1 and BA.5. The estimated kinetics provide an overview of group immunity through the third vaccination and BA.1/BA.2 BI, correlating with the actual outbreaks. IMPORTANCE This study analyzed changes in group immunity induced by coronavirus disease 2019 (COVID-19) vaccination and BA.1/BA.2 breakthrough infections (BIs) in a healthcare worker cohort. We investigated the longitudinal kinetics of neutralizing antibodies against circulating variants and confirmed that BA.1/BA.2 BIs enhance the magnitude and durability of cross-neutralization against BA.1 and BA.5. Correlation equations between semi-quantitative anti-spike antibody and plaque reduction neutralization test titers were deduced from the measured values using a linear regression model. Based on the equations, group immunity was estimated to last up to 11 months following the third dose of the COVID-19 vaccine. The estimated group immunity suggests that the augmented immunity and flattened waning slope through BI could correlate with the overall outbreak size. Our findings could provide a better understanding to establish public health strategies against future endemicity.
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This research investigates the factors influencing user satisfaction and dissatisfaction in fitness mobile applications. It employs Herzberg's two-factor model through text mining to classify Fitbit mobile app attributes into satisfiers and dissatisfiers. The Fitbit app was chosen due to its prevalence in the United States. The study analyzes 100,000 English reviews from the Fitbit app on the Google Play Store, categorizing attributes. It identifies three dissatisfying categories (functional, compatibility, paid services) and three satisfying categories (gratification, self-monitoring, self-regulation), comprising 25 sub-attributes. This classification offers in-depth insights into what drives user contentment or discontent with fitness apps. The findings contribute to the fitness app domain by applying text-mining and Herzberg's model. Researchers can build upon this foundation, and practitioners can use it to enhance app experiences. However, this research relies on user reviews, often lacking comprehensive explanations. This limitation may hinder a profound understanding of the underlying psychological aspects in user sentiments. Nonetheless, this study takes strides toward optimizing fitness apps for users and developers.
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As one of the most widely used commodity plastics, poly(vinyl chloride) (PVC) is extensively used worldwide, yet is difficult to recycle and is often discarded immediately after use. Its end-of-life treatment often generates toxic hydrogen chloride and dioxins that pose a critical threat to ecosystems. To address this challenge, the mechanochemical degradation of PVC into water-soluble biocompatible products is presented herein. Oxirane mechanophores are strategically introduced into the polymeric backbone via sequential dechlorination followed by epoxidation. The oxirane mechanophore in the polymer backbone undergoes a force-induced heterolytic ring-opening to carbonyl ylide intermediates, which eventually generates acetals during the course of the reaction. The subsequent hydrolysis of the backbone acetals affords the scission of the polymeric chain into water-soluble low-molecular-weight fragments. Combined with its low cytotoxicity and phytotoxicity, this solvent-free mechanochemical degradation process offers a green alternative for the degradation of PVC.
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Patterning is crucial for the large-scale application of functional materials. Laser-induced transfer is an emerging patterning method for additively depositing functional materials to the target acceptor. With the rapid development of laser technologies, this laser printing method emerges as a versatile method to deposit functional materials in either liquid or solid format. The emerging applications such as solar interfacial evaporation, solar cells, light-emitting diodes, sensors, high-output synthesis, and other fields are rising fields benefiting from laser-induced transfer. Following a brief introduction to the principles of laser-induced transfer, this review will comprehensively deliberate this novel additive manufacturing method, including preparing the donor layer and the applications, advantages, and limitations of this technique. Finally, perspectives for handling current and future functional materials using laser-induced transfer will also be discussed. Non-experts in laser technologies can also gain insights into this prevailing laser-induced transfer process, which may inspire their future research.
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Rayos Láser , Programas InformáticosRESUMEN
BACKGROUND: The repressor element-1 silencing transcription factor (REST), a master transcriptional repressor, is essential for maintenance, self-renewal, and differentiation in neuroblastoma. An elevated expression of REST is associated with impaired neuronal differentiation, which results in aggressive neuroblastoma formation. E3 ligases are known to regulate REST protein abundance through the 26 S proteasomal degradation pathway in neuroblastoma. However, deubiquitinating enzymes (DUBs), which counteract the function of E3 ligase-mediated REST protein degradation and their impact on neuroblastoma tumorigenesis have remained unexplored. METHODS: We employed a CRISPR/Cas9 system to perform a genome-wide knockout of ubiquitin-specific proteases (USPs) and used western blot analysis to screen for DUBs that regulate REST protein abundance. The interaction between USP3 and REST was confirmed by immunoprecipitation and Duolink in situ proximity assays. The deubiquitinating effect of USP3 on REST protein degradation, half-life, and neuronal differentiation was validated by immunoprecipitation, in vitro deubiquitination, protein-turnover, and immunostaining assays. The correlation between USP3 and REST expression was assessed using patient neuroblastoma datasets. The USP3 gene knockout in neuroblastoma cells was performed using CRISPR/Cas9, and the clinical relevance of USP3 regulating REST-mediated neuroblastoma tumorigenesis was confirmed by in vitro and in vivo oncogenic experiments. RESULTS: We identified a deubiquitinase USP3 that interacts with, stabilizes, and increases the half-life of REST protein by counteracting its ubiquitination in neuroblastoma. An in silico analysis showed a correlation between USP3 and REST in multiple neuroblastoma cell lines and identified USP3 as a prognostic marker for overall survival in neuroblastoma patients. Silencing of USP3 led to a decreased self-renewal capacity and promoted retinoic acid-induced differentiation in neuroblastoma. A loss of USP3 led to attenuation of REST-mediated neuroblastoma tumorigenesis in a mouse xenograft model. CONCLUSION: The findings of this study indicate that USP3 is a critical factor that blocks neuronal differentiation, which can lead to neuroblastoma. We envision that targeting USP3 in neuroblastoma tumors might provide an effective therapeutic differentiation strategy for improved survival rates of neuroblastoma patients.
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Neuroblastoma , Factores de Transcripción , Animales , Humanos , Ratones , Diferenciación Celular/genética , Transformación Celular Neoplásica/genética , Sistemas CRISPR-Cas , Neuroblastoma/genética , Neuronas/fisiología , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , UbiquitinaciónRESUMEN
Mechanically soft metallic nanocomposites have gained much attention as a key material for intrinsically stretchable biointegrated devices. However, it has been challenging to develop a stretchable conductive nanocomposite with all the desired material characteristics including high conductivity, high stretchability, low cytotoxicity, and low impedance. Here, we present a material strategy for the stretchable conductive nanocomposite, particularly emphasizing low impedance, by combining silver-gold-platinum core-shell-shell nanowires and homogeneously dispersed in situ synthesized platinum nanoparticles (Pt NPs). The highly embossed structure of the outermost Pt shell, together with the intrinsic electrical property of Pt, contributes to minimizing the impedance. The gold-platinum double-layer sheath prevents leaching of cytotoxic Ag ions, thus improving biocompatibility. Homogeneously dispersed Pt NPs, synthesized in situ during fabrication of the nanocomposite, simultaneously enhance conductivity, reduce impedance, and improve stretchability by supporting the percolation network formation. This intrinsically stretchable nanocomposite conductor can be applied to wearable and implantable bioelectronics for recording biosignals and delivering electrical stimulations in vivo.
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Nanopartículas del Metal , Nanocables , Dispositivos Electrónicos Vestibles , Nanocables/química , Impedancia Eléctrica , Nanopartículas del Metal/química , Platino (Metal) , Oro/químicaRESUMEN
Ring-opening alternating copolymerization (ROAC) of cyclic anhydrides and epoxides has emerged as a powerful strategy to produce degradable polyesters with a diverse array of structures from the combination of two distinct building blocks. In this work, we exploited the organocatalytic ROAC of cyclic anhydrides and a functional epoxide, t-butyl glycidoxy acetate, followed by acidic deprotection to access degradable polyesters with carboxylic acid pendants. To study the interplay between monomers, diglycolic anhydride and glutaric anhydride were used as cyclic anhydrides to prepare two polyesters. In particular, the effects of the oxygen heteroatom in the cyclic anhydrides on the properties of the carboxylic acid-containing polyesters were investigated. The introduction of the oxygen heteroatom into the cyclic anhydrides significantly influenced their thermal properties and pH-dependent self-association behavior in an aqueous solution. Furthermore, molecular dynamics simulations elucidate that the number and type of hydrogen bonds play a crucial role in the self-association behavior between the polymers both in the solution and bulk states. The findings of this study highlight the importance of the interplay between monomers in the design of functional polyesters with tunable properties.
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This study emphasized the source credibility effect on consumers' responses to restaurant companies' CSR efforts on social media. Based on the source credibility brand development process (i.e., brand trust, brand affect, and brand engagement), this study employed an online survey-based experiment and revealed the meaningful associations among types of CSR posters (a restaurant brand vs. a nonprofit organization), brand trust, brand affect, and brand engagement. The empirical results indicated that the nonprofit organization has higher significant effects on brand trust and brand affect than those of the restaurant brand. Additionally, in the case of the nonprofit organization, the effects of brand trust and brand affect on brand engagement were significantly stronger than that of the restaurant brand. Based on the empirical findings, this study provided several theoretical and managerial implications for restaurant companies' CSR communication on social media.
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The purpose of this study is to apply a probabilistic method to derive the derived concentration guideline levels for decommissioning of Korea Research Reactor 1 and 2. A total of seven parameters were found to be the sensitive parameters of the target nuclides. The DCGLs of Co-60 and H-3 were 0.063 Bq/g and 85.470 Bq/g, respectively. The concentrations of the gamma ray-emitting nuclides in the actual reactor sites were 7.7-215 times lower than the derived DCGLs for gamma ray-emitting nuclides.
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In this study, using the Protection Motivation Theory (PMT), we examine whether protection motivation can explain restaurant patron intention to practice self-protection. New normal practices are in place in the restaurant industry that influence dining out behavior during the COVID-19 pandemic. Based on 402 usable questionnaires collected face to face with residents in Phuket, Thailand, and using structural equation modeling to analyze the data, we found self-protective intention is influenced more by the perceived threat of COVID-19, but the actual behavior of visit frequency and protective behavior is influenced more by the positive PMT factors: perceived efficacy or self-confidence about protecting oneself and the expected rewards of dining out. In addition, the study highlights the important role of self-protective intention as a mediator in the relationships between PMT factors and actual behaviors of restaurant clients, especially their protection behaviors. Academic and practical implications are discussed.