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One-pot synthesis of gold nanoparticles coated with electron beam-irradiated hyaluronic acid was developed to achieve a pH-dependent sulfasalazine release system with high drug encapsulation efficiency.

The emergency conservation of historical objects is necessary because several instances in which paintings and records were flooded owing to unusual weather conditions have recently been reported. Early action is especially important in preventing biodeterioration in case of flood damage. In this study, the feasibility of using gamma rays as a biological control method was assessed. Material stability was evaluated by applying different irradiation doses to natural dyes used in historical paintings and costumes. Sappan wood, gardenia fruit, and indigo were selected and prepared as natural dye samples using standard colorant materials. The fading behavior of the samples was analyzed by measuring their CIE L*a*b* color space values, and UV-Vis spectroscopy and liquid chromatography tandem mass spectrometry (LC-MS) were used to obtain their spectra. We confirmed that the dyes began to decompose upon exposure to gamma rays at a dose of 10 kGy. Irradiation at a dose of 50 kGy led to the complete decomposition of the chromophoric groups because the dye components could not be detected by LC-MS. Therefore, studying the influence of low-dose gamma-ray irradiation is necessary to preserve dye colorants. The data obtained in this study can be used as a foundation for further research on the influence of gamma rays on historical objects.

Purpose: Triage tools play a vital role in classifying the severity of children in emergency departments (EDs). We investigated the association between the Korean Triage and Acuity Scale (KTAS) and severity of dyspnea in the ED.Methods: We conducted a retrospective study of children aged 3-14 years with dyspnea who visited the ED from January 2015 through December 2021. They were divided into severe (KTAS level 1-3) and non-severe (KTAS level 4-5) groups. Between the groups, we compared the clinical characteristics, including age, sex, associated symptoms, vital signs, route of visit, treatment at ED, and outcomes. Results: Among a total of 468 children with dyspnea, 267 and 201 were assigned to the severe and non-severe groups, respectively. The severe group had higher frequencies of fever (21.7% vs. 13.9%; P = 0.031), cough (53.2% vs. 43.3%; P = 0.034), systemic steroids (42.3% vs. 25.9%; P < 0.001), intravenous fluids (47.6% vs. 25.4%; P < 0.001), oxygen therapy (16.5% vs. 6.5%; P = 0.001), inotropics (4.1% vs. 1.0%; P = 0.042), and hospitalization (24.7% vs. 11.9%; P = 0.002). The severe group also showed a higher mean heart rate, respiratory rate, and temperature, and lower mean oxygen saturation (all Ps < 0.001). Among these findings, fever, heart rate, respiratory rate, temperature, intravenous fluids, oxygen therapy, inotropics, and hospitalization remained significantly different between the groups after defining the severe group as a KTAS level 1-2.Conclusion: This study shows the association between KTAS and severity of dyspnea in the ED. Therefore, KTAS may reflect not only the initial clinical conditions but also emergency measures and outcomes in children with dyspnea who visit EDs.

Purpose: Using simulation in continuing professional development (CPD) courses for local practitioners is uncommon in Korea. The aim of our study was to evaluate the responses of the local practitioners for a simulation-based short CPD course.Methods: Following the targeted needs assessment of local practitioners, we developed and implemented a 3-hour simulation-based CPD course for the first 5 minutes of cardiac arrest in the resource-limited local clinics. We evaluated the participant’s responses to the course using a questionnaire.Results: During the 3-year implementation period, 115 practitioners participated in 10 courses, and 113 (98%) responded to the questionnaire. The overall course satisfaction (10-point scale) was very positive (10 in 93 [82.3%], 9 in 19 [16.8%], and 8 in 1 [0.8%]). The level (5-point scale) of recommendation to the others was also high (5 in 103 [91.2%] and 4 in 10 [8.8%]). Many participants positively commented on the authentic practical experience of the uncommon crisis in their contexts.Conclusion: A simulation-based short CPD course for in-hospital cardiac arrest could provide an authentic practical experience for local practitioners working in resource-limited clinics.

Objectives: Tai Chi, an ancient Chinese martial art, has been credited for improving the physical and mental health of community-dwelling older adults. Virtual reality (VR) has developed as a therapeutic technique for improving health and well-being in older adults. Previous research on exercise-based VR interventions in older adults has focused primarily on the physical and cognitive health effects. The extent to which a program integrating the ancient practice of Tai Chi with virtual reality might benefit older individuals' physical and mental health is an unknown entity. In this pilot study, we examined potential advantages of the virtual Tai Chi program in terms of health outcomes, as well as to gather qualitative data on the barriers to VR program participation. Methods: We conducted semi-structured, in-depth interviews with 5 participants who had participated at least 5 years in traditional Tai Chi. Results: Three key salient themes emerged as beneficial results of VR experiences: (1) mindfulness/ meditation, (2) enjoyment, and (3) physical exercise. Participants also reported 3 main challenges: (1) some difficulties with controllers and functions, (2) cybersickness/pain, and (3) absence of group synergy. Conclusions:These challenges suggest further avenues of investigation for researchers in refining this approach.

Cholinesterase (ChE) and monoamine oxidase (MAO) inhibitors are being used and developed to treat Alzheimer's disease (AD), a major type of dementia patients. Fifteen 4-substituted benzyl-2-triazole-linked-tryptamine-paeonol derivatives were synthesized and evaluated for their inhibitory activities against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase-A (MAO-A), and B (MAO-B). Compound 896 was the most potent BChE inhibitor (IC

Objectives: Little research has investigated the relationship between types of leisure activities and mental health outcomes among older adults with mild cognitive impairment (MCI). The purpose of this study was to investigate how certain leisure activities are associated with life satisfaction, anxiety, loneliness, happiness, and positive and negative affect. Methods: In this study, we used the 2020 Health and Retirement Study Core Early data and conducted a hierarchical regression analysis to investigate the different effects of the 3 types of leisure activities on the mental health of older adults with MCI (N=901). Results: We found that leisure-time physical activity was the strongest predictor of enhanced life satisfaction, positive affect, and happiness, and reduced anxiety and loneliness. In addition, sedentary leisure was associated with reduced anxiety and loneliness and increased happiness. Conclusions: These findings suggest that engagement in leisure-time physical activity and sedentary leisure can be instrumental in promoting the life satisfaction and mental health of older adults with mild cognitive impairment.

Layered Double Hydroxides (LDHs) are inorganic compounds of relevance to various domains, where their surface reactivity and/or intercalation capacities can be advantageously exploited for the retention/release of ionic and molecular species. In this study, we have explored specifically the applicability in the field of bone regeneration of one LDH composition, denoted “MgFeCO3”, of which components are already present in vivo, so as to convey a biocompatibility character. The propensity to be used as a bone substitute depends, however, on their ability to allow the fabrication of 3D constructs able to be implanted in bone sites. In this work, we display two appealing approaches for the processing of MgFeCO3 LDH particles to prepare (i) porous 3D scaffolds by freeze-casting, involving an alginate biopolymeric matrix, and (ii) pure MgFeCO3 LDH monoliths by Spark Plasma Sintering (SPS) at low temperature. We then explored the capacity of such LDH particles or monoliths to interact quantitatively with molecular moieties/drugs in view of their local release. The experimental data were complemented by computational chemistry calculations (Monte Carlo) to examine in more detail the mineral–organic interactions at play. Finally, preliminary in vitro tests on osteoblastic MG63 cells confirmed the high biocompatible character of this LDH composition. It was confirmed that (i) thermodynamically metastable LDH could be successfully consolidated into a monolith through SPS, (ii) the LDH particles could be incorporated into a polymer matrix through freeze casting, and (iii) the LDH in the consolidated monolith could incorporate and release drug molecules in a controlled manner. In other words, our results indicate that the MgFeCO3 LDH (pyroaurite structure) may be seen as a new promising compound for the setup of bone substitute biomaterials with tailorable drug delivery capacity, including for personalized medicine.

DNA double-strand break (DSB) repair via homologous recombination is initiated by end resection. The extent of DNA end resection determines the choice of the DSB repair pathway. Nucleases for end resection have been extensively studied. However, it is still unclear how the potential DNA structures generated by the initial short resection by MRE11-RAD50-NBS1 are recognized and recruit proteins, such as EXO1, to DSB sites to facilitate long-range resection. We found that the MSH2-MSH3 mismatch repair complex is recruited to DSB sites through interaction with the chromatin remodeling protein SMARCAD1. MSH2-MSH3 facilitates the recruitment of EXO1 for long-range resection and enhances its enzymatic activity. MSH2-MSH3 also inhibits access of POLθ, which promotes polymerase theta-mediated end-joining (TMEJ). Collectively, we present a direct role of MSH2-MSH3 in the initial stages of DSB repair by promoting end resection and influencing the DSB repair pathway by favoring homologous recombination over TMEJ.

This study aimed to empirically analyze the effect of board characteristics on the relationship between managerial overconfidence and audit report lag. Managerial overconfidence was measured according to the method proposed by Schrand and Zechman (2012). The study sample comprised 4,179 firm-year observations listed on the Korea Composite Stock Price Index from 2011 to 2017. The results of the analysis were as follows. First, there was a significant positive correlation between managerial overconfidence and audit report lag. Second, the larger the board size, the more it mitigated the relationship between managerial overconfidence and audit report lag. Third, as the ratio of outside directors on the board increased, the positive relationship between managerial overconfidence and audit report lag decreased. This study is meaningful because it directly examined how the complex relationship between the characteristics of managers and the characteristics of the board of directors affects audit report lag. Managerial overconfidence increased the firm's audit risk and acted as a determinant of audit performance, and, by suggesting that it results in an increase in audit effort, the results of this study have implications for supervisory agencies, auditors, and audit target companies. In addition, the study is meaningful because it suggests that the characteristics of the board of directors can reduce audit risk by functioning as an excellent corporate governance structure.

In tumors, the metabolic demand of cancer cells often outpaces oxygen supply, resulting in a gradient of tumor hypoxia accompanied with heterogeneous resistance to cancer therapeutics. Models recapitulating tumor hypoxia are therefore essential for developing more effective cancer therapeutics. Existing in vitro models often fail to capture the spatial heterogeneity of tumor hypoxia or involve high-cost, complex fabrication/handling techniques. Here, we designed a highly tunable microfluidic device that induces hypoxia through natural cell metabolism and oxygen diffusion barriers. We adopted a cleanroom-free, micromilling-replica-molding strategy and a microfluidic liquid-pinning approach to streamline the fabrication and tumor model establishment. We also implemented a thin-film oxygen diffusion barrier design, which was optimized through COMSOL simulation, to support both two-dimensional (2-D) and three-dimensional (3-D) hypoxic models. We demonstrated that liquid-pinning enables an easy, injection-based micropatterning of cancer cells of a wide range of parameters, showing the high tunability of our design. Human breast cancer and prostate cancer cells were seeded and stained after 24 h of 2-D and 3-D culture to validate the natural induction of hypoxia. We further demonstrated the feasibility of the parallel microfluidic channel design to evaluate dual therapeutic conditions in the same device. Overall, our new microfluidic tumor model serves as a user-friendly, cost-effective, and highly scalable platform that provides spatiotemporal analysis of the hypoxic tumor microenvironments suitable for high-content biological studies and therapeutic discoveries.

We show that the similarity of a firm’s technological expertise with that of other firms affects managerial labor market outcomes. Using each firm’s patent portfolio to estimate its technological expertise, we find that its similarity in technological expertise with other firms is strongly related to the benchmark group used for CEO compensation and job transitions. Furthermore, we show that a firm’s CEO pay is positively associated with the CEO compensation levels of technologically similar firms. Our results thus demonstrate the crucial role of technological similarity in determining the value of outside options and the boundaries of the managerial labor market.