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The impact of Ag interlayer formation governing the intrinsic mechanical behavior of ITO/Ag/ITO thin films is proposed, which can fundamentally contribute to the robust design of advanced flexible electronics.

We developed a tool to guide decision-making for early triage of COVID-19 patients based on a predicted prognosis, using a Korean national cohort of 5,596 patients, and validated the developed tool with an external cohort of 445 patients treated in a single institution. Predictors chosen for our model were older age, male sex, subjective fever, dyspnea, altered consciousness, temperature ≥ 37.5 °C, heart rate ≥ 100 bpm, systolic blood pressure ≥ 160 mmHg, diabetes mellitus, heart disease, chronic kidney disease, cancer, dementia, anemia, leukocytosis, lymphocytopenia, and thrombocytopenia. In the external validation, when age, sex, symptoms, and underlying disease were used as predictors, the AUC used as an evaluation metric for our model’s performance was 0.850 in predicting whether a patient will require at least oxygen therapy and 0.833 in predicting whether a patient will need critical care or die from COVID-19. The AUCs improved to 0.871 and 0.864, respectively, when additional information on vital signs and blood test results were also used. In contrast, the protocols currently recommended in Korea showed AUCs less than 0.75. An application for calculating the prognostic score in COVID-19 patients based on the results of this study is presented on our website (https://nhimc.shinyapps.io/ih-psc/), where the results of the validation ongoing in our institution are periodically updated.

This paper deals with a computer vision and photosensor based two-axis solar tracking system for an active daylighting system. The real-time image processing was performed by using a Raspberry Pi 4 controller, and processed data were used as an input of an ATmega128 microcontroller to track the sun’s path. An active daylighting system requires a higher concentration of sunlight with an acceptable accuracy in different weather conditions. Alone, an image based or photosensor based control strategy cannot fulfill both requirements. Successful integration of two different feedback mechanisms could overcome the tracking difficulties. The system was composed of Raspberry Pi 4 and ATmega128 controllers, a camera, electronic circuits, and stepper motors. The proposed control system could distinguish the objects (e.g., sun or clouds) in front of the camera, and process the data required to run the solar tracker. The integration of extra photosensors and the camera was able to avoid the cloud disturbance. To investigate the efficacy of the solar tracker, it was integrated with the optical fiber cable to transmit harvested daylight for an indoor illumination.

In this study, to improve the characteristic that the waste gypsum reacts at the high temperature and high pressure when it is recycled, it was intended to develop the waste recycling method under the condition of room temperature and normal pressure. To do that, the calcium ion extraction test, and the mineralogical analysis and the structural analysis of the precipitation by the microbially induced calcite precipitation (MICP) were performed. The optimal calcium ion extraction condition was analyzed as solid-liquid ratio of 1:10, solvent type: HCl and HNO3. In addition, the air injection increased the activation of microorganism increasing the reduction of calcium ion by reaction time. Particularly, the precipitation was generated after MICP and it was confirmed that the precipitation was the calcium carbonate (CaCO3) through the mineralogical analysis and the structural analysis of the precipitation. Therefore, MICP can be utilized as a method to recycle the waste gypsum.

A fundamental understanding of the mechanical behavior of the indium tin oxide (ITO) layer is very important because cracking and delamination of the ITO layers have been a critical obstacle for mechanically robust flexible electronics. In this study, the intrinsic mechanical properties of ITO thin films without a substrate were measured by utilizing a freestanding tensile testing method. Young's modulus (89 ± 1 GPa), elongation (0.34 ± 0.02%), and tensile strength (293 ± 13 MPa) of amorphous as-deposited ITO thin films were successfully measured. The sheet resistance, transparency, and thickness of the as-deposited films were 32.9 ± 0.5 Ω/sq, 92.7% (400-700 nm), and 152 ± 6 nm, respectively. First, we investigated the effects of annealing temperature on the mechanical properties of ITO thin films. For 100- and 150 °C-annealed ITO thin films, which were amorphous, Young's modulus, elongation, and tensile strength were enhanced by increasing the packing density and reducing the structural defects. For 200 °C-annealed ITO thin films, which were polycrystalline, Young's modulus was further increased because of their highly packed crystalline nature. However, there was a significant decrease in elongation and tensile strength because grain boundaries act as critical defects. Next, the annealing time was varied from 0.5 to 6 h for a better understanding of the effects of the annealing time. As a result, the maximum elongation (0.54 ± 0.03%) and tensile strength (589 ± 11 MPa) were obtained at 150 °C for 1 h. Annealing for 1 h was appropriate for sufficient defect reduction; however, excessive annealing for more than 1 h increased the degree of partial crystallization of the ITO thin films. The proposed annealing conditions and the corresponding mechanical properties provide guidelines for the optimum annealing process of ITO thin films and quantitative data for mechanical analysis to design mechanically robust flexible electronics.

Objectives(s) The purpose of this study was to explore the experiences of women's reproductive health in North Korea through statements from North Korean female refugees. Design and sample A qualitative phenomenological study was conducted using Colaizzi's methods. Through purposive and snowball sampling, a total of eight North Korean women refugees were recruited. Measures Data were collected through in-depth, unstructured interviews with individual participants. Results A total of 18 themes, eight theme clusters, and three categories emerged. The three categories of North Korean women's reproductive health experience were: distorted sexual concepts, internalization of sexual repression, and threat of women's health rights. The study on the reproductive health experiences of North Korean women was based on the premise that their "right to health was threatened due to the internalization of sexual repression by distorted sexual concepts." Conclusion The reproductive health of North Korean women must be approached as a fundamental right, and as a human and health right.

The characteristics of bioliquid produced through the hydrothermal carbonization (HTC) of wood wastes and the effects of recirculation on hydrochar production were analyzed. The organic acids and total organic carbon of bioliquid increased with progressive recirculation, whereas intermediate byproducts decreased. Hydrochar production by bioliquid recirculation increased mass yield, carbon content, caloric value, and energy yield of the former, while improving its quality as a solid refuse fuel. We concluded that bioliquid recirculation promoted HTC, as demonstrated by Fourier-transform infrared spectroscopy. Furthermore, contrary to predictions, a relatively constant quantity of bioliquid was generated in each step, indicating that its continuous reuse is feasible. Therefore, bioliquid recirculation can improve hydrochar production while simultaneously mitigating the environmental impact of wastewater generation. This method should be considered an important strategy toward the implementation of carbon-neutrality goals.

Background This study assessed the proportion of risk-stratified Korean patients with dyslipidemia achieving their low-density lipoprotein cholesterol (LDL-C) targets as defined by the European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) (2011) guidelines while receiving lipid-modifying treatments (LMTs). Methods In this multicenter, cross-sectional, observational study, we evaluated data from Korean patients aged ≥19 years who were receiving LMTs for ≥3 months and had an LDL-C value within the previous 12 months on the same LMT. Data were collected for demographics, cardiovascular (CV) risk factors, medical history, and healthcare consumption. Patients were risk-stratified according to the ESC Systematic COronary Risk Evaluation (SCORE) chart and LDL-C target achievement rate was assessed. Results Guideline-based risk-stratification of the 1,034 patients showed the majority (72.2%) to be in the very high-risk category. Investigators' assessment of risk was underestimated in 71.6% compared to ESC/EAS guidelines. Overall LDL-C target achievement rate was 44.3%; target achievement was the highest (66.0%) in moderate-risk patients and the lowest (39.0%) in very high-risk patients. Overall 97.1% patients were receiving statin therapy, mostly as a single-agent (89.2%). High-intensity statins and the highest permissible dose of high-intensity statins had been prescribed to only 9.1% and 7.3% patients in the very high-risk group, respectively. Physician satisfaction with patients' LDL-C levels was the primary reason for non-intensification of statin therapy. Conclusion Achievement of target LDL-C level is suboptimal in Korean patients with dyslipidemia, especially in those at very high-risk of CV events. Current practices in LMTs need to be improved based on precise CV risk evaluation posed by dyslipidemia.

Anisotropic conductive films (ACFs) composed of polymer adhesive resin and conductive particles have been used as interconnection materials for ultrafine pitch chip-on-flex (COF) packages due to their flexibility, stable electrical properties, and bending reliability. To realize an efficient ultrafine pitch COF package, a new anchoring polymer layer (APL) was recently introduced. However, the chip flexibility in terms of ACFs materials after APL layer integration needs lot of improvement. Herein, we study the order to obtain more flexible and reliable COF packages using ACFs interconnection materials, and the effect of the ACFs material properties on the COF bending reliability was investigated. It was found that when the APL ACFs were used for the COF packages, 100% electric insulation rates were obtained due to the suppression of conductive particle movement by the APL structure compared with the conventional ACFs. Furthermore, the polyacrylonitrile (PAN) APL ACFs showed better ACFs joint properties and dynamic bending properties compared with the polyvinylidene fluoride (PVDF) APL ACFs due to its higher adhesion property caused by the chemical reaction between the PAN and the curing agent inside the epoxy polymer adhesive resin confirmed by the Fourier transform-infrared spectroscopy (FT-IR) analysis. In addition, the strain applied to the PAN APL ACFs joints during the bending test was 1.35% which was quite smaller than that of the PVDF APL ACFs joints, 2.01% resulting in better bending reliability too. For the bending reliability, there was no failure at the PAN APL ACFs joints up to 150 000 cycles, not only because of the excellent mechanical properties of PAN APL ACFs but also because of the lower strain applied to the APL ACFs joints during the dynamic bending test in COF packages.

BackgroundCoronary computed tomography angiography (CTA) and optical coherence tomography (OCT) provide additional functional information beyond the anatomy by applying computational fluid dynamics (CFD). This study sought to evaluate a novel approach for estimating computational fractional flow reserve (FFR) from coronary CTA-OCT fusion images.MethodsAmong patients who underwent coronary CTA, 148 patients who underwent both pressure wire-based FFR measurement and OCT during angiography to evaluate intermediate stenosis in the left anterior descending artery were included from the prospective registry. Coronary CTA-OCT fusion images were created, and CFD was applied to estimate computational FFR. Based on pressure wire-based FFR as a reference, the diagnostic performance of Fusion-FFR was compared with that of CT-FFR and OCT-FFR.ResultsFusion-FFR was strongly correlated with FFR (r = 0.836, P < 0.001). Correlation between FFR and Fusion-FFR was stronger than that between FFR and CT-FFR (r = 0.682, P < 0.001; z statistic, 5.42, P < 0.001) and between FFR and OCT-FFR (r = 0.705, P < 0.001; z statistic, 4.38, P < 0.001). Area under the receiver operating characteristics curve to assess functionally significant stenosis was higher for Fusion-FFR than for CT-FFR (0.90 vs. 0.83, P = 0.024) and OCT-FFR (0.90 vs. 0.83, P = 0.043). Fusion-FFR exhibited 84.5% accuracy, 84.6% sensitivity, 84.3% specificity, 80.9% positive predictive value, and 87.5% negative predictive value. Especially accuracy, specificity, and positive predictive value were superior for Fusion-FFR than for CT-FFR (73.0%, P = 0.007; 61.4%, P < 0.001; 64.0%, P < 0.001) and OCT-FFR (75.7%, P = 0.021; 73.5%, P = 0.020; 69.9%, P = 0.012).ConclusionCFD-based computational FFR from coronary CTA-OCT fusion images provided more accurate functional information than coronary CTA or OCT alone.Clinical Trial Registration[www.ClinicalTrials.gov], identifier [NCT03298282].

Introduction: Despite the emphasis on more systematic and high-quality health care services in the maternal period, a high maternal mortality rate in developing countries is still reported. North Korea, one of the closed countries in the world, is no exception. This study aimed to explore the maternal health experiences in North Korea. Methodology: Qualitative content analysis suggested by Graneheim and Lundman was used to analyze the data of 10 female North Korean defectors. Results: Three categories were derived: pregnancy without self-determination rights, a huge gap between the policies on maternal protection and the reality, and discriminatory childbirth and postpartum care. The theme was “perilous existence of maternal health.” Discussion: We highlighted the need for awareness of maternity protection led by health care professionals such as nurses to guarantee Universal Health Coverage as a human right for North Korean women.

Introduction: As South Korea is fast becoming an aging society, the need for integrated care of the elderly has increased. ‘Community Integrated Care Initiatives’ have been implemented by the Ministry of Health and Welfare. However, home healthcare is insufficient to meet this need. Description: The National Health Insurance Service (NHIS) launched the initiative, ‘Patient-Centered Integrated model of Home Health Care Services in South Korea (PICS-K)’. Its purpose is to coordinate home healthcare providers by establishing a home health care support center (HHSC) in public hospitals starting in 2021. The PICS-K has six main features: integration of primary care-hospital-personal care-social services through a consortium, HHSC in hospitals with primary care collaboration, increased accessibility, interdisciplinary team (IDT), patient-centeredness, and education. Discussion: >Integrating healthcare, personal care, and social services at multiple levels is necessary. Accordingly, platforms to share participant information and service records, and institutional payment system reforms are required. Conclusion: In public hospitals, the HHSC supported primary care, which provides home healthcare. The model combined community healthcare and social services to accomplish the aging-in-place of the homebound population by focusing on their needs. This model will be applicable to other regions in Korea.

IntroductionAngiography remains the gold standard for guiding percutaneous coronary intervention (PCI). However, it is prone to suboptimal stent results due to the visual estimation of coronary measurements. Although the benefit of intravascular ultrasound (IVUS)-guided PCI is becoming increasingly recognised, IVUS is not affordable for many catheterisation laboratories. Thus, a more practical and standardised angiography-based approach is necessary to support stent implantation.Methods and analysisThe Quantitative Coronary Angiography versus Intravascular Ultrasound Guidance for Drug-Eluting Stent Implantation trial is a randomised, investigator-initiated, multicentre, open-label, non-inferiority trial comparing the quantitative coronary angiography (QCA)-guided PCI strategy with IVUS-guided PCI in all-comer patients with significant coronary artery disease. A novel, standardised, QCA-based PCI protocol for the QCA-guided group will be provided to all participating operators, while the PCI optimisation criteria will be predefined for both strategies. A total of 1528 patients will be randomised to either group at a 1:1 ratio. The primary endpoint is the 12-month cumulative incidence of target-lesion failure defined as a composite of cardiac death, target-vessel myocardial infarction or ischaemia-driven target-lesion revascularisation. Clinical follow-up assessments are scheduled at 1, 6 and 12 months for all patients enrolled in the study.Ethics and disseminationEthics approval for this study was granted by the Institutional Review Board of Asan Medical Center (no. 2017-0060). Informed consent will be obtained from every participant. The study findings will be published in peer-reviewed journal articles and disseminated through public forums and academic conference presentations. Cost-effectiveness and secondary imaging analyses will be shared in secondary papers.Trial registration numberNCT02978456.

Cu pattern-laminated fabric substrates using epoxy-based B-stage adhesive films were demonstrated. Fine-pitch Cu electrical patterns were fabricated on B-stage adhesive films and then laminated to fabrics. As a result, fabric substrates having minimum Cu line width of $80~\mu \text{m}$ were successfully fabricated without any Cu lines displacement and fabric damages. First, the effects of the curing properties of adhesive films on fine-pitch Cu patterning were investigated by Fourier transform infrared (FTIR) spectroscopy and a 90° peel adhesion test. In addition, the morphology of the Cu pattern-laminated fabric substrates was observed depending on the viscosity of epoxy laminating adhesive film. Finally, the effects of film moduli on the dynamic bending fatigue properties were investigated experimentally and theoretically.

Purpose: Comprehensive nursing care services are provided for patient-centered nursing care in Korea. This study was conducted to compare differences in the frequency and elapsed time of nursing activities between comprehensive nursing care units and general medical-surgical units. Methods: This is a descriptive study design using direct observation of nursing care activities. A time and motion study on the frequency and elapsed time of nursing activities provided by nurses was conducted in the comprehensive nursing care units and general units of two small-to-medium sized hospitals. Data were collected for 64 hours in each hospital, through a two-way method using a checklist and a camera recorder. Results: The total number of nursing activities, activities provided per patient and patient safety care including clinical assessment and treatment were higher in the comprehensive nursing care units compared to general units. We found similar findings regarding the duration of nursing activities. Conclusion: Comprehensive nursing care units provide patient-centered nursing care and have a broader range of nursing activities for patient safety than general units. Assessments conducted to meet nursing needs and to promote safe nurse staffing should reflect the characteristics of the nursing tasks performed in comprehensive nursing care units.

Aqueous-processed all-polymer solar cells (aq-APSCs) are reported for the first time by developing a series of water/ethanol-soluble naphthalenediimide (NDI)-based polymer acceptors [P(NDIDEG-T), P(NDITEG-T), and P(NDITEG-T2)]. Polymer acceptors are designed by using the backbones of NDI-bithiophene and NDI-thiophene in combination with nonionic hydrophilic oligoethylene glycol (OEG) side chains that facilitate processability in water/ethanol mixtures. All three polymers exhibit sufficient solubility (20-50 mg mL-1) in the aqueous medium. The P(NDIDEG-T) polymer with shorter OEG side chains is the most crystalline with the highest electron mobility, enabling the fabrication of efficient aq-APSCs with the maximum power conversion efficiency (PCE) of 2.15%. Furthermore, these aq-APSCs are fabricated under ambient atmosphere by taking advantage of the eco-friendly aqueous process and, importantly, the devices exhibit outstanding air-stability without any encapsulation, as evident by maintaining more than 90% of the initial PCE in the air after 4 days. According to a double cantilever beam test, the interfacial adhesion properties between the active layer and electron/hole transporting layers were remarkably improved by incorporating the hydrophilic OEG-attached photoactive layer, which hinders the delamination of the constituent layers and prevents the increase of series resistance, ultimately leading to enhanced durability under ambient conditions. The combination of increased device stability and minimal environmental impact of these aq-APSCs demonstrates them to be worthy candidates for continued development of scalable polymer solar cells.

With increase in fresh water demand and lack of fresh water resources, the current water scarcity can only be solved with seawater desalination. However, due to high dependence of current desalination technologies on fossil fuels, especially in GCC countries where the share of thermal desalination systems is dominating, the environmental sustainability is at risk. Despite high operational and maintenance cost, electricity operated membrane based reverse osmosis (RO) system provides simple configuration with less capital cost. Therefore, for future sustainable desalination, more innovative and energy efficient methods have to be sought out which will not only have the low operational cost of the thermal desalination systems but they can also have simple design and fabrication cost of membrane based systems. Vacuum membrane distillation (VMD) is a thermal distillation technique that works on the vapor pressure across the hydrophobic membrane. With the introduction of heat recovery scheme within the VMD modules in form of the multi-effect VMD operation, a detailed performance analysis of the VMD system is presented in this study under different operating conditions. The performance of system is investigated on components level with comparison between single effect and multi-effect operation.

In order to mitigate primary water stress corrosion cracking (PWSCC) of dissimilar metal weld (DMW) in the primary coolant system of pressurized water reactor (PWR), a heat treatment has been considered. However, the heat treatment conditions should be carefully determined to prevent detrimental effect on the materials in the DMW region. In this study, changes in the mechanical property of materials in DMW and degree of sensitization of SS were evaluated for various heat treatment conditions. In addition, material properties variation and sensitization within the heat affected zone (HAZ) were investigated after the application of the heat treatment condition of 600 °C for 10 h, which is considered as the representative heat treatment condition. Based on the test results, it was found that the application of the representative heat treatment condition (600 °C for 10 h) would result in negligible detrimental effect on the mechanical properties of materials in DMW and sensitization of SS.