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Background: Radial probe endobronchial ultrasound (radial EBUS) is widely used to diagnose pulmonary lesions; however, the diagnostic value of radial EBUS-guided transbronchial biopsy (TBB) varies, and its complications (especially the risk of bleeding) are not properly understood. Objectives: In this study, we evaluated the diagnostic performance and rate of complication of this procedure, and investigated the risk factors associated with the procedure-related bleeding events. Design: A retrospective cohort study. Methods: This was a retrospective study that included consecutive patients who underwent radial EBUS-guided TBB. Radial EBUS was performed under moderate sedation in inpatients or outpatients. The severity of bleeding was graded using the standardized definitions of bleeding. Results: Of 133 patients (median age, 69 years; men 57.1%) included, 41 were outpatients (30.8%). The diagnostic accuracy, sensitivity, and specificity for malignancy were 76.1% (89/117), 71.1% (69/97), and 100% (20/20), respectively. The diagnostic accuracy ranged from 66.9% to 79.0%, depending on the classification of undiagnosed cases as either false negatives or true negatives. Twenty-seven patients (20.3%) developed complications (pneumothorax, 3; pneumonia, 5; complicated pleural effusion, 2; bleeding event grade 2 or higher, 21). Of the 41 outpatients, two developed complications (pneumothorax without intervention, 1; grade 2 bleeding event, 1). Of the 21 patients (15.8%) with procedure-related bleeding events, 18 had grade 2, and three had grade 3 bleeding complications. In multivariate analysis, a large size of ⩾30 mm (adjusted odds ratio (OR), 5.09; p = 0.03) and central lesion (adjusted OR, 3.67; p = 0.03) were significantly associated with the risk of grade 2 or higher bleeding events. Conclusion: Our results suggest that radial EBUS-guided TBB is an accurate and safe method for diagnosing pulmonary lesions. Clinically significant procedure-related bleeding was rare. The central location and larger size (⩾30 mm) of pulmonary lesions were risk factors for grade 2 or higher bleeding events. [ABSTRACT FROM AUTHOR]

Purpose: The determinants that contribute to reducing stock price crash risk have garnered attention from scholars and practitioners. However, our understanding of the relationship between board diversity and stock crash risk, as well as the contextual factors that influence this relationship, remains limited. To address this gap, this study aims to investigate how different attributes of board diversity affect stock price crash risk, particularly under conditions of higher performance hazard and ownership concentration. Design/methodology/approach: Using a two-stage least squares fixed-effects estimator, the authors analyze a panel data set of 1,792 firm-year observations across 282 firms listed on the KOSPI200 from 2010 to 2019. Findings: Relation-oriented diversity reduces future stock price crash risk, particularly when firms experience performance shortfalls and have concentrated ownership structures, but task-oriented diversity has no significant effects. The results imply that only relation-oriented diversity strengthens governance mechanisms by curtailing managerial bad news withholding behaviors, and the role of relation-oriented diversity in reducing stock crash risk becomes more crucial when firms have higher performance hazard and concentrated ownership. Originality/value: This study makes crucial contributions as follows: the authors contribute to the stock crash risk literature by shifting the focus from how to when board diversity matters in assessing stock crash risk; the authors extend the board diversity research and enhance scholarly understanding of the effects of board diversity on corporate governance by highlighting that not all aspects of board diversity improve firm governance mechanisms; and the authors widen the lens from a single attribute to multiple attributes of diversity to reveal the effects of diversity on boards in assessing future crash risk. [ABSTRACT FROM AUTHOR]

Drawing on the competitive dynamics perspective, this study examines how competitive aggressiveness and complexity affect the longevity of emerging market firms. In a longitudinal and survival analysis of 570 publicly listed Korean firms from 1998 to 2017, I theorize and reveal that emerging market firms pursuing competitive aggressiveness and complexity are more likely to survive longer, particularly those competing in industries with high competitive pressure stemming from industry globalization. Broadly, I contribute to the competitive dynamics literature by extending the scholarly understanding of the long-term survival implications of firms' competitive initiatives, unveiling a new boundary condition—competitive pressure from industry globalization, and broadening the spectrum of competitive dynamics research from Western to non-Western contexts. [ABSTRACT FROM AUTHOR]

Background: The adverse effects of the COVID-19 pandemic on sleep have been well studied. However, whether the COVID-19 pandemic impacted positive airway pressure (PAP) adherence in patients with obstructive sleep apnea (OSA) remains unclear. Objectives: To evaluate the impact of the COVID-19 pandemic on adherence to PAP therapy in patients with OSA. Design: A retrospective cohort study, systematic review, and meta-analysis. Data sources and methods: The retrospective study included adults with OSA who received PAP prescriptions within the year before and the year after the start date of COVID-19 social distancing (22 March 2020) in South Korea. The threshold of clinical significance for PAP adherence was defined as 0.5 h/day. We also searched for relevant studies published up to 15 January 2023 using the MEDLINE and Embase databases. We performed a random-effects meta-analysis of our findings with the identified studies regarding the standardized mean change (SMC) with a 95% CI of PAP adherence. Results: Our study included a total of 306 patients (mean age, 59.7 years; men, 73.5%). The average daily PAP usage was 5.10 ± 1.63 h before the COVID-19 pandemic and 4.79 ± 1.96 h during the pandemic (mean difference, −0.31 h/day; 95% CI, −0.46 to −0.15 h/day; p < 0.001 using paired t -test). After identifying 10 observational before-and-after studies through a systematic review, we conducted a meta-analysis that included our original data and showed that adherence to PAP treatment was not different before and during the COVID-19 pandemic (SMC, 0.01; 95% CI, −0.18 to 0.19; p = 0.952). Conclusion: Although the COVID-19 pandemic had a statistically negative impact on adherence to PAP treatment in South Korea, the effect was not clinically relevant in patients with OSA. According to our meta-analysis, adherence to PAP treatment was not different before and during the COVID-19 pandemic in patients with OSA. Trial registration: PROSPERO database; No.: CRD42023414268; URL: https://www.crd.york.ac.uk/PROSPERO. [ABSTRACT FROM AUTHOR]

Climatic changes are now a global reality with widespread repercussions for individuals and businesses worldwide. The responsibility to adapt behaviors and protect the environment is shared by all of humanity. Business leaders can play a pivotal role in expediting this transformation by shifting their focus from pure profit-seeking to becoming value-driven entities that actively contribute to societal betterment while championing environmental conservation and sustainable profitability. This transition, however, poses certain challenges, notably the higher costs associated with ecofriendly materials, which can strain a company's financial equilibrium. Furthermore, a significant number of organizations overlook the untapped potential of their data, a valuable asset that could significantly bolster their competitive position. To address these challenges, this study aims to provide actionable guidance for business leaders by using a notable data framework to reassess their capabilities and dynamically adapt to external environments. Our method relies on data mining algorithms and business intelligence tools to report data. The results pinpoint which products are greatly in demand, so leaders can be assured their investment in redesigning products yields profit, improves product freshness, and eliminates waste. By bridging the gap between profitability and environmental responsibility, this study endeavors to empower businesses to thrive in a sustainable, value-driven future. [ABSTRACT FROM AUTHOR]

Despite the role of digital technologies in increasing the popularity of K-pop, little is known about how K-pop entertainment companies digitally transform their business models and the driving forces that shape this transformation. In this study, we present an in-depth case study of a pioneering K-pop entertainment company, SM Entertainment, whose founder's charismatic leadership and organizational capabilities contribute to the digital transformation of its business model through market-pioneering strategies and strategic learning derived from continuous interactions with changing business environments. This transition to the digital business model ultimately leads to sustainable competitive advantages in the marketplace. The important theoretical and practical implications of the findings are discussed. [ABSTRACT FROM AUTHOR]

In smart factories, where humans collaborate with robots and machines, productivity can be optimized by minimizing the distance traveled by workpieces and workers. Previous studies on this subject have largely focused on the movement of the workpieces. Therefore, this study expands on this work by accounting for the movement of the workers. In this study, the facility layout of smart factories is optimized by minimizing the distances traveled by the workpieces and workers, which is accomplished through the particle swarm optimization (PSO) algorithm. In this algorithm, each arrangement of the factory elements constitutes a unique particle, and initial particles are generated randomly using rules to be used as seeds for optimization. PSO is then executed to generate a layout that minimizes the distances traveled by the workpieces and workers. This method produces layouts that are more optimal than those in which only the distance traveled by the workpieces is considered. [ABSTRACT FROM AUTHOR]

Background: The adverse effects of the COVID-19 pandemic on sleep have been well studied. However, whether the COVID-19 pandemic impacted positive airway pressure (PAP) adherence in patients with obstructive sleep apnea (OSA) remains unclear. Objectives: To evaluate the impact of the COVID-19 pandemic on adherence to PAP therapy in patients with OSA. Design: A retrospective cohort study, systematic review, and meta-analysis. Data sources and methods: The retrospective study included adults with OSA who received PAP prescriptions within the year before and the year after the start date of COVID-19 social distancing (22 March 2020) in South Korea. The threshold of clinical significance for PAP adherence was defined as 0.5 h/day. We also searched for relevant studies published up to 15 January 2023 using the MEDLINE and Embase databases. We performed a random-effects meta-analysis of our findings with the identified studies regarding the standardized mean change (SMC) with a 95% CI of PAP adherence. Results: Our study included a total of 306 patients (mean age, 59.7 years; men, 73.5%). The average daily PAP usage was 5.10 ± 1.63 h before the COVID-19 pandemic and 4.79 ± 1.96 h during the pandemic (mean difference, -0.31 h/day; 95% CI, -0.46 to -0.15 h/day; p > 0.001 using paired t-test). After identifying 10 observational before-and-after studies through a systematic review, we conducted a meta-analysis that included our original data and showed that adherence to PAP treatment was not different before and during the COVID-19 pandemic (SMC, 0.01; 95% CI, -0.18 to 0.19; p = 0.952). Conclusion: Although the COVID-19 pandemic had a statistically negative impact on adherence to PAP treatment in South Korea, the effect was not clinically relevant in patients with OSA. According to our meta-analysis, adherence to PAP treatment was not different before and during the COVID-19 pandemic in patients with OSA. Trial registration: PROSPERO database; No.: CRD42023414268; URL: https://www.crd.york.ac.uk/PROSPERO. [ABSTRACT FROM AUTHOR]

The importance of the weapon target assignment problem is increasing as weapon systems are expected to become intelligent and unmanned on the future battlefield. This study discusses the weapon-target assignment in small-scale ground force combat, which has not been addressed much in other studies. In ground combat, target assignment means the start of an engagement, so assignment should be made taking into account not only the probability of killing an enemy but also the probability of surviving friendly forces. We introduce the WTAG (WTA ground) model that reflects these characteristics and describes methodologies for solving the problem including mixed integer nonlinear problems and Lagrangian relaxation approaches. Our finding is that the algorithm presented can efficiently provide the bounds of the problem in a practical size. [ABSTRACT FROM AUTHOR]

Background: Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure, fatal infectious complications have been reported. However, adequate preventive strategies have not been determined. We aimed to investigate the effect of chlorhexidine mouthrinse on the prevention of microbial contamination during EBUS-TBNA. Methods: In this single-center, assessor-blinded, parallel-group randomized controlled trial, we randomly assigned adult participants undergoing EBUS-TBNA using a convex probe to gargle for 1 minute with 100 mL of 0.12% chlorhexidine gluconate before EBUS-TBNA or to receive usual care (no chlorhexidine mouthrinse). Aspiration needle wash samples were collected immediately after completion of EBUS-TBNA by instilling sterile saline into the used needle. The primary outcome was colony forming unit (CFU) counts per mL of needle wash samples in aerobic cultures. Secondary outcomes were CFU counts per mL of needle wash samples in anaerobic cultures, fever within 24 hours after EBUS-TBNA, and infectious complications within 4 weeks after EBUS-TBNA. Results: From January 2021 to June 2021, 106 patients received either chlorhexidine mouthrinse (n = 51) or usual care (n = 55). The median CFU counts of needle wash samples in aerobic cultures were not significantly different in the two groups (10 CFU/mL vs 20 CFU/mL; P = 0.70). There were no significant differences between the groups regarding secondary outcomes, including median CFU counts in anaerobic cultures (P = 0.41) and fever within 24 hours after EBUS-TBNA (11.8% vs 5.6%, P = 0.31). There were no infectious complications within 4 weeks in both groups. Conclusions: Chlorhexidine mouthrinse did not reduce CFU counts in needle wash samples of EBUS-TBNA. Trial registration: ClinicalTrials.gov, NCT04718922. Registered on 22/01/2021. [ABSTRACT FROM AUTHOR]

Background: To investigate the impact of nutritional iodine deficiency on thyroid dysfunction (TD) in very low birth weight (VLBW) infants, we analyzed the association between iodine-deficient parenteral nutrition (PN) and TD requiring L-thyroxine (TD-LT4). Methods: Data of VLBW infants were obtained from the Korean Neonatal Network registry. Factors including duration of PN were analyzed according to TD-LT4. Results: TD-LT4 occurred in 490 (8.7%) of 5635 infants, and more frequently occurred in infants requiring PN for ≥4 weeks (10.2%). PN ≥ 4 weeks was one of the risk factors for TD-LT4, with an odds ratio (OR) of 1.346, p = 0.002. However, multivariate analysis showed that TD-LT4 was more of a risk for infants that were small for gestational age (OR 2.987, p < 0.001) and for other neonatal morbidities such as seizures (OR 1.787, p = 0.002) and persistent pulmonary hypertension (OR 1.501, p = 0.039) than PN ≥ 4 weeks (OR 0.791, p = 0.080). Conclusions: Prolonged iodine-deficient PN might affect TD-LT4 in VLBW infants. However, the effect of nutritional iodine deficiency on TD-LT4 risk was less than that of SGA or severe neonatal morbidities in Korean VLBW infants. [ABSTRACT FROM AUTHOR]

"EBUS-TBNA -> EBUS, TBNA" 3) B Results b , I Characteristics of participants and procedure i , third paragraph: The sentence "Cytopathology examinations revealed that 24.5 and 17.9% of the LNs or masses were malignant in the chlorhexidine group and usual care group, respectively." should be corrected to: "Cytopathology examinations revealed that 24.5% and 17.9% of the LNs or masses were malignant in the chlorhexidine group and usual care group, respectively." A total of 203 bacteria in the chlorhexidine mouthrinse group and 289 bacteria in the usual care group were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. [Extracted from the article]

Purpose: The purpose of this study is to provide the benchmarking guideline to improve managing maintenance man-hour in producing sorties of fighter jet aircraft in the Korean Air Force by measuring relative efficiency of aircraft in a fleet. Design/methodology/approach: Using actual operational data from 2014 to 2018, this paper measures the relative efficiencies of aircraft by data envelopment analysis (DEA) model. To analyze the efficiencies across different operational units and among aircraft with different attributes, non-parametric statistical techniques and tobit regression are employed. Findings: The overall management of maintenance man-hour turns out to be 63.2% efficient compared to the best practice. Operational unit possessing aircraft with different configurations shows the poorest performance implying efficiency depends on the complexity of job processes. Identification of aircraft on the best-practice frontier indicates the efficiency is closely related with the reliability of components and the age of aircraft. Practical implications: Performance of aircraft maintenance has a tremendous impact on military readiness, utilization of work force, and the quality and safety of flight operations. This study confirmed there exists plenty of room for performance enhancement and presents a reference to find a balance in the performances of maintenance practices across different installations as well as among different types of aircraft. Originality/value: Application of DEA to engineering systems has been limited in literature, especially in military operations. Thus, this study presents meaningful guidelines to which fleet manager can refer to when establishing strategic maintenance plans to balance the utilization of manpower. [ABSTRACT FROM AUTHOR]

Background: While extreme sleep duration negatively affects mortality and health-related quality of life (HRQOL) in general populations, the relationship remains uncertain in patients with chronic obstructive pulmonary disease (COPD). Objectives: To evaluate the association between sleep duration and mortality and HRQOL in patients with COPD. Methods: We analyzed 3,349 participants with COPD enrolled in the 2007–2015 Korea National Health and Nutrition Examination Survey (KNHANES). Participants aged 40 years or older with a smoking history and prebronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.7 were eligible. The participants were categorized as short sleepers (<6 h), 6–8 h, and long sleepers (>8) according to self-reported sleep duration. The outcome variables were all-cause mortality and HRQOL. HRQOL was measured using the European Quality of Life-5 Dimensions (EQ-5D) index. Results: During a median of 6.5 years, 386 (11.5%) participants died. In unadjusted Cox regression analysis, short sleepers with COPD had an increased risk of death (hazard ratio, 1.35; 95% confidence interval [CI]: 1.07–1.71). However, this association was not significant after adjusting for sociodemographic factors, BMI, FEV1, and comorbidities. In unadjusted and adjusted multiple linear regression, short sleepers had significantly worse HRQOL. The adjusted means of the EQ-5D index were 0.88 (95% CI: 0.87–0.89) for short sleepers, 0.90 (95% CI: 0.90–0.91) for 6- to 8-h sleepers, and 0.89 (95% CI: 0.87–0.91) for long sleepers (p = 0.01). Conclusions: In patients with COPD, sleep duration was not associated with all-cause mortality. However, short sleep duration was significantly associated with worse HRQOL. [ABSTRACT FROM AUTHOR]

Background: The intensive care unit (ICU) staffing model affects clinical outcomes of critically ill patients. However, the benefits of a closed unit model have not been extensively compared to those of a mandatory critical care consultation model. Methods: This retrospective before-after study included patients admitted to the medical ICU. Anthropometric data, admission reason, Acute Physiology and Chronic Health Evaluation II score, Eastern Cooperative Oncology Group grade, survival status, length of stay (LOS) in the ICU, duration of mechanical ventilator care, and occurrence of ventilator-associated pneumonia (VAP) were recorded. The staffing model of the medical ICU was changed from a mandatory critical care consultation model to a closed unit model in September 2017, and indices before and after the conversion were compared. Results: A total of 1,526 patients were included in the analysis. The mean age was 64.5 years, and 954 (62.5%) patients were men. The mean LOS in the ICU among survivors was shorter in the closed unit model than in the mandatory critical care consultation model by multiple regression analysis (5.5 vs. 6.7 days; p = 0.005). Central venous catheter insertion (38.5% vs. 51.9%; p < 0.001) and VAP (3.5% vs. 8.6%; p < 0.001) were less frequent in the closed unit model group than in the mandatory critical care consultation model group. After adjusting for confounders, the closed unit model group had decreased ICU mortality (adjusted odds ratio 0.65; p < 0.001) and shortened LOS in the ICU compared to the mandatory critical care consultation model group. Conclusion: The closed unit model was superior to the mandatory critical care consultation model in terms of ICU mortality and LOS among ICU survivors. [ABSTRACT FROM AUTHOR]

Introduction: In the general population, short and long sleep durations have been associated with adverse health outcomes. However, this association remains unclear in patients with chronic kidney disease (CKD). We examined the relationship of sleep duration to mortality and health-related quality of life (HRQOL) in individuals with CKD. Methods: A total of 1,783 adults with CKD who participated in the 2007–2015 Korea National Health and Nutrition Examination Survey were analyzed. CKD was defined as an estimated glomerular filtration rate of <60 mL/min per 1.73 m2. Participants were categorized into 3 groups according to self-reported sleep duration: <6 h (short sleepers), 6–8 h, and >8 h (long sleepers). The outcome variables were all-cause mortality and HRQOL. HRQOL was assessed using the European Quality of Life-5 Dimensions (EQ-5D) index. Results: During a median of 6.4 years, 481 (27%) deaths occurred. In unadjusted Cox regression analysis, long sleepers with CKD had an increased risk of death (hazard ratio [HR], 1.62; 95% confidence interval [CI]: 1.26–2.09). This significant association remained after adjusting for age, sex, and BMI (HR, 1.36; 95% CI: 1.05–1.75); however, it was lost after adjusting for CKD stage, social and lifestyle factors, and presence of comorbidities (HR, 1.15; 95% CI: 0.89–1.49). Compared with 6- to 8-h sleepers with CKD, long sleepers with CKD had significantly worse HRQOL in multivariable linear regression models. The adjusted means of the EQ-5D index were 0.80 (95% CI: 0.77–0.82) for short sleepers, 0.81 (95% CI: 0.80–0.82) for 6- to 8-h sleepers, and 0.76 (95% CI: 0.73–0.79) for long sleepers (p = 0.01). Discussion/Conclusion: Long sleep duration is associated with poor HRQOL in Korean adults with CKD. The weak association between long sleep duration and mortality was attenuated after multivariable adjustment in this study. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the association of sleep duration with health-related quality of life (HRQOL) and examine the influence of age, sex, and common comorbidities on this association. Methods: Using appropriate survey design, we analyzed 50,181 adults who participated in the 2007–2015 Korea National Health and Nutrition Examination Survey. Participants were categorized into five groups according to self-reported sleep duration ≤ 5 (short sleeper), 6, 7, 8, and ≥ 9 h (long sleeper). HRQOL was measured with the European Quality of Life-5 Dimensions (EQ-5D) index and visual analogue scale (VAS). Results: In multiple linear regression, short sleep duration was associated with lower EQ-5D index (β = − 0.024; 95% confidence interval [CI], − 0.027 to − 0.021) and lower EQ-VAS (β = − 3.0; 95% CI, − 3.7 to − 2.3), and long sleep duration was associated with lower EQ-5D index (β = − 0.016; 95% CI, − 0.021 to − 0.011) and lower EQ-VAS (β = − 2.2; 95% CI, − 3.1 to − 1.3) compared with 7-h sleepers. Old-age (≥ 65 years old) short and long sleepers had significantly lower EQ-5D index than those of < 65 years old. When separated according to sex, men with long sleep and women with short sleep showed the lowest EQ-5D index. Short and long sleepers with hypertension, diabetes, hypercholesterolemia, cardiovascular disease, or depression showed significantly lower EQ-5D index than those without comorbidities. Conclusions: Extreme sleep duration was associated with poor HRQOL. Short and long sleepers with old age and comorbidities had significantly lower HRQOL than those without such conditions. [ABSTRACT FROM AUTHOR]

We examine the effects of the speed of FDI expansions (SFEs) on the survival of small and medium-sized enterprises (SMEs) and the moderating role of ownership structure, highlighting how the relationship between SFEs and SME survival varies depending on the owners' identity and their potentially dissimilar interests. We argue and find in a study of Korean SMEs that the relationship between SFEs and SME survival exhibits an inverted U-shape. Moreover, SME survival peaks at a higher level of SFEs when family ownership is high, while SME survival peaks at a lower level of SFEs when institutional ownership is high. [ABSTRACT FROM AUTHOR]

Background: A three-drug regimen (macrolide, ethambutol, and rifampicin) is recommended for the treatment of Mycobacterium avium complex pulmonary disease (MAC-PD). Although macrolide has proven efficacy, the role of ethambutol and rifampicin in patients without acquired immune deficiency syndrome is not proven with clinical studies. We aimed to clarify the roles of ethambutol and rifampicin in the treatment of MAC-PD.Methods: Patients treated for MAC-PD between March 1st, 2009 and October 31st, 2018 were reviewed retrospectively. Rates of culture conversion, microbiological cure, treatment failure, and recurrence were compared according to the maintenance (≥6 months) of ethambutol or rifampicin with macrolide.Results: Among the 237 patients, 122 (51.5%) maintained ethambutol and rifampicin with macrolide, 58 (24.5%) maintained ethambutol and macrolide, 32 (13.5%) maintained rifampicin and macrolide, and 25 (10.6%) maintained macrolide only. Culture conversion was reached for 190/237 (80.2%) patients and microbiological cure was achieved for 129/177 (72.9%) who completed the treatment. Treatment failure despite ≥12 months of treatment was observed in 66/204 (32.4%), and recurrence was identified in 16/129 (12.4%) who achieved microbiological cure. Compared with maintenance of macrolide only, maintenance of ethambutol, rifampicin or both with macrolide were associated with higher odds of culture conversion [odds ratio (OR), 95% confidence interval (CI): 18.06, 3.67-88.92; 15.82, 2.38-105.33; and 17.12, 3.93-74.60, respectively]. Higher odds of microbiological cure were associated with maintenance of both ethambutol and rifampicin with macrolide (OR, 95% CI: 5.74, 1.54-21.42) and macrolide and ethambutol (OR, 95% CI: 5.12, 1.72-15.24) but not macrolide and rifampicin. Maintenance of both ethambutol and rifampicin with macrolide was associated with lower odds of treatment failure (OR, 95% CI: 0.09, 0.01-0.53) compared with macrolide only, while maintenance of one of these with macrolide was not. Maintenance of both ethambutol and rifampicin or one of these with macrolide did not decrease the probability of recurrence when compared with macrolide only.Conclusions: Maintenance (≥6 months) of ethambutol and rifampicin with macrolide was associated with the most favorable treatment outcomes among patients with MAC-PD. Given the association between ongoing ethambutol use and microbiological cure, clinicians should maintain ethambutol unless definite adverse events develop. [ABSTRACT FROM AUTHOR]

Background: The 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommends regular bronchodilator therapy in all group A patients with chronic obstructive pulmonary disease (COPD). Objective: The aim of this study was to evaluate whether regular inhaled treatment in group A patients with COPD improves their health outcomes, including exacerbations and symptoms. Methods: We recruited patients from 2 Korean prospective cohorts. Eligible COPD patients had a modified Medical Research Council (mMRC) dyspnea score of <2, a St. George's Respiratory Questionnaire for COPD (SGRQ-C) total score of <25, and had no more than 1 exacerbation and no hospitalizations during the previous year. Incidence rates of exacerbations and changes in symptom scores were analyzed. Results: After propensity score matching, there were 107 patient pairs, with and without regular inhaled treatment, who were followed up for mean times of 2.6 and 3.1 years, respectively. The incidence rates of exacerbations in those with and without regular treatment were not significantly different (incidence rate ratio 1.24 [95% CI 0.68 to 2.25]). Significant differences in favor of regular treatment were observed at 6 and 12 months for the SGRQ-C total scores (mean between-group difference –4.7 [95% CI –7.9 to –1.6] and –4.8 [95% CI –7.9 to –1.7], respectively). Regular treatment with a long-acting bronchodilator was also associated with significantly better scores on the SGRQ-C (mean between-group difference –5.0 [95% CI –8.6 to –1.4]) compared to no regular treatment at 12 months of follow-up. Conclusions: Regular inhaled treatment in group A patients with COPD was associated with a symptomatic benefit but not with a reduction of exacerbation rates. [ABSTRACT FROM AUTHOR]

Due to the undesirable implications of maritime mishaps such as ship collisions and the consequent damages to maritime property; the safety and security of waterways, ports and other maritime assets are of the utmost importance to authorities and researches. Terrorist attacks, piracy, accidents and environmental damages are some of the concerns. This paper provides a detailed literature review of over 180 papers about different threats, their consequences pertinent to the maritime industry, and a discussion on various risk assessment models and computational algorithms. The methods are then categorized into three main groups: statistical, simulation and optimization models. Corresponding statistics of papers based on year of publication, region of case studies and methodology are also presented. [ABSTRACT FROM AUTHOR]

This study examines the effects of the degree of internationalization (DOI) on the longevity of SMEs and the moderating role of tangible and intangible resources and industry globalization. Using a sample of listed Korean SMEs, we identify an inverted U-shaped curvilinear link between DOI and SME longevity. In addition, SME longevity peaks at the higher DOI when tangible and intangible resources and industry globalization are high. The findings support the liabilities of the newness and smallness perspective that an organization’s internal and external contingencies play crucial roles in achieving the optimal DOI for SME longevity. [ABSTRACT FROM AUTHOR]

This paper presents a two-phase mathematical framework for efficient power network damage assessment using unmanned aerial vehicle (UAV). In the first phase, a two-stage stochastic integer programming optimization model is presented for damage assessment in which the first stage determines the optimal UAV locations anticipating an arrival of an extreme weather event, and the second stage is to adjust the UAV locations, if necessary, when the arrival time of the predicted extreme weather becomes closer with updated information. UAV paths to scan the power network are generated in the second phase to minimize operating costs and final damage assessment completion time of the UAVs. Computational techniques are developed to help reduce the solution time. Numerical experiments show that the proposed stochastic model outperforms the deterministic counterpart in terms of the total UAV pre-positioning setup cost. Additionally, sensitivity analysis discovered the relations among damage assessment time, UAV pre-positioning setup cost, and operating cost. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to determine whether the oral administration of AD-lico™, a functional extract from Glycyrrhiza inflata in combination with 5-aminosalicylic acid (5-ASA) could ameliorate the inflammatory symptoms in dextran sulfate sodium (DSS)-induced colitis in rodents. This DSS rodent model is used to study drug candidates for colitis, as part of the spectrum of diseases falling under the inflammatory bowel disease (IBD) category. Here, with oral AD-lico™ administration, there was a substantial disruption of the colonic architectural changes due to DSS and a significant reduction in colonic myeloperoxidase (MPO) activity, a marker of colitis. In the same samples, there were also reduced levels of colonic and serum IL-6 in the oral AD-lico™ treated rats. This study also addressed the possible mechanisms for AD-lico™ mediated changes on colonic inflammation markers. These included the observations that AD-lico™ dampened the IL-6 proinflammatory-signaling pathway in THP-1 human monocytic cells and reduced the TNFα-mediated upregulation of surface adhesion molecule ICAM-1 in human umbilical vein endothelial cells (HUVECs). Finally, it was shown that AD-lico™ could be combined with 5-ASA in reducing the inflammatory markers for colorectal sites affected by colitis, a first study of its kind for a combination therapy. [ABSTRACT FROM AUTHOR]

Drawing upon the liabilities of newness and smallness perspective, we explore the impact of the degree of internationalization (DOI) on the performance of small- and medium-sized enterprises (SMEs) and the moderating impact of competitive strategies. An analysis of data from Korean SMEs reveals an S-shaped relationship between DOI and performance. Moreover, SMEs emphasizing a differentiation strategy may have better performance when increasing the DOI, whereas the opposite is true for SMEs emphasizing a cost leadership strategy. The findings support a three-stage internationalization theory in the SME context and provide a contingency perspective on the performance implications of the optimal DOI. [ABSTRACT FROM AUTHOR]

This paper addresses the drone-aided delivery and pickup planning of medication and test kits for patients with chronic diseases who are required to visit clinics for routine health examinations and/or refill medicine in rural areas. For routine healthcare services, the work proposes two models: the first model is to find the optimal number of drone center locations using the set covering approach, and the second model is the multi-depot vehicle routing problem with pickup and delivery requests minimizing the operating cost of drones in which drones deliver medicine to patients and pick up exam kits on the way back such as blood and urine samples. In order to improve computational performance of the proposed models, a preprocessing algorithm, a Partition method, and a Lagrangian Relaxation (LR) method are developed as solution approaches. A cost-benefit analysis method is developed as a tool to analyze the benefits of drone-aided healthcare service. The work is tested on a numerical example to show its applicability. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluatein vivoboth the anti-Helicobacterand the gastric-relaxing effects of AD-lico/Healthy Gut™ in rat models. AD-lico/Healthy Gut™ is a specially prepared commercial formulation ofGlycyrrhiza inflataextract that is under clinical development for indications of gastrointestinal disease and inflammatory bowel disease. In the current study, the oral administration of AD-lico/Healthy Gut™ significantly reduced mucosal damage fromHelicobacter pyloriin rats and decreased the expression of the inflammatory markers iNOS and COX-2 in the test cells. AD-lico/Healthy Gut™ also reduced mucosal damage caused by water immersion stress in rats. The accelerated gastric emptying in normal rats was also seen with AD-lico/Healthy Gut™, providing relief in gastric relaxation in the test animals. The special formulation of AD-lico/Healthy Gut™ with reduced levels of component glycyrrhizin also has benefits in minimizing the potential side effects attributed to glycyrrhizin seen with similarGlycyrrhizaextracts in terms of induction of hypokalemia and muscle weakness. The preparation has a relatively high phenolic compound content relative to other methods of preparation and is indicative of lower glycyrrhizin levels. These results suggest that AD-lico/Healthy Gut™ may provide the necessary relief from a number of stomach discomfort issues faced by a large population of people. [ABSTRACT FROM PUBLISHER]

Background: The prognostic role of epidermal growth factor receptor (EGFR) mutations in patients with lung adenocarcinomas remains controversial and the association between EGFR mutations and stage at the time of the initial diagnosis is debatable. In this study, we evaluated the association of EGFR mutations with stage at diagnosis in lung adenocarcinomas. Materials and Methods: We retrospectively analyzed 1004 consecutive patients who were diagnosed with lung adenocarcinomas and tested for EGFR mutations between June 2011 and December 2014. Results: EGFR mutations were detected in 49.2% of 1004 patients with lung adenocarcinomas. In multivariable analysis, EGFR mutations were significantly associated with early stage disease (stage I to II) at diagnosis (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.49–0.87; P = 0.003). When adjusted for age, sex, smoking status, and screening, the adjusted proportion of EGFR mutations significantly decreased according to stage. The adjusted proportions of EGFR mutations were 57.6% (95% CI, 51.7%–63.3%) for stage I, 47.9% (95% CI, 36.9%–59.0%) for stage II, 47.5% (95% CI, 39.6%–55.5%) for stage III, and 43.4% (95% CI, 38.3%–48.6%) for stage IV (P = 0.0082). Conclusions: The presence of EGFR mutations is significantly associated with early stage disease at initial diagnosis in lung adenocarcinomas after adjusting for age, sex, smoking status, and screening. This finding implies that EGFR mutations may play a role as a positive prognostic marker. [ABSTRACT FROM AUTHOR]

Providing surveillance to maritime infrastructures against imminent threats is studied in this paper. Surveillance is achieved with the aid of optimally placed sonars. Under a budget-limited deployment strategy involving both static and mobile sonars, a new optimization model using hexagonal grid systems is proposed. Numerical results suggest our approach delivers acceptable detection coverage under a multi-period placement scheme. [ABSTRACT FROM AUTHOR]

A method for the synthesis of C-3 alkenylated phosphachromones was developed using a direct intermolecular C-3 alkenylation with activated and non-activated alkenes through C–H activation under aerobic conditions. [ABSTRACT FROM AUTHOR]

No studies on idiopathic pulmonary fibrosis (IPF) have investigated the prognostic impact of extrapulmonary cancers in patients with IPF. We aimed to determine the prognostic impact of malignancies in patients with IPF. We retrospectively reviewed the medical records of patients diagnosed with IPF between 2001 and 2015. Patients were divided into three groups: IPF without cancer (n = 440), IPF with lung cancer (n = 69), and IPF with extrapulmonary cancer (n = 70). Of the 579 patients with IPF, 139 (24%) had cancer; the three most common types were lung (11.9%), gastric (2.4%), and colorectal (1.9%). Survival was significantly worse in patients with lung cancer than in those without cancer (hazard ratio [HR] = 1.83, 95% confidence interval [CI], 1.35–2.48) or those with extrapulmonary cancer (HR = 1.70, 95% CI, 1.14–2.54). The rate of hospitalisation for cancer-related complications was significantly higher in IPF patients with lung cancer than in those with extrapulmonary cancer. The annual rates of decline in percent predicted forced vital capacity and diffusion capacity for carbon monoxide did not differ among the groups. Physicians should pay attention to the development and progression of cancer and its prognostic impact in patients with IPF. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the prevalence of patients at a high risk of having OSA by using a screening questionnaire and to investigate whether the questionnaire can predict patients who are at risk of cardiopulmonary events occurring during a bronchoscopy under sedation. We prospectively enrolled consecutive adult patients who underwent flexible bronchoscopies under moderate sedation. The snoring, tiredness, observed apnea, high blood pressure-body mass index, age, neck circumference and gender (STOP-Bang) questionnaire was used to identify patients at a high (score ≥ 3 of 8) or low risk (score < 3 of 8) of having OSA. The cardiopulmonary events included hypoxemia and hypotension. Multivariable logistic regression was performed with variables selected by the least absolute shrinkage and selection operator. The prevalence of a STOP-Bang score of ≥ 3 was 67.2% (195/290), and 36.9% (107/290) experienced cardiopulmonary events. The multivariable analysis adjusting for chronic obstructive pulmonary disease, chronic kidney disease, baseline SpO2, and procedure time revealed that a STOP-Bang score of ≥ 3 was significantly associated with cardiopulmonary events in a subgroup of patients without a history of cerebrovascular disease (adjusted odds ratio, 1.94; 95% confidence interval, 1.06–3.54). The STOP-Bang questionnaire can predict cardiopulmonary events occurring during this procedure. Trial registration: NCT03325153. [ABSTRACT FROM AUTHOR]

Background: All-cause mortality risk and causes of death in bronchiectasis patients have not been fully investigated. The aim of this study was to compare the mortality risk and causes of death between individuals with bronchiectasis and those without bronchiectasis.Methods: Patients with or without bronchiectasis determined based on chest computed tomography (CT) at one centre between 2005 and 2016 were enrolled. Among the patients without bronchiectasis, a control group was selected after applying additional exclusion criteria. We compared the mortality risk and causes of death between the bronchiectasis and control groups without lung disease. Subgroup analyses were also performed according to identification of Pseudomonas or non-tuberculous mycobacteria, airflow limitation, and smoking status.Results: Of the total 217,702 patients who underwent chest CT, 18,134 bronchiectasis patients and 90,313 non-bronchiectasis patients were included. The all-cause mortality rate in the bronchiectasis group was 1608.8 per 100,000 person-years (95% confidence interval (CI), 1531.5-1690.0), which was higher than that in the control group (133.5 per 100,000 person-years; 95% CI, 124.1-143.8; P < 0.001). The bronchiectasis group had higher all-cause (adjusted hazard ratio (aHR), 1.26; 95% CI, 1.09-1.47), respiratory (aHR, 3.49; 95% CI, 2.21-5.51), and lung cancer-related (aHR, 3.48; 95% CI, 2.33-5.22) mortality risks than the control group. In subgroup analysis, patients with airflow limitation and ever smokers showed higher all-cause mortality risk among bronchiectasis patients. Therefore, we observed significant interrelation between bronchiectasis and smoking, concerning the risks of all-cause mortality (P for multiplicative interaction, 0.030, RERI, 0.432; 95% CI, 0.097-0.769) and lung cancer-related mortality (RERI, 8.68; 95% CI, 1.631-15.736).Conclusion: Individuals with bronchiectasis had a higher risk of all-cause, respiratory, and lung cancer-related mortality compared to control group. The risk of all-cause mortality was more prominent in those with airflow limitation and in ever smokers. [ABSTRACT FROM AUTHOR]

Background: Risk of exacerbations in chronic obstructive pulmonary disease (COPD) associated with biomass smoke has not been well addressed, although biomass smoke is similar in composition to tobacco smoke.Methods: To investigate whether the risk of exacerbations in COPD associated with biomass smoke differs from that in COPD associated with tobacco smoke, we recruited patients with COPD from two Korean multicenter prospective cohorts. In a multiple linear regression model, the standardized regression coefficient (β) of biomass smoke exposure ≥25 years was most similar to that (β') of tobacco smoke exposure ≥10 pack-years (β = - 0.13 and β' = - 0.14). We grouped patients with COPD into four categories based on the above cut-offs: Less Tobacco-Less Biomass, Less Tobacco-More Biomass, More Tobacco-Less Biomass, and More Tobacco-More Biomass. The main outcome was the incidence of moderate or severe exacerbations.Results: Among 1033 patients with COPD, 107 were included in Less Tobacco-Less Biomass (mean age: 67 years, men: 67%), 40 in Less Tobacco-More Biomass (mean age: 70 years, men: 35%), 631 in More Tobacco-Less Biomass (mean age: 68 years, men: 98%), and 255 in More Tobacco-More Biomass (mean age: 69 years, men: 97%). The incidence rates of exacerbations were not significantly different between Less Tobacco-More Biomass and More Tobacco-Less Biomass (adjusted incidence rate ratio, 1.03; 95% confidence interval, 0.56-1.89; P = 0.921). No interaction between sex and tobacco and biomass smoke was observed. When propensity score matching with available covariates including age and sex was applied, a similar result was observed.Conclusions: Patients with COPD associated with biomass smoke and those with COPD associated with tobacco smoke had a similar risk of exacerbations. This suggests that patients with COPD associated with biomass smoke should be treated actively. [ABSTRACT FROM AUTHOR]

The polymer binder, poly(imide-co-siloxane) (PIS), was synthesized and applied to form a thin cathode layer of composites for a thermal battery that has an unusually high operating temperature of 450 °C. The PIS was prepared through cross-linking of the polyimide with polysiloxane. The morphology of FeS2/PIS composites showed that FeS2 particles was coated with the PIS cross-linked gel. The FeS2/PIS composites enabled to fabricate mechanically stable thin cathode layer that was 10–20% of the thickness of a conventional pellet-type cathode. The FeS2/PIS composites were stable up to 400 °C and maintained their morphology at this temperature. PIS coating layers decomposed at 450 °C, and a new residue was generated, which was observed by transmission electron microscopy, and the compositional change was analyzed. The FeS2/PIS composites showed enhanced thermal stability over that of FeS2 in thermogravimetric analysis. The thermal battery with the PIS polymer binder showed a 20% discharge capacity increase when compared to a conventional pellet-type cathode. [ABSTRACT FROM AUTHOR]