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Concerns about volatile organic compounds (VOCs) have increased due to their toxicity and secondary reaction with nitrogen oxides (NOX) to form ozone (O3). In this study, passive air sampling of VOCs, O3, NO2, and SO2 was conducted in summer, fall, winter, and spring from 2019 to 2020 at six industrial and ten urban sites in Ulsan, the largest industrial city in South Korea. Over the entire sampling period, the concentration of toluene (mean: 8.75 μg/m3) was the highest of the 50 target VOCs, followed by m,p-xylenes (4.52 μg/m3), ethylbenzene (4.48 μg/m3), 3-methylpentane (4.40 μg/m3), and n-octane (4.26 μg/m3). Total (Σ50) VOC levels did not statistically differ between seasons, indicating that large amounts of VOCs are emitted into the atmosphere throughout the year. On the other hand, O3, NO2, and SO2 exhibited strong seasonal variation depending on the meteorological conditions and emission sources. The spatial distribution of Σ50 VOCs, NO2, and SO2 indicated that industrial complexes were major sources in Ulsan, while O3 had the opposite spatial distribution. Using a positive matrix factorization model, five major sources were identified, with industrial effects dominant. Aromatic compounds, such as m,p,o-xylenes, toluene, and 1,2,4-trimethylbenzene, significantly contributed to O3 formation. The VOC/NO2 ratio and O3 concentrations suggested that reducing VOC emissions is more effective than reducing NO2 emissions in terms of preventing the secondary formation of O3. The findings of this study allow for a better understanding of the relationship between VOCs, O3, NO2, and SO2 in industrial cities. [ABSTRACT FROM AUTHOR]

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease with a poor prognosis. Pirfenidone is approved and widely used for the treatment of IPF and reduces lung function decline. The aim of this study was to evaluate the efficacy of different doses of pirfenidone for the prevention of disease progression in patients with IPF. Methods: This was a prospective, observational, single-center cohort study conducted in Haeundae Paik Hospital, Republic of Korea, from April 2021 to March 2023. IPF patients were assigned to three groups according to the dose of pirfenidone (600 mg, 1200 mg, 1800 mg). Disease progression was defined as an absolute decline to ≥5% of forced vital capacity (FVC) (% predicted value) or an absolute decline to ≥10% of diffusing capacity of the lung for carbon monoxide (DLco) (% predicted value) over 12 months. The primary endpoint was to evaluate the clinical effects of pirfenidone of each dosage on disease progression in IPF patients by comparing the FVC (% predicted value) and DLco (% predicted value) values over 12 months. The secondary endpoint was to evaluate the prognostic value of Krebs von den Lungen-6 (KL-6) in the disease progression in IPF patients using the baseline KL-6 value and the change in KL-6 values between the baseline and 12 months. Results: A total of 44 patients were enrolled, of whom 39 completed the study, with 13 patients assigned to each of the three groups. The median age was 71.7 years, and 79.5% of patients were men. The baseline characteristics were similar across groups, except the 600 mg group was older (75.9 vs. 69.2 vs. 68.2 years, p = 0.016). The overall median change in FVC and DLco over 12 months was −2.7% (IQR: −9.1%, −1.2%) and −3.8% (IQR: −13.6%, −3.7%), respectively. There was no difference in the decline in FVC (change in FVC, % predicted value: −3.23 vs. −4.08 vs. −1.54, p = 0.621) and DLco (change in DLco, % predicted value: 0.00 vs. −3.62 vs. −3.15, p = 0.437) among the three groups. Fourteen patients (35.9%) suffered disease progression. The rate of disease progression did not differ according to the dose of pirfenidone (38.5 vs. 38.5 vs. 30.8%, p = 1.000). In multivariable logistic regression analysis, KL-6 was not a statistically significant predictor of disease progression. Conclusions: In our study, regardless of dose, consistent pirfenidone use for 12 months resulted in similar efficacy for the prevention of disease progression in patients with IPF. Large-scale, randomized, double-blind, placebo-controlled clinical trials are needed. [ABSTRACT FROM AUTHOR]

Industrial cities are strongly influenced by primary emissions of PM 2.5 from local industries. In addition, gaseous precursors, such as sulfur oxides (SO X), nitrogen oxides (NO X), and volatile organic compounds (VOCs), emitted from industrial sources, undergo conversion into secondary inorganic and organic aerosols (SIAs and SOAs). In this study, the spatial distributions of primary and secondary PM 2.5 in Ulsan, the largest industrial city in South Korea, were visualized. PM 2.5 components (ions, carbons, and metals) and PM 2.5 precursors (SO 2 , NO 2 , NH 3 , and VOCs) were measured to estimate the concentrations of secondary inorganic ions (SO 4 2−, NO 3 −, and NH 4 +) and secondary organic aerosol formation potential (SOAFP). The spatial distributions of SIAs and SOAs were then plotted by combining atmospheric dispersion modeling, receptor modeling, and monitoring data. Spatial distribution maps of primary and secondary PM 2.5 provide fundamental insights for formulating management policies in different districts of Ulsan. For instance, among the five districts in Ulsan, Nam-gu exhibited the highest levels of primary PM 2.5 and secondary nitrate. Consequently, controlling both PM 2.5 and NO 2 emissions becomes essential in this district. The methodology developed in this study successfully identified areas with dominant contributions from both primary emissions and secondary formation. This approach can be further applied to prioritize control measures during periods of elevated PM levels in other industrial cities. [Display omitted] • A new methodology was developed using a combined monitoring and modeling approach. • An atmospheric dispersion model was used to estimate primary PM 2.5 levels. • PM 2.5 component and precursor data were used to estimate secondary PM 2.5 levels. • The spatial distributions of primary and secondary PM 2.5 in Ulsan were visualized. • Strategies for PM 2.5 management were proposed for urban areas in each district. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo- p -dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs) were assessed in coastal sediments from industrial bays in South Korea to evaluate the pollution levels and their environmental impact. The mean sediment concentrations of Σ 17 PCDD/Fs, Σ 18 PCBs, and Σ 15 PCNs were 198 ± 140, 3427 ± 7037, and 85 ± 336 pg/g dw, respectively. Generally, pollutant concentrations in the inner bay were higher than those in the outer bay, indicating the influence of industrial emissions and harbor activities. The primary sources were identified as steel manufacturing and wastewater treatment plants for PCDD/Fs, harbor and shipbuilding activities for PCBs, and combustion-related sources for PCNs. Notably, PCDD/F concentrations exceeded sediment guideline values. The combined effects of PCDD/Fs and PCBs demonstrated adverse impacts on aquatic organisms. Hence, the release of toxic pollutants into the marine environment could have potential biological effects due to the combined impact of these various compounds. [Display omitted] • Marine sediment samples were collected from major industrial bays in South Korea. • The spatial distributions and patterns of PCDD/Fs, PCBs, and PCNs were investigated. • Pollutant concentrations were higher in inner bays near industrial facilities. • Industrial emissions, shipbuilding, and combustion were major contributors. • Potential biological impacts from various chlorinated aromatics were imminent. [ABSTRACT FROM AUTHOR]

In July 2015, one of the biggest shipbuilding and marine engineering companies in Korea, Daewoo Shipbuilding & Marine Engineering Co., LTD (DSME), suddenly reported operating losses of 2.73 billion USD, resulting in chaos and frustration of investors and market participants. The announcement of this huge loss was the result of an accounting fraud conducted by the management team. Adam Kim, the former CEO of the company, concealed 4.5 billion dollars of losses by manipulating the accounting performances. This case exemplifies the results of the weak control environment. This paper examines the consequences of the weak control environment and ineffective monitoring activities of DSME. [ABSTRACT FROM AUTHOR]

Purpose: Based on 3,775 firm-year observations from 2009 to 2013 using publicly available disclosure data for Korean listed firms, this study examines whether and how firm-level governance characteristics are associated with investment in internal auditing proxied by compensation and the number of statutory internal auditors. Design/methodology/approach: The authors investigate the association between governance characteristics and investment in internal auditing proxied by compensation and the number of statutory internal auditors. Findings: The authors find that firms with greater ownership of the largest shareholders and with a higher proportion of outside directors invest more in internal auditing. These results indicate that firms with higher incentive and demand for monitoring are more likely to invest more in internal auditing. The authors further find that the positive effect of the largest shareholder ownership (board independence) on investment in internal auditing is attenuated in firms with greater board independence (ownership of the largest shareholders) suggesting that the complementary effect of the two governance mechanisms associated with internal auditing weakens as they function simultaneously. Research limitations/implications: The results provide regulators and investors with a clear picture of the governance characteristics of firms associated with investment in internal auditing. The results imply that both the largest shareholders and the outside board of directors play a significant role in resource allocation in internal auditing within a firm. The effect of allocation, however, can be attenuated contingent upon the combined characteristics of governance mechanisms. Originality/value: Using large amounts of public archival data, this study adds to the extant literature on firm characteristics associated with investment in internal auditing. This study also contributes to the literature by expanding the scope of research on executive compensation to the locus of statutory internal auditors. [ABSTRACT FROM AUTHOR]

We examine whether labour unions influence external auditor selection and audit scope. As a major user group of financial information, labour unions likely demand financial information of high quality and thus high-quality audits. As a union's request for wage increases is likely strong when a firm is performing well, management facing wage negotiations with the labour union has incentives to manipulate earnings downward and may therefore prefer auditors who allow more discretion. Using union data unique to Korea during 2005-2008, we find that firms with a stronger labour union tend to choose higher-quality auditors (i.e. Big N or industry specialist auditors). We also find that unionization is negatively (positively) associated with positive (negative) abnormal audit fees and audit hours, and the effects are more pronounced when the union is stronger and more active. Given that departures from normal audit fees and audit hours in either direction arguably impair audit quality, this finding is consistent with our prediction of unions' demand for high-quality audits. Overall, our findings suggest that labour unions play an important role in determining audit quality. [ABSTRACT FROM AUTHOR]

To test the hypothesis that excessive amyloid deposition is a biological link between obstructive sleep apnea (OSA) and Alzheimer's disease, we determined whether OSA increases cerebral amyloid burden, relative to controls, using Pittsburgh Compound B (PiB) PET imaging. The subjects were adult participants (age 50-65 years) from the Korean Genome and Epidemiology Study. Polysomnography, brain MRI including 3D images, and a detailed neuro-cognitive function test battery were done in 2011-2012. Nineteen OSA subjects (Apnea-Hypopnea Index [AHI] ≥15/h, 21.2±5.1/h; age 58.5±4.1 years; 9 male) and 19 controls (AHI 1.8±1.3/h; age 58.5±4.2 years; 9 male) underwent 60-min dynamic 11C-PiB PET. All subjects were right-handed with normal cognitive function and brain MRI. Controls were matched by age, gender, education, and APOE genotype. A voxel-wise comparison of PiB-PET images between the two groups was performed after spatial and count normalization with cerebellar gray matter as a reference. Covariates included the status of sleep duration, hypertension, diabetes, body mass index, exercise, depressive mood, smoking, and alcohol drinking. Cortical thickness on 3D MRI was also measured and compared between the two groups. The OSA group showed a higher PiB deposition in the right posterior cingulate gyrus and right temporal cortex (corrected p < 0.05). There was no area of higher uptake in the control compared with OSA. Regional differences in cortical thickness were not significant. The study suggests that OSA accelerates amyloid deposition and may contribute to the development or progression of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

KB Kookmin Bank (KB) was the most prominent commercial bank in Korea. However, KB faced two challenges: declining firm performance and a lack of transparency in corporate governance at the level of its financial group, KB Financial Group (KBFG). By the end of 2012, KB was not a market leader in Korea any more. In addition, a conflict arose between the CEO and some members of the board of directors (BOD) of KBFG when an insider leaked private information to the International Shareholders Services (ISS). The insider reported that certain BOD members decreased firm value by disrupting the senior management's strategic plan to increase the firm's long-term competitiveness, which required attention from institutional investors. KBFG had three issues based on the inside information provided and an independent analysis. First, its CEO had been selected from outside KBFG, and he was under pressure to improve firm performance before his term was over. Second, some KBFG BOD members did not represent the interests of the company's general shareholders, including foreign institutional investors and the National Pension Services of Korea. Finally, the heavy influence of the Korean government was culturally ingrained within the corporate governance structure of KBFG. [ABSTRACT FROM AUTHOR]

Purpose Using 5,055 sample firm-years in Korea between 2009 and 2013, this paper aims to examine the association between the characteristics of the internal audit and the number of external audit hours as a proxy for audit efficiency.Design/methodology/approach This study is motivated by the International Standard on Auditing No. 610: “Using the work of internal auditors”. This auditing standard guides external auditors in using the work of internal auditors to obtain audit evidence and consult internal auditors for direct assistance. The authors expect that external audit efficiency will increase when the work of competent internal auditors is used.Findings The authors find that the number of internal auditors relative to the number of employees is associated with the number of external audit hours. This result suggests that the greater the availability of internal auditors, the greater their contribution will be to the financial statement audit and the more efficient the audit. The authors find evidence that external auditors use the work of internal auditors with accounting and legal expertise to improve audit efficiency. They also find some evidence that the work of internal auditors with greater availability is more effective during initial external audit engagements.Originality/value This study adds to the extant literature on the contributions of internal auditors to external audits by using archival data and by measuring audit effort using a large database of audit hours. In addition, our findings have practical implications for firms and external auditors who are evaluating the role and value of using the work of internal auditors. The authors also believe that the findings will be of interest to regulators or auditing standards boards. [ABSTRACT FROM AUTHOR]

This article examines the influence of majority shareholder ownership on real earnings management. It investigates whether there is a conflict between or an alignment of majority and minority shareholders' interests. If majority shareholders' interests are aligned with those of minority shareholders, a greater majority shareholder ownership lowers real earnings management. On the other hand, if they are not aligned, majority shareholders' attempts to exploit minority shareholders will increase real earnings management. This study does not find a systematic relationship between majority shareholder ownership and real earnings management. However, real earnings management significantly decreases in the upward earnings management incentive bracket as majority shareholder ownership increases. This occurs primarily because majority shareholders are more sensitive to upward real earnings management, which has a negative effect on future performance. These results suggest that the larger the ownership of majority shareholders, the more they play a positive role in mitigating real earnings management. This positive role is only effective in the post-Asian economic crisis period. These results may suggest that the economic crisis in Korea helped majority shareholders more conscious of the long-term costs of real earnings management. These findings support the convergence-of-interests hypothesis, providing evidence by investigating real earnings management instead of accruals-based earnings management. [ABSTRACT FROM AUTHOR]

This study examines the associations between the provision of tax services by incumbent auditors and earnings management. We investigate whether three different effects of tax service provision play different roles in accounting practices. The three effects include the audit independence effect, the knowledge spillover effect, and the tax avoidance effect. If the provision of tax services by incumbent auditors harms auditor independence, firms may exercise greater earnings management (audit independence effect). However, if incumbent auditors gain incremental knowledge by offering tax services, the quality of their audit services could be enhanced, and therefore, reported earnings could be more conservative (knowledge spillover effect). If tax service fee leads to low taxable income, it could depress book income when book-tax conformity is high (tax avoidance effect). We find that the provision of tax services generally improves earnings quality by curtailing opportunistic accounting practices. The results also suggest that the negative association between the provision of tax services and discretionary accruals seems to be primarily driven by the knowledge spillover effect as opposed to the tax avoidance effect. Additional analysis is conducted in examining whether the tax avoidance effect exists in a sub-sample. [ABSTRACT FROM AUTHOR]

The ability of ethambutol (EMB) to suppress bacterial resistance has been demonstrated in a time-dependent manner. Through the development of a population pharmacokinetics (PK) model, this study aimed to suggest the PK/pharmacodynamics (PD) target and identify the significant covariates that influence interindividual variability (IIV) in the PK of EMB. In total, 837 patients from 20 medical centres across Korea were enrolled in this study. The non-linear mixed-effect method was used to establish and validate the population PK model. A two-compartment model with transit compartment absorption was sufficient to describe the PK of EMB. Body weight and renal function were identified as significant covariates that affect IIV of the apparent clearance (CL/F) of EMB. Patients with moderate renal function showed 35% and 55% lower CL/F (CL/F 89.9 L/h) compared with those with mild and normal renal function, respectively. All the renal function groups with simulated doses ranging from 800 to 1200 mg achieved area under the curve over minimum inhibitory concentration (MIC) >119, and maintained T>MIC for >23 h for MIC of 0.5 µg/mL. Based on our simulation result, it is suggested that doses of 800, 1000, and 1200 mg should obtain the T>MIC target of 4, 6, and 8 h, respectively. This model was validated internally and externally. This study provides insight into the PK/PD indexes of EMB for three different renal function groups and T>MIC targets for different doses. The results could be used to provide optimal-dose suggestions for EMB. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Ojeok-san (OJS, wuji powder, goshaku-san), a widely used herbal formula in traditional Korean medicine, is used to treat illnesses such as the common cold, fatigue and gastrointestinal disorders; however there is insufficient background information about its safety. To establish safety information for OJS, we evaluated its genotoxicity. Materials and methods: The ability of OJS to induce reverse mutations was evaluated in Salmonella typhimurium (TA100, TA1535, TA98 and TA1537) and Escherichia coli (WP2uvrA) in the presence or absence of the metabolic activation system (S-9 mix). Chromosomal aberrations were evaluated in response to OJS, and viability and metaphase were analyzed in Chinese hamster lung (CHL) cells in the presence or absence of S-9 mix. A micronucleus test was performed using bone marrow cells from male ICR mice. OJS was orally administered twice at a 24h interval at a dose of 500, 1000 and 2000mg/kg in mice. Results: There were no increases in the number of revertant colonies at any concentrations of OJS regardless of S-9 mix in all tester strains compared to the vehicle control. OJS did not significantly increase the number of structural aberration in CHL cells in the presence or absence of S-9 mix. The oral administration of OJS at doses up to 2000mg/kg caused no significant increase in the number of micronucleated polychromatic erythrocytes (MNPCEs) and in the mean value for the ratio of PCE to total erythrocytes (PCE/(PCE+NCE)). NCE is normochromatic erythrocyte. OJS did not increase the incidence of MNPCEs in bone marrow. Conclusions: These results suggest that OJS is toxicologically safe on genotoxicity studies. [Copyright &y& Elsevier]

Ojeok-san (OJS; wuji powder in China and goshaku-san in Japan), a widely used herbal formula in traditional Korean medicine and Japanese herbal medicine (Kampo medicine), has been used to treat common cold and illnesses including fatigue and gastrointestinal disorders, but there is very little information on its safety. To provide information on the safety of OJS, we evaluated its acute and sub-chronic toxicity in rats. Materials and methods: The single and sub-chronic toxicity of OJS was examined using male and female Sprague-Dawley rats. The rats were treated with the OJS extract orally at the highest dose level of 2000mg/kg/day body weight. After single administration, signs of toxicity were observed every hour for the first 6h and every day for two weeks. In the sub-chronic toxicity study, OJS was administered for 13 weeks. Mortality, clinical signs, body weight changes, food and water consumption, ophthalmologic findings, urinalysis, hematological and biochemical parameters, gross findings, organ weights and histological markers were monitored during the study period. Results: We found no mortality and no abnormality in clinical signs, body weight, and necropsy findings for any of the animals in the acute and sub-chronic toxicity study following oral administration of OJS. Conclusion: OJS may not have any single dose toxicity. The lethal dose with a 50% mortality rate (LD50) was over 2000mg/kg. The no-observed adverse effects level (NOAEL) was considered to be 2000 and 1000mg/kg/day for male and female rats, respectively. [Copyright &y& Elsevier]