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Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by Dabie bandavirus, which belongs to the genus Bandavirus, family Phenuiviridae, and order Bunyavirales. It has been found in tick species, various animals, and humans. The aim of this study was to detect RNA of antigens and antibodies against SFTS virus (SFTSV) among poultry such as chickens, ducks, and wild geese from five provinces in the Republic of Korea (ROK). Materials and Methods: A one-step reverse transcriptase (RT)–PCR and nested PCR were performed after viral RNA extraction. The phylogenetic tree was constructed after sequencing data were analyzed and aligned. An indirect enzyme-linked immunosorbent assay (ELISA) and a neutralization test (NT) were performed to test for IgG antibodies of SFTSV. Results: Of a total of 606 poultry serum samples collected, 568 and 539 serum samples were used to perform ELISA and NT, respectively. Of a total of 606 serum samples tested by RT-PCR targeting the S segment, 15 (2.5%) were positive for SFTSV. From the 15 positive serum samples for the SFTSV antigen, three from chickens, three from ducks, and one from wild geese were classified as genotype B-2; one from chickens was classified as genotype B-3; and three from chickens and four from wild geese were classified as genotype D. Of the 568 serum samples tested by ELISA, 83 (28.0%) from chickens, 81 (32.9%) from ducks, and 8 (30.8%) from wild geese were seropositive. Of the 539 serum samples for which an NT was performed, 113 (38.6%) from chickens and 75 (30.5%) from ducks were positive for SFTSV antibodies. Conclusions: The results of this study provide useful information regarding detection of SFTSV RNA and antibodies among poultry and the possibility of SFTSV transmission in various types of poultry, including chickens, ducks, and wild geese, in the ROK. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging zoonotic tick-borne disease in East Asia caused by the SFTS virus (SFTSV). It is to investigate the presence of SFTSV RNA and antibodies in horses from a slaughterhouse and equestrian centers in the Republic of Korea (ROK). A prevalence study of SFTSV-specific RNA and antibodies was designed from 889 horses in the ROK. Materials and Methods: Serum samples were collected from horses at a slaughterhouse and equestrian centers from 2018 to 2020. To detect the presence of SFTSV, RNA was extracted from the serum samples, and a nested reverse transcription-polymerase chain reaction (RT-PCR) was conducted. Sequencing data were analyzed, and a phylogenetic tree was constructed using the maximum-likelihood method with Molecular Evolutionary Genetics Analysis Version 7.0 software. The horse sera were also tested for SFTSV-specific immunoglobulin G antibodies using enzyme-linked immunosorbent assay (ELISA). Results: Twelve of 889 (1.3%) horse sera were positive for SFTSV RNA, and 452 of 887 (51.0%) horse sera were seropositive by ELISA. Among the RT-PCR-positive samples, 12 of the SFTSV S-segment sequences were classified as sub-genotypes B-2 (n = 6) and B-3 (n = 6). ELISA analysis was evaluated by comparison with neutralization test. We investigated SFTSV infection in horses over a 3-year period, but sampling was not performed evenly by season; continuous surveillance of SFTSV in horses is needed. Conclusions: We report the detection of SFTSV RNA and provide serological data on SFTSV prevalence in horses in the ROK. The detection of SFTSV-specific RNA and antibodies in horses, which are in close proximity to humans, suggests that SFTS is an emerging and important health issue, indicating that more attention to its relevance for equestrian workers is needed. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome virus (SFTSV) is a viral pathogen causing significant clinical signs from mild fever with thrombocytopenia to severe hemorrhages. World Health Organization has paid special attention to the dramatic increase in human SFTS cases in China, Japan, and South Korea since the 2010s. The present study investigated the molecular evolution and genetic reassortment of SFTSVs using complete genomic sequences. Methods/Principal finding: We collected the complete genome sequences of SFTSVs globally isolated until 2019 (L segment, n = 307; M segment, n = 326; and S segment, n = 564) and evaluated the evolutionary profiles of SFTSVs based on phylogenetic and molecular selection pressure analyses. By employing a time-scaled Bayesian inference method, we found the geographical heterogeneity of dominant SFTSV genotypes in China, Japan, and South Korea around several centuries before and locally spread by tick-born spillover with infrequent long-distance transmission. Purifying selection predominated the molecular evolution of SFTSVs with limited gene reassortment and fixed substitution, but almost all three gene segments appeared to harbor at least one amino acid residue under positive selection. Specifically, the nonstructural protein and glycoprotein (Gn/Gc) genes were preferential selective targets, and the Gn region retained the highest number of positively selected residues. Conclusion/Significance: Here, the large-scale genomic analyses of SFTSVs improved prior knowledge of how this virus emerged and evolved in China, Japan, and South Korea. Our results highlight the importance of SFTSV surveillance in both human and non-human reservoirs at the molecular level to fight against fatal human infection with the virus. Author summary: SFTSV causes a high mortality disease in humans, especially in China, Japan, and South Korea. For a better understanding of the evolutionary characteristics of SFTSVs, our study performed phylogenetic and genetic reassortment analyses using the largely collected genomic information of SFTSVs. It appeared that dominant endemic SFTSVs in China, Japan, and South Korea likely diverged several centuries ago. Movement of vector (e.g., tick) or non-human mammalian reservoirs possibly played a key role in human SFTSV spillover and infrequently led to international spread among three countries. Purifying selection strongly limited the generation of novel variants through either molecular mutations or genetic reassortment. However, we observed a few amino acid sites under positive selection, especially in glycoproteins which might limitedly allow the generation of variants within a clade, in which molecular evolution might not be a major cause for the current emergence of SFTSVs but the ecological or epidemiological change possibly be a more plausible factor. However, we should still carefully monitor the evolutionary dynamics of SFTSV considering the potential of host adaptation in humans. [ABSTRACT FROM AUTHOR]

Cnidium officinale Makino, a perennial crop in the Umbeliperae family, is one of Korea's representative forest medicinal plants. However, the growing area of C. officinale has been reduced by plant disease and soil sickness caused by fusarium wilt. This study isolated rhizosphere bacteria from C. officinale, and their antagonistic activity was evaluated against Fusarium solani. Particularly, four isolated strains, namely, PT1, ST7, ST8, and SP4, showed a significant antagonistic activity against F. solani. An in planta test showed that the mortality rates of shoots were significantly low in the PT1-inoculated group. The fresh and dry weights of the inoculated plants were also higher than that of the other groups. The 16S rRNA gene sequencing identified the strain PT1 as Leclercia adecarboxylata, and downstream studies confirmed the production of antagonism-related enzymes such as siderophore and N-acetyl-β-glucosaminidase. The phosphorous solubilizing ability and secretion of related enzymes were also analyzed. The results showed that PT1 strain could be utilized as promising plant growth-promoting rhizobacteria (PGPR) and biocontrol agents (BCAs). [ABSTRACT FROM AUTHOR]

We examine whether board demographic diversity enhances cognitive diversity (measured as director dissent in the boardroom) and monitoring. At the director level, we find that individual directors who are dissimilar relative to other board members in terms of tenure and experience are more likely to dissent. At the board level, boards composed of directors who have heterogenous tenure, experience, and gender are more likely to dissent. We also find that stock market reactions to director resignation announcements are more negative for directors who have ever dissented than for other directors. Moreover, following dissent-driven proposal rejections, firms experience an improvement in value and internal governance and a decrease in risk. The results suggest that directors who have diverse qualifications and skillsets as well as the inclusion of female directors enhance cognitive diversity, and that this enhanced cognitive diversity helps increase firm value and monitoring effectiveness. JEL Classifications: G30; G32; G34. [ABSTRACT FROM AUTHOR]

Purpose: We performed a nationwide epidemiological study of testicular torsion using the National Health Insurance System database for the entire male population of Korea. Materials and Methods: Age, sex, socioeconomic status, regional information, and diagnostic codes were retrieved from January 2009 to December 2019. To clearly identify the diagnosis of testicular torsion, patients who had not undergone orchiectomy or orchiopexy were excluded from the study. Multivariable logistic regression models were used to analyze the association between demographic characteristics and testicular loss. Results: The overall incidence of testicular torsion in males was 2.02 cases per 100,000 person-years and 6.99 cases per 100,000 person-years in males under 19 years of age. Testicular torsion most commonly occurred either in infancy or adolescence. The total testicular salvage rate was 75.22% and highest in children at 79.91%. The rate of orchiectomy was high in infancy and in the oldest patients. We determined that age distribution was related to the risk of testicular loss. Conclusions: This study is the first nationwide epidemiological study of testicular torsion, which contains the entire Korean population. Although the testicular salvage rate in Korea was higher compared to other countries, it is necessary to educate males under 19 years of age on the seriousness of acute testicular pain to minimize the possibility of testicular loss. [ABSTRACT FROM AUTHOR]

Incineration plants using solid refused fuel (SRF) should control their air pollution materials to minimize environmental impact. This study evaluated the emission of polychlorinated dibenzo-p-dioxin/dibenzofurans (PCDD/DFs) congener patterns in seven commercial incineration plants in Korea using SRF and biomass SRF (bio-SRF). We examined the reduction rate differences of PCDD/DFs, depending on the air pollutant control device. All seven incineration plants sufficiently managed their dioxin emissions. However, both SRF and bio-SRF incineration plants showed active chlorination reactions and resulted in a large amount of highly chlorinated dioxins. The average dioxin concentration was 0.02 ng international toxic equivalency quantity (I-TEQ)/Sm3. Ratios of 1,2,3,4,6,7,8-HpCDF and 1,2,3,7,8-PeCDF were high in the waste heat boilers of both SRF and bio-SRF incineration plants. The octachlorinated dibenzofuran (OCDF) ratio was only high in the SRF incineration plants. Octachlorodibenzo-p-dioxin (OCDD) and OCDF exhibited high dioxin ratios. SRF incineration plants had a low ratio of OCDF to 1,2,3,4,6,7,8-HpCDF. In addition, the reduction rate of PCDD/DFs was substantially high after treatment with the air pollutant control device. [ABSTRACT FROM AUTHOR]

Purpose: We investigated treatment satisfaction with flexible-dose fesoterodine in patients with overactive bladder (OAB) who were dissatisfied with previous anticholinergic therapy.Materials and Methods: The subjects were prescribed fesoterodine 4 mg for 4 weeks and fesoterodine 4 mg or 8 mg for another 8 weeks. The primary end point of this study was patients' satisfaction after 12 weeks of fesoterodine treatment on a five-point Likert scale. Secondary end points included a change in the number of daytime micturition, urgency incontinence episodes, urgency episodes, and nocturnal micturition in a 24-hour period from baseline to final assessment.Results: Overall, 84 patients were assigned to the treatment group in this study and 63 patients completed the 12-week treatment course. A final fesoterodine dose of 4 mg and 8 mg was used by 45 (71.4%) and 18 (28.6%) patients, respectively. The satisfaction and dissatisfaction rates at 12 weeks were 69.9% and 14.2%, respectively. Mean changes in the daytime micturitions (9.73 ± 4.72 vs. 7.76 ± 2.86), urgency episodes (7.73 ± 5.68 vs. 3.71 ± 4.09), and nocturnal micturitions (2.13 ± 1.36 vs. 1.68 ± 1.12) in 24 hours improved significantly with flexible-dose fesoterodine treatment (P < .05). Most adverse events were mild and none were severe.Conclusion: The flexible dose fesoterodine represents an alternative treatment modality in patients with OAB who are dissatisfied with previous anticholinergic therapy in Korea. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) metastases from epithelial ovarian cancer (EOC) are rare. We investigated the clinico-pathological prognostic factors of patients with CNS metastases from EOC and compared the outcomes of various treatment modalities. We retrospectively reviewed the records of patients with CNS metastases from EOC between 2000 and 2020. Information on the clinical and pathological characteristics, treatment, and outcomes of these patients was retrieved from Samsung Medical Center and National Taiwan University Hospital. A total of 94 patients with CNS metastases were identified among 6,300 cases of EOC, resulting in an incidence of 1.49%. Serous histological type [hazard ratio (HR): 0.49 (95% confidence interval [CI] 0.25-0.95), p =0.03], progressive disease [HR: 2.29 (95% CI 1.16-4.54), p =0.01], CNS involvement in first disease relapse [HR: 0.36 (95% CI 0.18-0.70), p =0.002], and gamma knife radiosurgery (GKS)-based combination treatment for EOC patients with CNS lesions [HR: 0.59 (95% CI 0.44-0.79), p <0.001] significantly impacted survival after diagnosis of CNS metastases. In a subgroup analysis, superior survival was observed in patients with CNS involvement not in first tumor recurrence who underwent GKS-based combination therapeutic regimens. The survival benefit of GKS-based treatment was not significant in patients with CNS involvement in first disease relapse, but a trend for longer survival was still observed. In conclusion, GKS-based combination treatment can be considered for the treatment of EOC patients with CNS metastases. The patients with CNS involvement not in first disease relapse could significantly benefit from GKS-based combination strategies. [ABSTRACT FROM AUTHOR]

Ticks and tick-borne diseases are important issues worldwide because of their effects on animal and human health. The genus Ornithodoros, which is included in the family Argasidae, is typically associated with wild animals, including seabirds. In this study, samples from the nests of seabirds and surrounding soil were collected to investigate Ornithodoros spp. from 9 uninhabited islands in the western, eastern, and southern parts of Korea from April 2017 to October 2018. The islands are known as the breeding places of migratory and resident birds. Ticks were collected from soil and nest material of seabirds using a Tullgren funnel and identified using 16S rRNA and the cytochrome c oxidase 1 gene (COI), and host animals of soft ticks were identified using the mitochondrial DNA cytochrome b gene by a polymerase chain reaction. In the sequence identity of the 16S rRNA gene fragment of Ornithodoros sp., Ornithodoros sawaii was identified as the closest homologous sequence, and the new Ornithodoros sp. was newly identified. We found that the newly identified Ornithodoros sp. in the Republic of Korea was located in uninhabited islands used as breeding places by the black-tailed gull, Larus crassirostris. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging viral disease in East Asian countries, including China, Japan, and the Republic of Korea (ROK). The causative agent of SFTS is the SFTS virus (SFTSV), which is transmitted by ticks. To investigate the prevalence of SFTSV in the ROK, a total of 9744 ticks were collected from vegetation in five national parks between July and November 2015. Of the collected adult and nymph ticks, Haemaphysalis longicornis (68.44%) was the most abundant, followed by Haemaphysalis flava (29.66%), Ixodes nipponensis (1.56%), and Amblyomma testudinarium (0.34%). Collected larval ticks were of the genera Haemaphysalis (99.61%) and Ixodes (0.39%). One-step RT-PCR and nested PCR were used to detect SFTSV-specific genes from each individual adult and nymph tick and pooled larval ticks. SFTSV was detected in 4.77% (48/1006) in H. longicornis, 1.15% (5/436) in H. flava, 0% (0/23) in I. nipponensis, and 20% (1/5) in A. testudinarium. The infection rate of SFTSV in adult and nymph ticks was 3.61%. The prevalence of SFTSV in adult and nymph ticks was relatively high, compared with previous reports. In larval ticks, the minimum infection rate was 0.31%. SFTSV was detected in ticks collected from both trail and nontrail areas in the national parks, and up to 800 meters above sea level. The sequences obtained showed 99.4–99.7% homology with SFTS virus S segment sequences from Chinese and Japanese ticks. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of carnivorous Nigidius miwai was analyzed prior to a study on evolution of carnivorous pathway within the family. This species' genome had a total length of 18,462 bp (GenBank accession number: OL597607), comprising 36 genes along with 13 protein-coding genes, 21 tRNA genes, two rRNA genes, and an A + T rich region. The nucleotide composition was 37.2% A, 33.8% T, 9.2% G, and 19.8% C (GC contents 29.0%). The phylogenetic tree indicated that N. miwai is a distinctive species within Nigidiini of Lucaninae. [ABSTRACT FROM AUTHOR]

Of 103 serum samples collected from dogs in South Korea, 3 (2.9%) were positive for severe fever with thrombocytopenia syndrome virus (SFTSV) and 22 (21.4%) were positive for antibodies against SFTSV. A dog-derived isolate of SFTSV clustered with many South Korea SFTSV strains in the Japanese clade. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS) is associated with a higher risk of morbidity and/or mortality for various chronic diseases. The aim of this study was to investigate the relationships of MetS and its components with olfactory dysfunction in a representative Korean population. We analyzed the data from the Korean National Health and Nutrition Examination Survey (2008–2010). A total of 11,609 adults who underwent otolaryngological examination were evaluated. The olfactory function was classified as normosmia or hyposmia by a self-report questionnaire according to the sense problems of smell during the past 3 months. MetS was diagnosed if a participant had at least three of the following: (1) WC ≥90 cm in men and ≥80 cm in women; (2) fasting blood sugar ≥ 100 mg/dL or medication use for elevated glucose; (3) fasting triglyceride ≥ 150 mg/dL or cholesterol-lowering medication use; (4) HDL-cholesterol <40 mg/dL in men and <50 mg/dL in women or cholesterol-lowering medication use; and (5) SBP ≥ 130 mmHg and/or DBP ≥ 85 mmHg or antihypertensive drug use for patients with a history of hypertension. The prevalence of olfactory dysfunction in the study population was 6.3%. The prevalence of olfactory dysfunction was significantly higher in older people with MetS than in those without MetS in both sexes (male, 42.0 ± 3.4% vs. 34.7 ± 0.9%, p = 0.0354; female, 46.2 ± 2.8% vs. 37.8 ± 0.8%, p = 0.0026). However, elevated waist circumference, elevated fasting glucose, elevated triglycerides, reduced HDL cholesterol, elevated blood pressure, severe stress, depressed mood, and suicidal ideation were significantly associated with olfactory dysfunction only in women. After controlling for confounders, olfactory dysfunction was significantly associated with MetS (odds ratio, 1.352; 95% confidence interval, 1.005–1.820) only in women. MetS are associated with olfactory dysfunction only in Korean women. [ABSTRACT FROM AUTHOR]

Background: We investigated the relationship between olfactory dysfunction and depressive symptoms and suicidal ideation in South Korea by using data from the 2010-2011 Korea National Health and Nutrition Examination Surveys (KNHANES). Methods: Cross-sectional data of 11,972 adults who completed the KNHANES were analyzed. Results: The prevalence of olfactory dysfunction was 5.0% among the population ≥ 19 years of age. Olfactory dysfunction was significantly associated with age, alcohol consumption, waist circumference, job, education level, and rhinitis. Depressed mood for two or more continuous weeks was reported by 19.2% of participants with olfactory dysfunction and 12.8% of participants without olfactory dysfunction (p = 0.0009). Suicidal ideation was reported by 20.5% of participants with olfactory dysfunction and 14.1% of participants without olfactory dysfunction (p < 0.0001). The participants with olfactory dysfunction were at higher risk for depressed mood than were participants without olfactory dysfunction (odds ratio [OR] 1.505 [95% confidence interval [CI], 1.106-2.048]) after adjusting for confounders. The participants with olfactory dysfunction were also at higher risk for suicidal ideation (OR 1.306 [95% CI, 1.027-1.662]). Conclusion: In the Korean population, olfactory dysfunction was associated with an increased risk for depressed mood and suicidal ideation. Further epidemiologic and experimental studies are necessary to clarify the impact of olfactory dysfunction on psychological diseases. [ABSTRACT FROM AUTHOR]

This study was carried out to examine the diversity of 34 isolates collected from 11 species of leguminous trees growing in South Korea. Phylogenetic relationships between these 34 isolates and reference strains of the Azorhizobium, Bradyrhizobium, Mesorhizobium, Rhizobium and Ensifer/Sinorhizobium were analysed by using 16S rRNA gene sequences. Twenty-one isolates were related to Mesorhizobium, four isolates to Rhizobium, and nine isolates to Bradyrhizobium. But none of isolates were related to Sinorhizobium/Ensifer and Azorhizobium. Robinia pseudoacacia and Amorpha fruticosa were nodulated by various genotypes of rhizobia out of them, most of the isolates belonged to the genus Mesorhizobium. The isolates from Lespedeza bicolar belonged to diverse genera of Mesorhizobium, Rhizobium, and Bradyrhizobium. The isolates from Maackia amurensis and Lespedeza maximowiezii var. tomentella were phylogenetically related to the genera of Bradyrhizobium. PCR-based RAPD method and phylogenetic analysis of the 16S rRNA results revealed a high phylogenetic diversity of rhizobial strains nodulating leguminous trees in South Korea. Also, the relationships between host and bacterial phylogenies showed that only Robinia pseudoacacia, and Wisteria floribunda have significantly unique branch length than expected by chance based on phylogenetic tree. [ABSTRACT FROM AUTHOR]

Prediction of Long-Term Outcomes of Catheter Ablation of Persistent Atrial Fibrillation. Aim: It has been demonstrated that atrial fibrillation (AF) frequently recurred after cardioversion (CV) using direct current (DC) or radiofrequency catheter ablation (RFCA) in patients with persistent (PeAF) or longstanding persistent AF (LPAF). We hypothesized that the atrial substrate impeding successful CV would also produce difficulty in catheter ablation, and therefore, the outcomes of RFCA for PeAF and LPAF could be predicted by the parameters determined at the time of DC CV. Method: From 2006 to 2009, 94 patients with PeAF and LPAF who had undergone elective DC CV before RFCA were studied. The parameters associated with DC CV, including number of shocks, cumulative energy adjusted, highest energy adjusted, with or without intravenous amiodarone use, and other clinical parameters were assessed. Result: Thirty-two out of the 94 patients (34%) experienced AF recurrence during the follow-up of 19.8 ± 12.3 months after RFCA. The average time to recurrence of AF after RFCA was 9.2 ± 3.2 months. Of the 62 patients, 29 patients (31%) remained sinus rhythm (SR) without antiarrhythmic drug (AAD). The patients who maintained SR had smaller body mass index (BMI) (P = 0.048), shorter duration of AF (P = 0.012), and lower prevalence of diabetes mellitus (P = 0.023) compared with patients in whom AF recurred. Total number of shocks, total energy, and highest shock energy during CV were lower (P < 0.001, P = 0.002, P = 0.048, respectively) in patients with SR during the follow-up. The outcome in patients who used amiodarone IV prior to CV, however, was not different from that in those who did not use amiodarone IV. Conclusion: DC energy parameters for successful CV before RFCA were useful to predict the long-term outcome after RFCA in patients with PeAF and LPAF. The presence of the atrial substrate making DC CV difficult might reflect atrial substrate that subsequently related to the recurrence of AF after RFCA in chronic AF. These DC energy parameters may be related to the chronicity or electroanatomical remodeling of AF. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1165-1170, November 2012) [ABSTRACT FROM AUTHOR]

We compared the characteristics of a Korean adult population diagnosed with diabetes using only a fasting plasma glucose criterion or an HbA1c criterion. The single difference between these two groups was age. Further studies should be undertaken to clarify whether age-specific diagnostic criteria would be appropriate in Korean populations. [ABSTRACT FROM AUTHOR]

The objective of the present study was to develop a concoction of natural products that could dramatically improve immune function with minimal possible side effects. Sasa quelpaertensis Nakai and Ficus erecta var. sieboldii are plants that are native to Jeju Island, Korea and are known to be rich in physiologically active substances. We prepared a mixture of different proportions and extraction conditions using two natural plants and determined their optimum mixing ratio and extraction method by assessing immune function-related biomarkers in RAW264.7 macrophages. Optimal extract (HR02/04(8:2)-W) was selected from in vitro experiments and its immunity-enhancing efficacy was evaluated in mice. After oral administration of extract to BALB/c mice for 2 weeks, nitric oxide production in the peritoneal exudate cells, natural killer cell cytotoxicity, cytokine expression in splenocytes, and total cell number of immune tissues and phenotype analysis were evaluated. Our results demonstrated that HR02/04(8:2)-W significantly enhanced the immune system by increasing natural killer cell activity, cytokine expression, and total number of cells in immune tissues. In conclusion, our study validates the role of HR02/04(8:2)-W in enhancing immunity and its potential development as a functional food. [ABSTRACT FROM AUTHOR]

The main objectives of this study are (1) to investigate the effects of heating and cooling on the static and dynamic residual properties of 35 MPa (5000 psi) concrete used in the design and construction of nuclear reactor auxiliary buildings in Korea; and (2) to establish the correlation between static and dynamic properties of heat-damaged concrete. For these purposes, concrete specimens (100 mm × 200 mm cylinder) were fabricated in a batch plant at a nuclear power plant (NPP) construction site in Korea. To induce thermal damages, the concrete specimens were heated to target temperatures from 100 °C to 1000 °C with intervals of 100 °C, at a heating rate of 5 °C/min and allowed to reach room temperature by natural cooling. The dynamic properties (dynamic elastic modulus and dynamic Poisson's ratio) of concrete were evaluated using elastic wave measurements (P-wave velocity measurements according to ASTM C597/C597M-16 and fundamental longitudinal and transverse resonance tests according to ASTM C215-14) before and after the thermal damages. The static properties (compressive strength, static elastic modulus and static Poisson's ratio) of heat-damaged concrete were measured by the uniaxial compressive testing in accordance with ASTM C39-14 and ASTM C469-14. It was demonstrated that the elastic wave velocities of heat-damaged concrete were proportional to the square root of the reduced dynamic elastic moduli. Furthermore, the relationship between static and dynamic elastic moduli of heat-damaged concrete was established in this study. The results of this study could improve the understanding of the static and dynamic residual mechanical properties of Korea NPP concrete under heating and cooling. [ABSTRACT FROM AUTHOR]

• Solid recovered fuel has a poor public perception and its use is declining. • To improve its quality, use, and perception, better quality test methods are needed. • There were no significant differences in sample transportation temperature. • 5 g samples were found to be more appropriate for ash content analysis. • Minimum acid digestion conditions were 600 W, 10 min of reaction time at 180 °C. Management of solid recovered fuel (SRF) in South Korea is unique from most other countries in that it is based on a single standard. All SRFs are distributed at the same price irrespective of their performance, resulting in utilization problems and a low degree of acceptance among consumers. Moreover, the difficulty of temperature maintenance during transportation, excessive ash content, and the use of inappropriate microwave acid digestion methods pose challenges to SRF reliability. To address these issues, we compared the relevant management statuses in South Korea with those of the international community and reviewed the effects of the transportation temperature, ash content, and microwave acid digestion technique. The moisture, ash, sulfur, and chlorine contents as well as the lower heating values (LHVs) of all the samples from South Korea were found to be below the standard [international] thresholds, and they were barely influenced by the transportation temperature. In addition, 5 g samples were found to be more appropriate for ash content analysis than the 20 g samples used in South Korea, with the former producing smaller standard deviations. The optimal microwave acid digestion conditions were also determined to be a reaction time with nitric acid of >10 min, temperature of 180 °C, and microwave power of 600 W. The results of this study highlight the need for revising the SRF test methods used in South Korea, to boost the market and enhance quality reliability. [ABSTRACT FROM AUTHOR]

Energy recovery efficiency is the main criterion determining waste disposal charges under Korean law, encouraging the use of incineration heat energy. Measures to improve the energy recovery efficiency of incineration facilities are desirable as they can reduce waste disposal charges. To derive energy recovery efficiency objectively—providing direct financial benefits—its calculation formula should be reassessed continuously. Our study objective was to recalculate the heat loss modification factors of the formula for establishing the waste lower heating value (LHV), a key component of energy recovery efficiency. Sixteen municipal solid waste incineration facilities were classified by incineration type: pyrolysis/melting or general/high temperature. Instrumental measurement data for calculating the heat loss modification factors were collected, and field measurements were performed. Our heat loss modification factors for pyrolysis/melting facilities exhibited small errors (+0.4 to +3.3%) compared to the established ones. Contrastingly, in general/high-temperature facilities, our exhaust gas heat loss modification factor differed by >10% from the conventional one. Aging incineration facility infrastructure and changes in waste properties may be causal factors. This study contributes to the objective measurement of waste heat energy recovery efficiency, deriving and applying a waste LHV formula that reflects the current operational status of domestic waste incineration facilities. [Display omitted] • Heat loss modification factors are updated for calculating lower heating values. • Lower heating value (LHV) is a key component determining energy recovery efficiency. • Our updated LHV formula generates new waste incineration facility data. • Changes in incineration facility operation status over time are shown. • Regular computational updates are essential for objective LHV assessments. [ABSTRACT FROM AUTHOR]

Domestic organic waste resources have increased over the past decade and treatment of this waste via co-digested biogasification facilities is increasing annually. However, inspection standards for such facilities are not well-established. Herein, we aimed to derive calculation formulas and factors related to organic matter decomposition efficiency and methane production rate in accordance with waste treatment facility inspection standards. We also aimed to determine the optimum waste mixing ratio. Sample (field) surveys of 18 treatment facilities and complete enumeration of 110 facilities were conducted. Calculation formulas and factors were derived using the survey data and biochemical methane potential (BMP) test. The calculated coefficients derived through the BMP test were 0.512 m3 CH 4 /kgVS in for food waste, 0.601 m3 CH 4 /kgVS in for livestock manure, and 0.382 m3 CH 4 /kgVS in for sewage sludge. The final derived calculation factors were 65.0% for food waste, 36.0% for livestock manure, and 20.0% for sewage sludge for organic matter decomposition efficiency, and 0.380 m3 CH 4 /kgVS in for food waste, 0.27 m3 CH 4 /kgVS in for livestock manure, and 0.140 m3 CH 4 /kgVS in for sewage sludge for methane production rates. The derived effective capacity calculation factors can be utilized in future waste treatment facility inspection methods by aiding in the establishment of appropriate inspection standards for co-digested biogasification facilities other than single food waste treatment facilities. In addition, the optimum mixing ratio can be used as design data for co-digested biogasification facilities. • An inspection standard for organic waste co-digestion facilities was determined • Highest methane production food waste: livestock manure: sewage sludge ratio is 0.402:0.592:0.006 • Decomposition and methane production rates used to assess suitability of facility [ABSTRACT FROM AUTHOR]

The aim of the study is to explore the correlates of indirect and direct forms of cyberbullying victimization across individual, microsystem, mesosystem, and macrosystem contexts in a nationally representative sample of South Korean youth. Data were derived from the Korean Children and Youth Rights Study, and the total sample was 10,453 adolescents. The hierarchical linear regression analyses were conducted separately for both direct and indirect cyberbullying victimization. At the individual level, no variables were found to be associated with indirect cyberbullying victimization, but male sex and depression were positively related to direct cyberbullying victimization. At the microsystem level, parental neglect was related to indirect cyberbullying victimization, while parental abuse, parental neglect, and family dysfunction were associated with direct cyberbullying victimization. Poor peer relations was significant for both indirect and direct cyberbullying victimization, and teacher abuse and school victimization were associated with victims of both types of cyberbullying. Perceived neighborhood safety had negative association with indirect and direct cyberbullying victimization. At the mesosystem level, higher levels of parental abuse and poor peer relations was related to higher risk of indirect cyberbullying victimization. Also, higher levels of family dysfunction and poor peer relations were associated with higher risk of indirect cyberbullying victimization. An assessment of the risk factors for cyberbullying victimization across multiple domains is the first necessary steps towards the development of effective intervention strategies. [ABSTRACT FROM AUTHOR]

• A CANDU severe accident analysis code, CAISER, has been developed in Korea. • A numerical simulation of the CS-28 experiment was conducted by using CAISER. • CAISER code well predicts the experimental data of CS-28. Due to the demands for an accurate and realistic severe accident code in the PHWR safety analysis, a new severe accident code called CAISER is being developed at Korea Atomic Energy Research Institute (KAERI). The CAISER code simulates core degradation phenomena occurring in a calandria tank, and it consists of two main modules: A fuel rod degradation module and a fuel channel degradation module. The fuel rod degradation module simulates the severe accident phenomena in a fuel channel, which includes a core uncovery, fuel rods heatup, hydrogen generation due to steam-Zr oxidation, fuel rods slumping, fuel rods melting and relocation, and thermal interaction of relocated molten mass with a pressure tube or a calandria tube. The fuel channel degradation module simulates the overall severe accident phenomena in a calandria tank, including the sagging of a fuel channel, debris bed formation caused by a fuel channel failure, the molten pool formation, and the calandria tank failure. Each module is tracking mass and energy changes for the main components, which are fuel, cladding, pressure tube, calandria tube in a fuel rod degradation module, and debris bed, metallic and oxidic corium pools in a fuel channel degradation module. These two modules are closely interconnected to simulate phenomena both in a fuel channel and in a calandria tank at the same time. In this paper, the numerical modelling in the CAISER code is described, including the node system and the governing equations for each main component. For the purpose of CAISER code validation, numerical simulations were conducted for the CS28-1 experiment. The simulation results show that the temperature distributions calculated by CAISER are in line with the experimental data. [ABSTRACT FROM AUTHOR]