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A fungal strain designated KNUF-22-014, belonging to the family Ophiocordycipitaceae, was isolated from a soil sample collected in Sobaeksan National Park, South Korea. Phylogenetic trees based on the combined sequences of internal transcribed spacer (ITS) regions and the large subunit of 28S rRNA (LSU) gene, as well as on five concatenated loci (LSU, ITS, translation elongation factor 1α, β-tubulin, and subunit 1 of RNA polymerase II), revealed that the isolate falls within the clade containing the genus Tolypocladium but occupies a distinct phylogenetic position. Its closest relative is T. tropicale. Morphologically, strain KNUF-22-014 can be distinguished from T. tropicale by the shape of its phialides (subcylindrical vs. lageniform), its conidiophore type (arborescent or unbranched vs. trichodermatoid), and its larger conidia size (2.1 ± 0.1 µm vs. 1.5 ± 0.1 µm). Phylogenetic analysis and morphological observations indicate that KNUF-22-014 represents a novel species in the genus Tolypocladium, for which the name Tolypocladium sobaeksanense sp. nov. is proposed.

In July 2021, symptoms of soft rot were observed on the stems of Ficus carica in Yeongam, Jeollanamdo, Korea. To accurately diagnose the cause, infected stem was collected and bacterial strain was isolated. Among these, the pathogenic strain KNUB-08-21 was identified as Pectobacterium aroidearum through 16S rRNA gene sequencing and phylogenetic analysis based on the concatenated sequences of the dnaX, leuS, and recA genes. The affiliation of the isolate with this bacterial species was also confirmed by its biochemical characteristics obtained using API ID 32 GN system. Artificial inoculation confirmed the strain's pathogenicity in figs, causing significant damage to both stems and fruits. To our knowledge, this is the first report of P. aroidearum causing soft rot disease in F. carica in Korea.

In the Goesan region, located in Chungcheongbuk-do, Korea, a significant outbreak of soft rot infections was documented in August 2021, affecting fruits of Momordica charantia, commonly known as bitter melon or bitter gourd. The symptoms included a noticeable transition to yellowing in the affected fruits, eventually leading to their collapse. The bacterial strain KNUB-09-21 was isolated from the diseased fruits. Molecular analysis, using the sequences of the 16S rRNA region and three housekeeping genes (dnaX, recA, and leuS), along with the results of compound utilization in the API ID 32 GN system, provide strong evidence for the identification of the isolate KNUB-09-21 as Pectobacterium brasiliense. The pathogenicity of strain KNUB-09-21 on M. charantia was confirmed through a controlled inoculation test. Within two days, inoculated fruits displayed soft rot symptoms closely resembling those observed in naturally affected fruits. This is the first report of soft rot on M. charantia in Korea.

Zamioculcas zamiifolia is a popular indoor ornamental plant in Korea. In August 2021, a severe outbreak of soft rot disease affected Z. zamiifolia in Emseong, Chungcheongbuk-do, Korea. Infected plants displayed wilting, water-soaked lesions, stem collapse, and green-brown discoloration. The bacterial strain KNUB-05-21 was isolated from infected stems and identified as Pectobacterium aroidearum using 16S rRNA nucleotide sequencing and multilocus sequence analysis based on partial sequences of dnaX, leuS, and recA genes. Confirmation of its affiliation with P. aroidearum was also obtained through biochemical and morphological characterization. To confirm the pathogenicity of strain KNUB-05-21, its suspension was injected into Z. zamiifolia stems. Within a week, soft rot developed on the stems, exhibiting symptoms similar to those observed in field-infected plants. The reisolated strain was identical to those of P. aroidearum. Before this study, P. aroidearum was not reported as a causative pathogen of Z. zamiifolia soft rot in Korea.

Wilted and water-soaked lesion symptoms were observed on cucumbers in greenhouses located in Daejeon, Chungcheongnam-do, Korea, in June 2021. A bacterial strain, designated KNUB-04-21, was isolated from the cucumbers, which was subsequently identified as Pectobacterium brasiliense through a phylogenetic analysis based on sequences of the 16S rRNA region, dnaX, leuS, and recA genes. The biochemical characteristics of KNUB-04-21 were also similar to those of P. brasiliense through investigation using the API ID 32 GN system. The pathogenicity of KNUB-04-21 was confirmed by inoculating it into healthy cucumber plants. The reisolated strains were also found to be same to the original strain. To our knowledge, this is the first report of P. brasiliense being identified as the causative agent of cucumber soft rot in Korea.

In May 2021, characteristic soft rot symptoms, including soft, watery, slimy, black rot, wilting, and leaf collapse, were observed on melon plants (Cucumis melo) in Gokseong, Jeollanam-do, Korea. A bacterial strain, designated KNUB-06-21, was isolated from infected plant samples, taxonomically classified, and phylogeneti-cally analyzed using 16S rRNA and housekeeping gene sequencing. Strain KNUB-06-21 was also examined for compound utilization using the API ID 32 GN system and strain KNUB-06-21 was identified as Pectobacterium brasiliense. Subsequent melon stem inoculation studies using strain KNUB-06-21 showed soft rot symptoms similar to field plants. Re-isolated strains shared phenotypic and molecular characteristics with the original P. brasiliense KNUB-06-21 strain. To our knowledge, ours is the first report of P. brasiliense causing melon soft rot disease in Korea.

AbstractThe fungal strain KNUF-22-18B, belonging to Cucurbitariaceae, was discovered from a stink bug (Hygia lativentris) during the investigation of insect microbiota in Chungnam Province, South Korea. The colonies of the strain KNUF-22-18B were wooly floccose, white to brown in the center on oatmeal agar (OA), and the colonies were buff, margin even, and colorless, reverse white to yellowish toward the center on malt extract agar (MEA). The strain KNUF-22-18B produced pycnidia after 60 days of culturing on potato dextrose agar, but pycnidia were not observed on OA. On the contrary, N. keratinophila CBS 121759T abundantly formed superficial pycnidia on OA and MEA after a few days. The strain KNUF-22-18B produced chlamydospores subglobose to globose, mainly in the chain, with a small diameter of 4.4–8.8 μm. At the same time, N. keratinophila CBS 121759T displayed a globose terminal with a diameter of 8–10 μm. A multilocus phylogeny using the internal transcribed spacer regions, 28S rDNA large subunit, β-tubulin, and RNA polymerase II large subunit genes further validated the uniqueness of the strain. The detailed description and illustration of the proposed species as Neocucurbitaria chlamydospora sp. nov. from Korea was strongly supported by molecular phylogeny.

AbstractIn this study, a fungal strain KNUF-22-025 belonging to the genus Botryotrichum was isolated from the soil in Korea. The cultural and morphological characteristics of this strain differed from those of closely related species. On malt extract agar, strain KNUF-22-025 showed slower growth than most of the related species, except B. domesticum. The conidia size (9.6–21.1 × 9.9–18.4 µm) of strain KNUF-22-025 was larger than those of B. piluliferum, B. domesticum, and B. peruvianum but smaller than those of B. atrogriseum and B. iranicum. Conidiophores in strain KNUF-22-025 (137 µm) were longer than those in other closely related species but shorter than those in B. atrogriseum. Multi-locus analysis of molecular markers, such as ITS, 28S ribosomal DNA, RBP2, and TUB2 revealed that strain KNUF-22-025 was distinct from other Botryotrichum species. Thus, this strain is proposed as a novel species based on morphological characteristics along with molecular phylogeny and named Botryotrichum luteum sp. nov.

AbstractIn this study, fungal strains designated as KNUF-22-14A and KNUF-22-15A were isolated from soil samples in Korea. These two strains were identified based on cultural and morphological characteristics as well as phylogenetic analyses and were found to be morphologically and phylogenetically identical. Upon their morphological comparison with closely related species, such as Tolypocladium album, T. amazonense, T. endophyticum, T. pustulatum, and T. tropicale, a difference in the size of short phialides [0.6–2.4(–9.3) × 0.8–1.4 µm] was observed. Meanwhile, these strains had larger conidia (1.2–3.0 × 1.2–3.0 µm) than T. album, T. amazonense, T. endophyticum, and T. tropicale and smaller conidia than T. pustulatum. Phylogenetic analyses using a multi-locus datasets based on ITS, LSU, and SSU showed that KNUF-22-14A and KNUF-22-15A formed a distinct cluster from previously identified Tolypocladium species. Thus, these fungal strains isolated from soil in Korea are proposed as a novel species according to their characteristics and are named Tolypocladium globosum sp. nov.

In October 2021, soft rot disease seriously affected radish crop in Dangjin, Chungcheongnam-do, Korea. The infected radishes were stunted and turned dark green, with yellowish leaf foliage. A slimy, wet, and decayed pith region was observed in the infected roots. The bacterial strain KNUB-03-21 was isolated from infected roots. The biochemical and morphological characteristics of the isolate were similar to those of Pectobacterium brasiliense. Phylogenetic analysis based on the sequences of the 16S rRNA region and the concatenated DNA polymerase III subunit tau (dnaX), leucine-tRNA ligase (leuS), and recombinase subunit A (recA) genes confirmed that the isolate is a novel strain of P. brasiliense. Artificial inoculation of radish with P. brasiliense KNUB-03-21 resulted in soft rot symptoms similar to those observed in infected radish in the field; subsequently, P. brasiliense KNUB-03-21 was reisolated and reidentified. To our knowledge, this is the first report of P. brasiliense as a causal pathogen of radish soft rot in Korea.

In September 2021, gray-to-brown discoloration and expanding water-soaked lesions were observed on the outer and inner layers and the core of kimchi cabbage (Brassica rapa subsp. pekinensis) in fields located in Samcheok, Gangwondo, Korea. A bacterial strain designated as KNUB-02-21 was isolated from infected cabbage samples. Phylogenetic analysis based on the sequences of the 16S rRNA region and the dnaX, leuS, and recA genes confirmed that the strain was affiliated with Pectobacterium versatile. Additionally, the biochemical and morphological profiles of the isolate were similar to those of P. versatile. Based on these results, the isolate was identified as a novel strain of P. versatile. Healthy kimchi cabbage slices developed soft rot upon inoculation with P. versatile KNUB-02-21 and exhibited symptoms similar to those observed in the diseased plants in fields. The re-isolated strains were similar to those of P. versatile. Prior to our study, P. versatile as the causative pathogen of kimchi cabbage soft rot had not been reported in Korea.

AbstractThe fungal strain belonging to the genus Monochaetia of the family Sporocadaceae was isolated from hairy long-horned toad beetle (Moechotypa diphysis) during the screening of microfungi associated with insects from Gangwon Province, Korea. The strain KNUF-6L2F produced white, light brown to dirty black surface, and olivaceous green colonies with the higher growth, while the closest strain M. ilicis KUMCC 15–0520T were light brown to brown, and M. schimae SAUCC 212201T light brown to brown toward center. The strain KNUF-6L2F produced shorter (5.7–14.0 μm) apical appendages than M. ilicis (6.0–24.0 μm), but similar to M. schimae (7.0–12.5 μm). Three median cells of KNUF-6L2F were light brown to olivaceous green, whereas brown and olivaceous cells were observed from M. ilicis and M. schimae, respectively. And the strain KNUF-6L2F produced larger conidiogenous cells than M. ilicis and M. schimae. Additionally, phylogenetic analyses based on molecular datasets of internal transcribed spacer (ITS) regions, translation elongation factor 1-alpha (TEF1α), and β-tubulin (TUB2) genes corroborated the strain’s originality. Thus, the strain is different from other known Monochaetia species, according to molecular phylogeny and morophology, hence we suggested the new species Monochaetia mediana sp. nov. and provided a descriptive illustration.

The graft cactus (Gymnocalycium mihanovichii) continues to be exported to more than 20 countries worldwide. In April 2021, typical bacterial symptoms of soft rot were observed in the graft cactus (cv. Yeonbit) in Goyang, Gyeonggi-do, Korea, resulting in economic losses in cactus production. The stems turned dark brown and the flowers were covered with black rot. The bacterial strain designated as KNUB-01-21 was isolated from infected stems and flowers. The results of the morphological and biochemical tests of the isolate were similar to those of Pectobacterium brasiliense. For molecular analysis, the 16S rRNA region and three housekeeping genes (dnaX, leuS, and recA) of the strain KNUB-01-21 were amplified. Based on t he results of the molecular analysis and morphological and biochemical tests, KNUB-01-21 was identified as P. brasiliense. The pathogenicity of KNUB-01-21 on graft cactus was confirmed by an inoculation test. Artificial inoculation using P. brasiliense KNUB-01-21 produced soft rot symptoms on the grafted cactus, and the same bacterium was re-isolated and re-identified. This is the first report of P. brasiliense causing soft rot in graft cactus in Korea.

Mapping three-dimensional (3D) surface deformation caused by an earthquake is very important for the environmental, cultural, economic and social sustainability of human beings. Synthetic aperture radar (SAR) systems made it possible to measure precise 3D deformations by combining SAR interferometry (InSAR) and multiple aperture interferometry (MAI). In this paper, we retrieve the 3D surface deformation field of the 2010 Haiti earthquake which occurred on January 12, 2010 by a magnitude 7.0 Mw by using the advanced interferometric technique that integrates InSAR and MAI data. The surface deformation has been observed by previous researchers using the InSAR and GPS method, but 3D deformation has not been measured yet due to low interferometric coherence. The combination of InSAR and MAI were applied to the ALOS PALSAR ascending and descending pairs, and were validated with the GPS in-situ measurements. The archived measurement accuracy was as little as 1.85, 5.49 and 3.08 cm in the east, north and up directions, respectively. This result indicates that the InSAR/MAI-derived 3D deformations are well matched with the GPS deformations. The 3D deformations are expected to allow us to improve estimation of the area affected by the 2010 Haiti earthquake.

The aims of this study were to assess the diagnostic value of the weight-to-height ratio (WHtR) for the detection of obesity and metabolic syndrome (MS) in Korean children and adolescents, and to determine the advantages of WHtR as a population-based screening tool in comparison with other obesity indicators, such as body mass index (BMI) and waist circumference (WC). We performed a cross-sectional analysis of data from 3057 children and adolescents (1625 boys, 1332 girls) aged 10–19 years who were included in the fifth Korean National Health and Nutrition Examination Survey (KNHANES, 2010–2012) up to the second year of the sixth KNHANES (2013–2014). Receiver operation characteristic (ROC) curves were generated to determine the optimal cutoff value and accuracy of WHtR for predicting individual obesity indicators or more than two non-WC components of MS. The area under the ROC curve (AUC) is a measure of the diagnostic power of a test. A perfect test will have an AUC of 1.0, and an AUC equal to 0.5 means that the test performs no better than chance. The optimal WHtR cutoff for the evaluation of general obesity and central obesity was 0.50 in boys and 0.47–0.48 in girls, and the AUC was 0.9. Regarding the assessment of each MS risk factor, the optimal WHtR cutoff was 0.43–0.50 in boys and 0.43–0.49 in girls, and these cutoffs were statistically significant only for the detection of high triglyceride and low High-density lipoprotein (HDL) cholesterol levels. When a pairwise comparison of the AUCs was conducted between WHtR and BMI/WC percentiles to quantify the differences in power for MS screening, the WHtR AUC values (boys, 0.691; girls, 0.684) were higher than those of other indices; however, these differences were not statistically significant (boys, p = 0.467; girls, p = 0.51). The WHtR cutoff value was 0.44 (sensitivity, 67.7%; specificity, 64.6%) for boys and 0.43 (sensitivity, 66.4%; specificity, 66.9%) for girls. There was no significant difference between the diagnostic power of WHtR and that of BMI/WC when screening for MS. Although the use of WHtR was not superior, WHtR is still useful as a screening tool for metabolic problems related to obesity because of its convenience.

Background : This study extends the findings of our previous examination of the relationship between obesity and depression in Korean adults. Here, we further investigate the relationships among body image perception, weight control method, and depression based on data from the Korea National Health and Nutrition Examination Survey in 2014 and 2016. Methods : In total, we analyzed 11,782 participants. We classified them into four groups according to body mass index (BMI): underweight (BMI 30.0 kg/m²). Current depression was defined as a score of at least 10 on the nine-item Patient Health Questionnaire. We performed chi-square tests and multivariate logistic regression analyses to examine the relationships among BMI, body image perception, method of weight control, and depression. Results : Depression was diagnosed in 6.5% of the study participants. The underweight group had the highest odds ratio (OR) for depression (OR, 1.94; 95% confidence interval [CI], 1.42–2.65). Further, participants in the extremely lean subgroup within the underweight group had an even higher OR for depression (OR, 3.06; 95% CI, 2.28–4.10). Regarding weight management methods, the rate of depression was higher for fasting and for skipping or reducing a meal than for exercise. Conclusion : Biased BMI and body image perception are associated with increased incidence of depression. In addition, specific weight control methods, such as fasting, skipping a meal, and reducing food consumption, are also associated with increased incidence of depression.

BackgroundWe developed for the first time a smartphone application designed for diabetes self-management in Korea and registered a patent for the relevant algorithm. We also investigated the user satisfaction with the application and the change in diabetes related self-care activities after using the application.MethodsWe conducted a questionnaire survey on volunteers with diabetes who were using the application. Ninety subjects responded to the questionnaire between June 2012 and March 2013. A modified version of the Summary of Diabetes Self-Care Activities (SDSCA) was used in this study.ResultsThe survey results exhibited a mean subject age of 44.0 years old, and males accounted for 78.9% of the subjects. Fifty percent of the subjects had diabetes for less than 3 years. The majority of respondents experienced positive changes in their clinical course after using the application (83.1%) and were satisfied with the structure and completeness of the application (86.7%). Additionally, the respondents' answers indicated that the application was easy to use (96.7%) and recommendable to others (97.7%) and that they would continue using the application to manage their diabetes (96.7%). After using the Diabetes Notepad application, diabetes related self-care activities assessed by SDSCA displayed statistically significant improvements (P

In this study, fungal strains designated as KNUF-22-14A and KNUF-22-15A were isolated from soil samples in Korea. These two strains were identified based on cultural and morphological characteristics as well as phylogenetic analyses and were found to be morphologically and phylogenetically identical. Upon their morphological comparison with closely related species, such as Tolypocladium album, T. amazonense, T. endophyticum, T. pustulatum, and T. tropicale, a difference in the size of short phialides [0.6-2.4(-9.3) 0.8-1.4 mm] was observed. Meanwhile, these strains had larger conidia (1.2-3.0 1.2-3.0 mm) than T. album, T. amazonense, T. endophyticum, and T. tropicale and smaller conidia than T. pustulatum. Phylogenetic analyses using a multi-locus datasets based on ITS, LSU, and SSU showed that KNUF-22-14A and KNUF-22-15A formed a distinct cluster from previously identified Tolypocladium species. Thus, these fungal strains isolated from soil in Korea are proposed as a novel species according to their characteristics and are named Tolypocladium globosum sp. nov. [ABSTRACT FROM AUTHOR]

Several environmental contaminants have been linked to the development of diabetes and increased diabetes‑associated mortality. Perfluorooctanoic acid (PFOA) is a widely used perfluoroalkane found in surfactants and lubricants, and in processing aids used in the production of polymers. Furthermore, PFOA has been detected in humans, wildlife and the environment. The present study investigated the toxic effects of PFOA on rat pancreatic β‑cell‑derived RIN‑m5F cells. Cell viability, apoptosis, reactive oxygen and nitrogen species, cytokine release and mitochondrial parameters, including membrane potential collapse, reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release were assessed. PFOA significantly decreased RIN‑m5F cell viability and increased apoptosis. Exposure to PFOA increased the formation of reactive oxygen species, mitochondrial superoxide, nitric oxide and proinflammatory cytokines. Furthermore, PFOA induced mitochondrial membrane potential collapse and reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release. These results indicate that PFOA is associated with the induction of apoptosis in RIN-m5F cells, and induces cytotoxicity via increased oxidative stress and mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

In this study, the support vector machine (SVM) was applied and validated by using the geographic information system (GIS) in order to map landslide susceptibility. In order to test the usefulness and effectiveness of the SVM, two study areas were carefully selected: the PyeongChang and Inje areas of Gangwon Province, Korea. This is because, not only did many landslides (2098 in PyeongChang and 2580 in Inje) occur in 2006 as a result of heavy rainfall, but the 2018Winter Olympics will be held in these areas. A variety of spatial data, including landslides, geology, topography, forest, soil, and land cover, were identified and collected in the study areas. Following this, the spatial data were compiled in a GIS-based database through the use of aerial photographs. Using this database, 18 factors relating to topography, geology, soil, forest and land use, were extracted and applied to the SVM. Next, the detected landslide data were randomly divided into two sets; one for training and the other for validation of the model. Furthermore, a SVM, specifically a type of data-mining classification model, was applied by using radial basis function kernels. Finally, the estimated landslide susceptibility maps were validated. In order to validate the maps, sensitivity analyses were carried out through area-under-the-curve analysis. The achieved accuracies from the SVM were approximately 81.36% and 77.49% in the PyeongChang and Inje areas, respectively. Moreover, a sensitivity assessment of the factors was performed. It was found that all of the factors, except for soil topography, soil drainage, soil material, soil texture, timber diameter, timber age, and timber density for the PyeongChang area, and timber diameter, timber age, and timber density for the Inje area, had relatively positive effects on the landslide susceptibility maps. These results indicate that SVMs can be useful and effective for landslide susceptibility analysis. [ABSTRACT FROM AUTHOR]