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Mass spectrometry methods exhibit higher accuracy and lower variability than immunoassays at low testosterone concentrations. We developed and validated an ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) assay for quantifying serum total testosterone.We used an ExionLC UPLC (Sciex, Framingham, MA, USA) system and a Sciex Triple Quad 6500+ (Sciex) MS/MS system in electrospray ionization and positive ion modes with multiple reaction monitoring transitions to evaluate precision, accuracy, linearity, lower limit of quantitation (LLOQ), carryover, ion suppression, stability, and reference intervals. For method comparison, we measured serum testosterone concentrations using this method in 40 subjects whose testosterone concentrations ranged from 0.14 to 55.48 nmol/L as determined using the Architect i2000 immunoassay (Abbott Diagnostics, Abbott Park, IL, USA) and in an additional 160 sera with testosterone concentrations1.67 nmol/L.The intra- and inter-run precision CVs were2.81%, and the accuracy bias values were3.85%, which were all acceptable. The verified linear interval was 0.03-180.84 nmol/L; the LLOQ was 0.03 nmol/L. No significant carryover and ion suppression were observed. The testosterone in serum was stable at 4°C, at -20°C, and after three freeze-thaw cycles. The reference intervals were successfully verified. The correlation was good at testosterone concentrations of 0.14-55.48 nmol/L; however, the Architect assay showed positive percent bias at concentrations1.67 nmol/L.The UPLC-MS/MS assay shows acceptable performance, with a lower LLOQ than the immunoassay. This method will enable the quantitation of low testosterone concentrations.

During a routine survey to establish a fungal inventory on broad-leaf deciduous trees in forests of the country, a black yeast-like species was repeatedly isolated from leaves of Acer pseudosieboldianum. Sequence comparisons using the ITS rDNA and LSU gene regions and morphological characteristics showed that the fungus isolated in this study was resided in a distinct lineage, indicating it as a novel species of Aureobasidium. This novel species is described here as Aureobasidium acericola sp. nov. The discovery of this fungus suggests that additional taxa residing in Aureobasidium are likely to be discovered in Korea and illustrates that further surveys and research should be planned to achieve this goal in the future

Trichoderma cornu-damae is known as a poisonous mushroom (Basidiomycota, Fungi) that produces several trichothecene mycotoxins. We constructed a chromosome-level genome assembly of T. cornu-damae with Hi-C sequencing data.

The birthrate in Japan is declining rapidly, which is attributed to the lack of perspective and consideration for “child-rearing” in the architecture of cities. Therefore, to gain knowledge of the ...

Several species of Gyromitra are highly poisonous when consumed raw the presence of gyromitrin. In this study, Gyromitra specimens deposited in the Korea National Arboretum were re-examined and subjected to molecular sequence analysis. G. gigas, G. aff. perlata, and G. tianshanensis were identified based on their morphological features and molecular phylogenetic analysis for the first time in Korea. Furthermore, internal transcribed spacer and 28S rRNA sequences of G. esculenta and G. infula were analyzed to confirm their phylogeny.

The Inocybaceae is a family of ectomycorrhizal fungi belonging to the Agaricales order. Most species in this family produce secondary metabolites, such as muscarine, psilocybin, and other compounds. In the present study, we conducted taxonomic studies on the Inocybaceae based on morphological and molecular phylogenetic analyses for the first time in Korea. As a result, seven species of Inocybaceae were newly recorded: Inocybe caroticolor, I. fuscidula, I. grammatoides, I. latibulosa, I. stellata, Inosperma shawarense, and Mallocybe malenconii. Among them, the genera Inosperma and Mallocybe were described for the first time in Korea. Relevant morphological characteristics, phylogenetic trees, and photographs are provided.

Auricularia (Auriculariaceae, Basidiomycota) is well-known jelly fungi, and most species are cultivated or utilized medicinally around the world. A total of 127 Auricularia specimens were collected during Korean mushroom forays by the Korea National Arboretum from 2008 to 2020. In this investigation, fungal barcode analysis and morphological examinations of 33 specimens were conducted and five Korean Auricularia species were identified. Of the species identified, A. americana, A. heimuer, and A. villosula were new to Korea, while A. auricula-judae which was previously identified in Korea, was not found. Herein, we discuss the Korean Auricularia species and provide a taxonomic key for their morphological identification.

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The complete mitochondrial genome of Colletotrichum siamense is characterized. The circular genome has a size of 52,710 bp, with a GC content of 34.45%, and contains 15 protein-coding genes, 23 tRNA genes, and 2 rRNA genes.

The severity of youth unemployment in South Korea has prompted the government to implement various preventive measures such as employment services and vocational training. Local governments implemented a Youth Job Seeker Allowance in 2016 as a new form of support, which was adopted by the central government in 2017. This study examines the impact of the Youth Job Seeker Allowance in South Korea on employment. It finds that the allowance had a positive effect on employment; recipients of the allowance have a higher probability of being employed. However, recipients took longer to obtain employment than non‐recipients, corroborating previous studies that unemployment benefits lengthen the duration of unemployment. But, recipients of the allowance have more time to look for quality work. Therefore, although the Youth Job Seeker Allowance has the effect of demotivating recipients from looking for employment, its limited duration of three months obliges them to engage in job search activities. The study has implications for the introduction of Youth Job Seeker Allowance systems to support job search activities.

To improve our understanding of the relationship between soil higher fungi (belonging to Ascomycota and Basidiomycota) and Abies koreana, we surveyed A. koreana soil fungal communities in a forest in Mt. Halla, Jeju Island, Korea by next-generation sequencing (Illumina Miseq). To confirm the soil higher fungal communities, we collected two types of soils from a defined plot: soils with dead (AKDTs) and living A. koreana (AKLTs), respectively. Soil fungi were classified into 2 phyla, 19 classes, 64 orders, 133 families, 195 genera, and 229 OTUs (895,705 sequence reads). Nonmetric multidimensional scaling (NMDS) showed significantly different soil higher fungal communities between AKDTs and AKLTs (p

Most macrofungi are cosmopolitan, occurring in both tropical and temperate regions. Studies on diversity and distribution of the mushroom flora in Korea are mainly conducted in major national parks and forest, but there are few studies on species distributed in urbanized areas. As part of the Korea National Arboretum project, we investigated the diversity of mushrooms through examining the distribution of mushrooms in Gyeongsang Province from May to September in 2017. In this province, we surveyed urbanized areas comprising three cultural heritage protection zones (Salix chaenomeloides forest, Tongdo Temple, Placenta Chamber of King Sejong's Princes), two urban parks (Duryu and Amnam parks), and 20 legally protected trees (such as Ginko biloba, Pinus densiflora, Quercus acutissima, Salix hallaisanensis, Zelkova serrata and so on). Consequently, 37 species on legally protected trees, 48 species in urban parks, and 84 species in cultural heritage protection zones were confirmed. A total of 37 families, 90 genera, and 139 species were identified. Of those, three species were confirmed for the first time in Korea. This study provides the basic data for the preparation of protection management protocols for macrofungal flora on legally protected trees and in cultural property protection areas.

During a survey of putative fungal pathogens infecting oak trees in the Gangwon Province of the Republic of Korea, a fungus resembling a Ceratocystis sp. was repeatedly isolated from natural wounds on Quercus variabilis. Morphological comparisons and DNA sequence comparisons based on partial β-tubulin and TEF-1α gene regions showed that the fungus resided in a distinct lineage. This novel Ceratocystis species is described here as C. quercicola sp. nov. This is the first novel species of Ceratocystis to be reported from Korea. A pathogenicity test showed that it can cause lesions on inoculated trees but that it had a very low level of aggressiveness. The discovery of this fungus suggests that additional taxa residing in Ceratocystis are likely to be discovered in Korea in the future.

Globally, almost 9.3% of the population aged 20–80 years have been diagnosed with diabetes making diabetes management a global health problem beyond specific regions or races. This study aimed to determine the effect of diabetes knowledge, self-stigma, and self-care behavior on the quality of life of patients with diabetes. This descriptive research study evaluated 180 patients receiving diabetes treatment at the outpatient Department of Endocrinology at C University Hospital. Data were collected between 30 July 2019, and 30 August 2019. The study variables were general patient characteristics, disease-related characteristics, quality of life, diabetes knowledge, self-stigma, and self-care behavior. Factors affecting the quality of life were analyzed by hierarchical regression. Self-stigma (β = −0.298), monthly income (β = 0.270), and self-care behavior (β = 0.140) significantly affected the quality of life, in that order. The higher the self-stigma, the lower the quality of life, and the higher the monthly income and the level of self-care behavior, the higher the quality of life. A psychosocial support program to positively change the attitude toward diabetes is needed to improve the quality of life among patients with diabetes.

Background The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) has substantially increased in clinical laboratories worldwide. To assess the status of clinical LC-MS/MS testing in Korean laboratories, a questionnaire survey was performed by the Clinical Mass Spectrometry Research Committee of the Korean Society of Clinical Chemistry. Methods The questionnaire was distributed to 19 clinical laboratories performing clinical LC-MS/MS from April to May 2018. It asked about general characteristics of the laboratory and commonly utilized clinical LC-MS/MS tests: newborn screening, tacrolimus test, vitamin D test, and plasma metanephrine test. Frequency analysis and other statistical analyses were performed. Results A total of 17 laboratories responded. The median number of LC-MS/MS instruments, laboratory medicine physicians, and technicians in each laboratory was three, one, and two, respectively. Nine laboratory directors had >10 years of experience with clinical LC-MS/MS. For each LC-MS/MS test, at least two concentrations of QC materials were measured every 24 hours during clinical testing, and all laboratories used QC acceptability criteria based on their established QC means and SDs. All laboratories participated in an external quality assessment program. However, there was inter-laboratory variability in sample preparation methods, instruments, reagents, internal standards, and calibrators. Conclusions LC-MS/MS has been successfully introduced in Korean clinical laboratories and is used within a quality framework. Further efforts for harmonization on a nationwide basis could facilitate the widespread use of LC-MS/MS.

The failure time of slope is essential for slope risk assessment. However, in previous studies, the safety factor and failure probability of slope have been regarded as the main research topic rather than the failure time. In this study, a stochastic failure distribution model related to the slope failure time is proposed. The stochastic failure distribution model based on fragility curves was used to analyze the failure process of shallow landslides under rainfall infiltration. The fragility curve is derived as a function of the intensity-duration of rainfall from the result of a probabilistic analysis, which considers the uncertainties of the hydraulic and mechanical properties of the soil. Then, the failure distribution analysis was performed for various rainfall conditions based on the generated fragility curves. Using the proposed failure distribution model, a chart showing the relationship between rainfall intensity and slope failure time was developed. The relationship is a kind of intensity-duration rainfall threshold for the initiation of shallow landslides. It is based on a probabilistic analysis considering the uncertainty of the soil properties. The proposed probabilistic failure distribution model could be beneficial for analyzing the failure process of hillslopes due to rainfall infiltration, and for predicting the time of landslide occurrence.

BACKGROUND Endoscopically or fluoroscopically guided dilation is a safe and effective alternative to surgery for patients with benign strictures of the gastric outlet. CASE SUMMARY We describe two cases where a novel approach with a Spyglass® choledochoscope in assessing the extent of benign duodenal strictures and aiding in placement of duodenal stents for treatment of the strictures. Choledochoscope-guided wire and stent placement was successful in all cases, leading to symptom resolution related to benign duodenal obstruction. No major adverse events were observed. CONCLUSION Choledochoscope-guided assessment and endoscopic therapy is a viable approach in relieving duodenal obstruction, if the conventional combined fluoroscopic and endoscopic methods fail.

This study explores determinants of middle-aged workers' participation in job training and provides implications to vitalizing middle-aged workers' participation in job training, using logistic regression analysis of Korea Labor Institute (KLIPS) data. As a result, among individual characteristics of older workers, residence in the metropolitan area, family relationship satisfaction, and household status have a significant effect on participation in job training. Regarding job and individual work characteristics, current work experience has a positive relationship. While for corporate characteristics, presence of unions and availability of statutory severance pay have a significant effect on participation in job training. Consequently, this study provides implications for vitalizing the older workers' participation in job training.

We retrospectively reviewed serum 25-hydroxy vitamin D (25(OH)D) test results from an adult Korean population visiting local clinics and hospitals between July 2017 and December 2021 to gather recent information on the prevalence of vitamin D deficiency. The prevalence of vitamin D deficiency status was investigated according to criteria offered by various clinical guidelines. During the study period, 180,289 subjects (29,658 men and 150,631 women) were tested for 25(OH)D. The overall prevalence rates of vitamin D deficiency status based on 25(OH)D level were as follows: 0.4% for

In this study, five YouTube Korean beauty creator channels that provide English subtitles are examined. These channels were selected based on the number of channel subscribers (popularity) and uploaded videos (sufficient content volume). The chapter presents and categorizes translation strategies that differ from existing audiovisual translation strategies. Although the subtitles of the YouTube videos do reflect conventional audiovisual translation strategies, especially the use of metaphorical expressions, new and different translation strategies are also present. These new translation strategies include: use of neologisms, phonetic transcription, frequent use of swear words and slang, intentional repetition of spelling, use of Internet terminology (chatting abbreviations/emojis/use of social media slang) and novel punctuation. Furthermore, new strategies appear to be related to other YouTube characteristics: multimodality; intertextuality; and heteroglossia.

Shallow slope failures occur almost every year during the rainy season. Continuous observation of the meteorological parameters and hydrological characteristics is required to more clearly understand the triggering mechanisms of shallow slope failure. In addition, influential factors, such as type of relative permeability models, air flow, and variation of hydraulic conductivity associated with stress–strain behavior of soil, have significant effects on the actual mechanism of rainfall infiltration. Real-time data including hourly rainfall and pore water pressure in response to rainfall was recorded by devices; then, the change in pore pressure from the devices was compared to the results from the infiltration analysis with applications of three relative permeability models, air flow, and the coupled hydro-mechanical analysis to examine an appropriate site-specific approach to a rainfall infiltration analysis. The infiltration and stability analyses based on the site-specific hydrologic characteristics were utilized to create maps of safety factors that depend on the cumulative rainfall. In regions vulnerable to landslides, rainfall forecast information and safety factor maps built by applying various rainfall scenarios can be useful in preparing countermeasures against disasters during the rainy season.