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Background and Objectives: Chronic hepatitis C (CHC) can be cured with direct-acting antiviral (DAA) therapy. In Korea, sofosbuvir (SOF) and ledipasvir (LDV)/SOF were launched in 2016. Patients who achieve a sustained virologic response (SVR) following DAA treatment are predicted to have a favorable prognosis. Nevertheless, little is known regarding the prognosis of Korean CHC patients who receive SOF-based treatment and achieve SVR. Therefore, the purpose of this study was to look into the long-term outcomes for these patients. Materials and Methods: This was a prospective, multicenter observational study. CHC patients were enrolled who, following SOF or LDV/SOF treatment, had achieved SVR. The last day for follow-up was December 2023. The primary endpoint was HCC occurrence, which was checked at least once per year. Results: A total of 516 patients were included in this analysis, with a median follow-up duration of 39.0 months. Among them, 231 were male patients (44.8%), with a median age of 62.0 years. Genotypes were 1 (90, 17.4%), 2 (423, 82.0%), and 3 (3, 0.6%). The combination of SOF plus ribavirin was the most common treatment (394, 76.4%). In total, 160 patients were cirrhotic (31.0%), and the mean Child–Pugh score was 5.1. Within a maximum of 7 years, 21 patients (4.1%) developed HCC. Patients with HCC were older (69 vs. 61 years, p = 0.013) and had a higher cirrhosis incidence (81.0 vs. 28.9%, p < 0.001), higher AFP (6.0 vs. 3.3, p = 0.003) and higher APRI (0.8 vs. 0.5, p = 0.005). Age over 65 (p = 0.016) and cirrhosis (p = 0.005) were found to be significant risk factors for HCC by Cox regression analysis. Conclusions: Patients who achieved SVR with SOF-based treatment had a relatively favorable prognosis. However, the risk of HCC was not eliminated, especially in older and cirrhotic patients. Therefore, routine follow-up, surveillance, and early treatment are required.

In South Korea, because of manpower and budgetary limitations, antimicrobial stewardship programs have relied on preauthorization. This study analyzed the impact of a prospective audit and feedback (PAF) program targeting inpatients undergoing intermittent hemodialysis or continuous renal replacement therapy, which was implemented at two community-based university hospitals. During three years of PAF, 27,906 antimicrobial prescriptions were reviewed, with 622 (2.2%) interventions. The mean incidence density per 1000 patient days of multidrug-resistant organisms, except for carbapenem-resistant Acinetobacter baumannii, decreased in the study population, whereas it increased among inpatients. Multivariable Poisson regression analysis revealed that after PAF, the incidences of vancomycin-resistant Enterococcus and mortality decreased (incidence risk ratio, 95% confidence interval: 0.53, 0.31–0.93 and 0.70, 0.55–0.90, respectively). Notably, after PAF, incorrect antimicrobial dosing rates significantly decreased (tau −0.244; p = 0.02). However, the incidences of other multidrug-resistant organisms, Clostridioides difficile, length of stay, and readmission did not significantly change. This study shows that in patients undergoing intermittent hemodialysis or continuous renal replacement, targeted PAF can significantly reduce multidrug-resistant organism rates and all-cause hospital mortality, despite limited resources. Furthermore, it can improve antimicrobial dosage accuracy.

Abstract The crystal structures of the pyribencarb E and Z stereoisomers were determined using single-crystal X-ray crystallography. The isomers were confirmed a single data respectively by crystal analysis, LC-UVD mass spectrometry, and NMR spectroscopy. Pyribencarb E crystallizes in triclinic P − 1 and the Z isomer in monoclinic P21/c, with the crystal structures showing comparable packing motifs. Moreover, molecular docking was carried out with cytochrome bc 1, revealing binding energies in the ranges of − 24.9 to − 17.6 and − 21.6 to − 14.7 kcal/mol for the E and Z isomers, respectively. Through a combined experimental and theoretical approach, this study contributes to our understanding of pesticides. Graphical Abstract

Abstract The effects of the grain size of Pt bottom electrodes on the ferroelectricity of hafnium zirconium oxide (HZO) were studied in terms of the orthorhombic phase transformation. HZO thin films were deposited by chemical solution deposition on the Pt bottom electrodes with various grain sizes which had been deposited by direct current sputtering. All the samples were crystallized by rapid thermal annealing at 700 °C to allow a phase transformation. The crystallographic phases were determined by grazing incidence X-ray diffraction, which showed that the bottom electrode with smaller Pt grains resulted in a larger orthorhombic phase composition in the HZO film. As a result, capacitors with smaller Pt grains for the bottom electrode showed greater ferroelectric polarization. The smaller grains produced larger in-plane stress which led to more orthorhombic phase transformation and higher ferroelectric polarization.

A new cultivar of oak mushroom Lentinula edodes ‘Jadam’ was bred from monokaryotic strains of ‘Hwadam-18’ and ‘GMLE36295-22’. The optimum temperature for mycelial growth of ‘Jadam’ on potato dextrose agar was 22-25℃. Total cultivation period of the new cultivar, from inoculation to its first harvest, was 122-124 days, shorter to that of the control cultivar ‘Hwadam’. Total yield of ‘Jadam’ was 623.8 g per 3 kg substrate, and is higher than that of ‘Hwadam’ (455.2 g). In the fruiting body of the new cultivar, the stipe was shorter and thinner than those of ‘Hwadam’. A farmhouse field test showed that the period of mycelial growth and browning was shorter than that of control cultivar ‘L808’. The total yield for 2 flush was 543.3 g for ‘Jadam’. It was similar to the 585.3 g of the control cultivar. Therefore, the new cultivar ‘Jadam’ could be a substitute for ‘L808’ in the field of farms.

Abstract From meteor radar observations typically measuring neutral winds and temperatures in the upper atmosphere, we showed that under‐dense meteor plasma trails respond to geomagnetic activity. Depending on the geomagnetic activity conditions, the parameters of the under‐dense trail echoes show substantial anomalies, and their responses are immediate. As geomagnetic activity increases, the decay time decreases up to about 10% at Kp = 8, while both the returned signal power and radial velocity error increase. In addition, the types of diffuse evolution vary with geomagnetic activity, resulting in strong geomagnetic activity that immediately affects the trail. The evolution of the trail is affected not only by the ambient mesospheric neutral atmospheric properties but also by electromagnetic effects, such as strong electric fields inside meteor trails. Furthermore, our findings suggest that the geomagnetic effect should be considered when estimating atmospheric parameters from MR during a geomagnetically active period.

BackgroundPsychological status affects dietary intake, and recognizing genetic information can lead to behavior changes by influencing psychological factors such as anxiety or depression.ObjectivesIn this study, we examined the effects of disclosing genetic information on anxiety or depression levels and the association between these psychological factors and dietary intake.MethodsA total of 100 healthy adults were randomly assigned to an intervention group (n = 65) informed about their genetic test results regarding body mass index and lipid profiles (triglyceride and cholesterol concentrations) and a not-informed control group (CON, n = 35). Based on polygenic risk scores, participants in the intervention group were subclassified into an intervention-low risk (ILR, n = 32) and an intervention-high risk (IHR, n = 33) group. Nutrient and food intakes were assessed via a 3-day dietary record at baseline and at 3 and 6 months. Depression and anxiety levels were measured using PHQ-9 and GAD-7 questionnaires, and the relative levels of blood metabolites were measure using GC-MS/MS analysis.ResultsNoticeable changes in dietary intake as well as psychological factors were observed in male subjects, with those perceiving their genetic risks as low (ILR) showing a significant increase in protein intake at 3 months compared to baseline (ILR: 3.9 ± 1.4, pConclusionsTaken together, anxiety levels were decreased in male subjects who perceived their genetic risk to be low, and the decrease in anxiety levels was associated with an increase in meat intake. This suggests that recognizing genetic information may affect psychological factors and dietary intake.

표고 ‘화담’의 톱밥배지 안정생산을 위해 침공처리가 균사배양 및 자실체 생산성에 미치는 영향을 조사하였다. 종균 접종후 배지 온도는 배양 23일에 27.0-28.8℃, CO2농도는 배양 16일에 14.0-15.6%까지 높아진 후 감소하였고, O2농도는 CO2농도와 반대의 경향이었다. 배양기간중 침공횟수가 많을수록 배지의 명도(L값)는 감소하고, 색차(ΔE)와 중량감모율은 증가하였다. 침공처리에 따른 1주기 재배기간은 큰 차이를 보이지 않았지만, 침공처리 횟수가 늘어날수록 자실체 발이수가 증가하여 3회 침공처리구의 3주기 총수량이 605.7 g으로 가장 우수하였다.

Dermal & inhalation exposure was examined and according to these results, risk assessment of agricultural workers to thiamethoxam was performed during pesticide mixing/loading and hand-held sprayer application (11 replicates, each of about 1000 L of spray suspension) in vineyards. For the whole body dosimetry (WBD), clothing (Outer and inner), gauze, and nitrile gloves were analyzed to determine dermal exposure using whole-body dosimetry exposure protocol. The inhalation exposure was measured using a glass fiber filter with an IOM sampler. Analytical method validation of exposure matrices was evaluated including the field recovery and breakthrough test. The dermal exposure amount during mixing/loading was 0.163 mg (0.0004% of the total mixed/loaded active ingredient [a.i.]), whereas there was no inhalation exposure. The gloves (0.154 mg, 94.5%) were the most exposed body parts followed by the chest and stomach (0.009 mg, 5.5%). During application, the dermal and inhalation exposure amounts were 32.3 mg (0.07% of the total applied a.i.) and 10.8 µg (2.4 × 10−6% of the total applied a.i), respectively. The shin (35.1%) had the highest exposure to pesticides, followed by the chest & stomach (15.6%) and pelvis (12.6%). In case of mixing/loading, the amounts of actual dermal exposure (ADE) and actual inhalation exposure (AIE) were 0.0 and 0.0 μg/day, while those of ADE and AIE were 4707.6 and 15.8 μg/day for application. In risk assessment of the two different scenarios, the risk index was much lower than 1 (mixing/loading:0.000, application:0.014), indicating that vineyard workers are at low risk of thiamethoxam exposure. To determine the validity of the risk assessment using WBD method, the urinary metabolite was analyzed. Comparison of biomonitoring data and WBD exposure data show a reliable correlation (r = 0.885, p = 0.0003), suggesting that these are suitable methods to estimate exposure.

Aim and Objectives: Direct-acting antiviral (DAA) therapy can cure chronic hepatitis C (CHC), and daclatasvir (DCV)/asunaprevir (ASV) was the first interferon-free DAA therapy introduced in Korea. Patients who achieve sustained virologic response (SVR) after DAA treatment are expected to have good prognoses. Therefore, in this study, we aimed to investigate the prognosis of these patients. Materials and Methods: This multicenter prospective observational study included patients with CHC who achieved SVR after DCV/ASV treatment. The primary endpoint was hepatocellular carcinoma (HCC) occurrence, which was reviewed annually. Results: We included 302 patients (median follow-up duration: 38 [16.5–60.0] months; median age: 58 [49–67] years) in the study. Cirrhosis was observed in 103 patients (34.1%), and the median Child–Pugh score was 5.0. HCC occurred in 16 patients (5.3%) within six years post-SVR; these patients were older and had higher cirrhosis prevalence, alpha-fetoprotein levels, and fibrosis-4 index scores than did those without HCC development. Cox proportional hazards analysis revealed that age > 71 years (p = 0.005) and cirrhosis (p = 0.035) were significant risk factors for HCC occurrence. Conclusions: Although the prognoses of patients who achieved SVR with DCV/ASV therapy were generally good, the risk for HCC was present, especially in older patients and in those with cirrhosis. Hence, early treatment at younger ages and regular follow-up surveillance after achieving SVR are warranted.

Abstract The objective of the study was to develop and validate a prediction model that identifies COVID-19 patients at risk of requiring oxygen support based on five parameters: C-reactive protein (CRP), hypertension, age, and neutrophil and lymphocyte counts (CHANeL). This retrospective cohort study included 221 consecutive COVID-19 patients and the patients were randomly assigned randomly to a training set and a test set in a ratio of 1:1. Logistic regression, logistic LASSO regression, Random Forest, Support Vector Machine, and XGBoost analyses were performed based on age, hypertension status, serial CRP, and neutrophil and lymphocyte counts during the first 3 days of hospitalization. The ability of the model to predict oxygen requirement during hospitalization was tested. During hospitalization, 45 (41.8%) patients in the training set (n = 110) and 41 (36.9%) in the test set (n = 111) required supplementary oxygen support. The logistic LASSO regression model exhibited the highest AUC for the test set, with a sensitivity of 0.927 and a specificity of 0.814. An online risk calculator for oxygen requirement using CHANeL predictors was developed. “CHANeL” prediction models based on serial CRP, neutrophil, and lymphocyte counts during the first 3 days of hospitalization, along with age and hypertension status, provide a reliable estimate of the risk of supplement oxygen requirement among patients hospitalized with COVID-19.

Abstract The objective of the study was to identify distinct patterns in inflammatory immune responses of COVID-19 patients and to investigate their association with clinical course and outcome. Data from hospitalized COVID-19 patients were retrieved from electronic medical record. Supervised k-means clustering of serial C-reactive protein levels (CRP), absolute neutrophil counts (ANC), and absolute lymphocyte counts (ALC) was used to assign immune responses to one of three groups. Then, relationships between patterns of inflammatory responses and clinical course and outcome of COVID-19 were assessed in a discovery and validation cohort. Unbiased clustering analysis grouped 105 patients of a discovery cohort into three distinct clusters. Cluster 1 (hyper-inflammatory immune response) was characterized by high CRP levels, high ANC, and low ALC, whereas Cluster 3 (hypo-inflammatory immune response) was associated with low CRP levels and normal ANC and ALC. Cluster 2 showed an intermediate pattern. All patients in Cluster 1 required oxygen support whilst 61% patients in Cluster 2 and no patient in Cluster 3 required supplementary oxygen. Two (13.3%) patients in Cluster 1 died, whereas no patient in Clusters 2 and 3 died. The results were confirmed in an independent validation cohort of 116 patients. We identified three different patterns of inflammatory immune response to COVID-19. Hyper-inflammatory immune responses with elevated CRP, neutrophilia, and lymphopenia are associated with a severe disease and a worse outcome. Therefore, targeting the hyper-inflammatory response might improve the clinical outcome of COVID-19.

Background and Objectives: The Child–Pugh (CP) score and Model for End-Stage Liver Disease (MELD) are classical systems for predicting mortality in patients with liver cirrhosis (LC). The MELD-GFR assessment in liver disease–sodium (MELD-GRAIL-Na) was designed to better reflect renal function and, therefore, provide better mortality predictions. This study aimed to compare the prediction accuracy of MELD-GRAIL-Na compared to CP and MELD in predicting short-term (1- and 3-month) mortality in Korean patients. Materials and Methods: Medical records of patients with LC admitted to the Konkuk University Hospital from 2015 to 2020 were retrospectively reviewed. Predictive values of the CP, MELD, and MELD-GRAIL-Na for 1-month and 3-month mortality were calculated using the area under the receiver operating curve (AUROC) and were compared using DeLong’s test. Results: In total, 1249 patients were enrolled; 102 died within 1 month, and 146 within 3 months. AUROCs of CP, MELD, and MELD-GRAIL-Na were 0.831, 0.847, and 0.857 for 1-month mortality and 0.837, 0.827, and 0.835 for 3-month mortality, respectively, indicating no statistical significance. For patients with CP classes B and C, AUROCs of CP, MELD, and MELD-GRAIL-Na were 0.782, 0.809, and 0.825 for 1-month mortality and 0.775, 0.769, and 0.786 for 3-month mortality, respectively. There was a significant difference between CP and MELD-GRAIL-Na in predicting 1-month mortality (p = 0.0428) and between MELD and MELD-GRAIL-Na in predicting 1-month (p = 0.0493) and 3-month mortality (p = 0.0225). Conclusions: Compared to CP and MELD, MELD-GRAIL-Na was found to be a better and more useful system for evaluating short-term (1- and 3-month) mortality in Korean patients with cirrhosis, especially those with advanced cirrhosis (CP class B and C).

To replace the sawdust in the growth medium of oyster mushroom to utilize its by-product spent mushroom substrates (SMS) as feed for ruminant, we performed cultivation test using cotton seed hull pellet (CSHP), corn stalk pellet (CSP), corncob (CC), and analyzed the feed chemical properties of those SMS. As a result of cultivation test, CC and CSHP treatment took 27 days for spawn run, 4 days for primordium formation, and 3 days for development fruiting bodies, resulting in a total cultivation period of 34 days. The yield per bottle was 134 g for CC treatment, similar to 130 g for control, while CSHP treatment (112 g) and CSP treatment (68 g) were lower than that of control. The highest biological efficiency (BE) was shown in CC treatment as 80.1%, which was 11.4% higher than 68.7% of control. The SMS of CC treatment had a relatively low content of neutral detergent fiber and acid detergent fiber, and in particular, lignin content was the lowest and crude protein content was the highest among other treatments. Therefore, CC as a substitute material for sawdust was capable of stable mushroom production and excellent nutritional value as a feed for its by-products.

This study was carried out to develop a new method of cultivation of ‘Hwadam’ a new variety of Lentinula edodes, to improve fruiting body productivity and reduce labor. To determine the optimum filter number for box cultivation, L. edodes were assessed for their cultural characteristics and mushroom yield. During spawn running of L. edodes in the box, the temperature gradually increased to the highest value of 25.8℃, 23.7℃, and 23.0℃ on day 18 for the four filter, two filter, and no treatment groups, respectively. Oxygen concentration displayed an opposite trend to carbon dioxide concentration, reaching the lowest value on day 21. The oxygen concentration progressively increased as more filters were used (5.4%, 8.2%, and 8.9% treatment with no, two, and four filters, respectively. Growth of L, edodes in the box resulted in the highest yield (2,228 g/7kg substrate) and biological efficiency (70.7%) using four filters. The biological efficiency of the four filter treatment was 29.4% higher compared to bag cultivation (41.3%). Further studies are necessary to verify stable productivity of fruiting bodies through repeated cultivation.

A new oak mushroom cultivar ‘Hwadam’ was bred from monokaryotic strains of ‘GMLE36062’ and ‘LE15401’. The optimum temperature for mycelial growth of ‘Hwadam’ on potato dextrose agar was 25℃. The cultivation period of ‘Hwadam’ lasted for 129 days until the first harvest of the fruiting bodies, including 35 days for spawn run, 84 days for browning, and 10 days for development of fruiting bodies. The fruiting bodies of ‘Hwadam’ had a hemispherical, brighter pileus and thicker stipe than the control cultivar (Sanjo 701ho). The three-cycle yield of ‘Hwadam’ was 554 g, which was higher than that of control cultivar (405 g). In addition, ‘Hwadam’ contained 79.4 mg/g of beta-glucan and 0.93 mg GAEs/g of phenolic compounds, which was similar to that of the control cultivar but higher than that of 'L808' and 'Chujae 2ho'.

The Thoeris defense system is a recently discovered bacterial defense system that protects bacteria against phage infection and consists of the two genes thsA and thsB. Here, the authors present the crystal structures of Bacillus cereus ThsA and ThsB and show that ThsA is a NAD+ cleaving enzyme.

Abstract Background Vitamin D deficiency has been often observed in obese persons. One of the mechanisms suggested for low vitamin D status in obesity was decreased bioavailability of vitamin D (VD) due to sequestration in adipose tissue. However, only few studies have investigated this mechanism via quantifying vitamin D levels from tissues from the obese. Methods Six-wk-old C57BL/6 mice were fed 10 or 45% kcal fat (CON or HFD) diets containing 50, 1000 or 25,000 IU vitamin D3/kg diet (LVd, CVd or HVd) for 13 wks. Serum 25-hydroxyvitamin D (25(OH)D) levels were determined by radioimmunoassay and liver and adipose tissue cholecalciferol (VD3) and 25-hydrocholecalciferol (25(OH)D3) levels were measured by LC-MS/MS. mRNA levels of jejunal Mttp, Cd36, Sr-b1, Npc1l1, and Abca1 and liver and adipose tissue 25-hydroxylases (Cyp2r1 and Cyp27a1) were determined by real-time PCR. Results Serum 25(OH)D levels were affected by dietary vitamin D content but differential effects were observed between HFD and CON groups. When vitamin D intake was at a supplementary level, the HFD-HVd group had lower serum 25(OH)D levels than the CON-HVd group, while there was no significant difference between the HFD and CON groups fed LVd or CVd. Total amount of VD3 in liver and adipose tissue were significantly higher in HFD-HVd group compared with the CON-HVd group. However, no difference in total amount of tissue VD3 was observed between the CON and HFD groups fed CVd. In jejunum, mRNA levels of Mttp and Abca1 were significantly higher in HFD groups than CON groups. There was no difference in mRNA levels of liver 25-hydroxylases by both dietary fat amount and vitamin D content. Conclusion A significant amount of VD3 seemed to be stored in the liver and adipose tissue when dietary vitamin D is at a supplementation level; thus excess body adiposity could contribute to relatively low serum 25(OH)D level when vitamin D was supplemented.

Korea Polar Research Institute (KOPRI) installed an ionospheric sounding radar system called Vertical Incidence Pulsed Ionospheric Radar (VIPIR) at Jang Bogo Station (JBS) in 2015 in order to routinely monitor the state of the ionosphere in the auroral oval and polar cap regions. Since 2017, after two-year test operation, it has been continuously operated to produce various ionospheric parameters. In this article, we will introduce the characteristics of the JBS-VIPIR observations and possible applications of the data for the study on the polar ionosphere. The JBS-VIPIR utilizes a log periodic transmit antenna that transmits 0.5–25 MHz radio waves, and a receiving array of 8 dipole antennas. It is operated in the Dynasonde B-mode pulse scheme and utilizes the 3-D inversion program, called NeXtYZ, for the data acquisition and processing, instead of the conventional 1-D inversion procedure as used in the most of digisonde observations. The JBS-VIPIR outputs include the height profiles of the electron density, ionospheric tilts, and ion drifts with a 2-minute temporal resolution in the bottomside ionosphere. With these observations, possible research applications will be briefly described in combination with other observations for the aurora, the neutral atmosphere and the magnetosphere simultaneously conducted at JBS.

This study was performed to develop a useful method for substrate pH adjustment in bottle cultivation of Grifola frondosa. Four types of organic acid solution—citric acid, malic acid, tartaric acid, and succinic acid—were added at 0.5% to 3.0% (w/v) into the substrate. The pH after the organic acid treatments ranged from 3.8 to 4.8 for the mycelial growth of G. frondosa after sterilization. Supplementation with succinic acid at 0.5% resulted in a shorter cultivation period and higher consistent yields compared to other organic acid treatments. These results indicate that the technique we developed is beneficial for higher production of G. frondosa using bottle cultivation.

Abstract Background Severe fever with thrombocytopenia syndrome (SFTS) is emerging in Asian 3 countries, China, Japan and Korea, which are scrub typhus endemic areas, and its incidence is increasing. As the two infections overlap epidemiologically and clinically and the accessibility or sensitivity of diagnostic tests is limited, early clinical prediction may be useful for diagnostic and therapeutic purposes. Methods Patients aged ≥16 years who were clinically suspected and laboratory-confirmed to be infected with Orientia tsutsugamushi or the SFTS virus in South Korea were enrolled. Clinical and laboratory parameters were compared. Scrub typhus was further subclassified according to the status of eschar and skin rash. An SFTS prediction scoring tool was generated based on a logistic regression analysis of SFTS compared with scrub typhus. Results The analysis was performed on 255 patients with scrub typhus and 107 patients with SFTS. At initial presentation, subjective symptoms except for gastrointestinal symptoms, were more prominent in scrub typhus patients. In addition to the characteristic eschar and skin rash, headache was significantly more prominent in scrub typhus, while laboratory abnormalities were more prominent in SFTS. Leukopenia (white blood cell count

Vertical incidence pulsed ionospheric radar (VIPIR) has been operated to observe the polar ionosphere with Dynasonde analysis software at Jang Bogo Station (JBS), Antarctica, since 2017. The JBS-VIPIR-Dynasonde (JVD) provides ionospheric parameters such as the height profile of electron density with NmF2 and hmF2, the ion drift, and the ionospheric tilt in the bottomside ionosphere. The JBS (74.6°S, 164.2°E) is located in the polar cap, cusp, or auroral region depending on the geomagnetic activity and local time. In the present study, an initial assessment of JVD ionospheric densities is attempted by the comparison with GPS TEC measurements which are simultaneously obtained from the GPS receiver at JBS during the solar minimum period from 2017 to 2019. It is found that the JVD NmF2 and bottomside TEC (bTEC) show a generally good correlation with GPS TEC for geomagnetically quiet conditions. However, the bTEC seems to be less correlated with the GPS TEC with slightly larger spreads especially during the daytime and in summer, which seems to be associated with the characteristics of the polar ionosphere such as energetic particle precipitations and large density irregularities. It is also found that the Dynasonde analysis seems to show some limitations to handle these characteristics of the polar ionosphere and needs to be improved to produce more accurate ionospheric density profiles especially during disturbed conditions.

BACKGROUND:The prolonged manifestation of concurrent leukopenia, thrombocytopenia and normal C-reactive protein (CRP) (named as SFTS prediction score) in febrile diseases is not usual and may be used to make an initial differential diagnosis, which is a characteristic finding of severe fever with thrombocytopenia syndrome (SFTS). METHODS:The dynamics of SFTS prediction scores was investigated in SFTS patients. The study subjects for the comparison were febrile patients aged ≥ 16 years with SFTS scores of 2 (S2) or 3 (S3) who visited an emergency room for a 4-year study period. The dynamic distribution of S2 and S3 at presentation with regards to onset of illness, the characteristics of responsible diseases and the predictability of SFTS in both groups were described. RESULTS:In 104 patients with SFTS, the daily proportion of S2 or S3 ranged from 58.3 to 100% from day (D) 1 to D12 after the onset of illness. The S2 subtype of 'leukopenia plus thrombocytopenia' and S3 represented 72.7-100% of all scores. In contrast, for the 130 patients in the febrile cohort, 73.8% of evaluations were distributed between D1 and D4 after the onset of illness, and 68.8% of patients had the S2 subtype of 'leukopenia plus normal CRP'. Upper respiratory infection was the most frequent (50.0%) cause of diseases. Pneumonia (13.8%) and urosepsis (6.2%) initially presented with either S2 with normal CRP or S3 but had poor prognosis. The presence of S2 or S3 predicted SFTS with sensitivity and specificity of 0.85 (0.42-0.99; 95% CI) and 0.98 (0.98-0.98; 95% CI), respectively. CONCLUSION:The temporal distribution and composition of S2 or S3 were unique in several febrile diseases including SFTS, and the SFTS prediction score may be useful for differentiating febrile diseases in primary care settings of SFTS endemic areas.

Jang Bogo Station (JBS), the second Korean Antarctic research station, was established in Terra Nova Bay, Antarctica (74.62°S 164.22°E) in February 2014 in order to expand the Korea Polar Research Institute (KOPRI) research capabilities. One of the main research areas at JBS is space environmental research. The goal of the research is to better understand the general characteristics of the polar region ionosphere and thermosphere and their responses to solar wind and the magnetosphere. Ground-based observations at JBS for upper atmospheric wind and temperature measurements using the Fabry-Perot Interferometer (FPI) began in March 2014. Ionospheric radar (VIPIR) measurements have been collected since 2015 to monitor the state of the polar ionosphere for electron density height profiles, horizontal density gradients, and ion drifts. To investigate the magnetosphere and geomagnetic field variations, a search-coil magnetometer and vector magnetometer were installed in 2017 and 2018, respectively. Since JBS is positioned in an ideal location for auroral observations, we installed an auroral all-sky imager with a color sensor in January 2018 to study substorms as well as auroras. In addition to these observations, we are also operating a proton auroral imager, airglow imager, global positioning system total electron content (GPS TEC)/scintillation monitor, and neutron monitor in collaboration with other institutes. In this article, we briefly introduce the observational activities performed at JBS and the preliminary results of these observations.

Abstract Background Tuberculosis (TB), especially extrapulmonary tuberculosis (EPTB), is an important cause of fever of unknown origin (FUO) in TB-burdened areas. Little information is known about patients with EPTB with clinical features presenting as FUO and about the factor of delaying the diagnosis. Methods We retrospectively analyzed EPTB patients who were referred with FUO at 3 university-affiliated hospitals over 8 years (2010–2017). The subjects were assigned to groups of early diagnosis and delayed diagnosis within 3 days of an initial comprehensive evaluation from the referral. Clinical and laboratory variables were compared between the groups. Results A total of 95 patients with febrile EPTB were included. Localizing symptoms and/or signs suggestive of anatomy were identified in 62.1% of the patients. Concurrent lung involvement by TB was presented by 49.5% (47/95) of the patients, and only 23.4% of them showed typical findings of pulmonary TB on simple chest X-ray. Most of the patients showed abnormal lesions on cross-sectional CT (98.9%) and MRI (100%). The clinical variables and blood test results of patients were not significantly different between the two groups. The less typical imaging finding of EPTB on CT (38.5% vs. 79.0%) and MRI (37.5% vs. 79.0%) in the delayed diagnosis group was a risk factor for delayed diagnosis. Conclusion Febrile EPTB referred as FUO showed nonspecific clinical manifestations. The active application of cross-sectional imaging tests according to clinical clues or randomly in the absence of local manifestations, combined with invasive diagnostic approaches even for atypical presentations may lead to an earlier diagnosis of febrile EPTB.

As a part of collaborative efforts to understand ionospheric irregularities, the Korea ionospheric scintillation sites (KISS) network has been built based on global positioning system (GPS) receivers with sampling rates higher than 1 Hz. We produce the rate of TEC index (ROTI) to represent GPS TEC fluctuations related to ionospheric irregularities. In the KISS network, two ground-based GPS sites at Kiruna (marker: KIRN; geographic: 67.9° N, 21.4° E; geomagnetic: 65.2° N) and Chuuk (marker: CHUK; geographic: 7.5° N, 151.9° E; geomagnetic: 0.4° N) were selected to evaluate the ROTI value for ionospheric irregularities during the occurrence of the 2015 St. Patrick’s Day storm. The KIRN ROTI values in the aurora region appear to be generally much higher than the CHUK ROTI values in the EIA region. The CHUK ROTI values increased to ~0.5 TECU/min around UT=13:00 (LT=23:00) on March 16 in the quiet geomagnetic condition. On March 17, 2015, CHUK ROTI values more than 1.0 TECU/min were measured between UT=9:00 and 12:00 (LT=19:00 and 22:00) during the first main phase of the St. Patrick’s Day storm. This may be due to ionospheric irregularities by increased pre-reversal enhancement (PRE) after sunset during the geomagnetic storm. Post-midnight, the CHUK ROTI showed two peaks of ~0.5 TECU/min and ~0.3 TECU/min near UT=15:00 (LT=01:00) and UT=18:00 (LT=04:00) at the second main phase. The KIRN site showed significant peaks of ROTI around geomagnetic latitude=63.3° N and MLT=15:40 on the same day. These can be explained by enhanced ionospheric irregularities in the auroral oval at the maximum of AE index

In December 2015, we have installed neutron monitors at the Jang Bogo station in Antarctica. The Jang Bogo station is the second science station which is located at the coast (74° 37.4´S, 164° 13.7´E) of Terra Nova Bay in Northern Victoria Land of Antarctica. A neutron monitor is an instrument to detect neutrons from secondary cosmic rays collided by the atmosphere. The installation of neutron monitor at Jang Bogo station is a part of transferred mission for neutron monitor at McMurdo station of USA. Among 18 tubes of 18-NM64 neutron monitor, we have completed relocation of 6 tubes and the rest will be transferred in December 2017. Currently, comparison of data from the neutron monitors of both two stations is under way and there is a good agreement between the data. The neutron monitors at Jang Bogo station will be quite useful to study the space weather when the installation is completed.

The objective of this study is to develop a comprehensive and simple method for the simultaneous determination of anthelmintic and antiprotozoal drug residues in fish. For sample preparation, we used the “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) method with a simple modification. The sample was extracted with water and 1% formic acid in acetonitrile/methanol (MeCN/MeOH) (95:5, v/v), followed by phase separation (salting out) with MgSO4 and NaCl (4:1, w/w). After centrifugation, an aliquot of the extract was purified by dispersive solid-phase extraction (d-SPE) prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The method was validated at three concentration levels for all matrices, in accordance with the Codex guidelines (CAC/GL-71). Quantitative analysis was performed using the method of matrix-matched calibration. The recoveries were between 60.6% and 119.9%, with coefficients of variation (CV) −1 to 4.8 μg kg−1 for all matrices. This comprehensive method can be used for the investigation of both anthelmintic and antiprotozoal drugs belonging to different chemical families in fishery products.

Tenebrio molitor larvae (mealworm) is an edible insect and is considered a future food. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a novel method for simultaneous analysis of 353 target analytes was developed and validated. Various sample preparation steps including “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) extraction conditions, number of acetonitrile-hexane partitions, and dispersive-solid phase extraction (dSPE) sorbents were compared, and the optimal conditions were determined. In the established method, 5 g of homogenized mealworms was extracted with acetonitrile and treated with QuEChERS EN 15662 salts. The crude extract was subjected to three rounds of acetonitrile-hexane partitioning, and the acetonitrile layer was cleaned with C18 dSPE. The final solution was matrix-matched and injected into LC-MS/MS (2 μL). For target analytes, the limits of quantitation (LOQs) were ≤10 μg/kg, and the correlation coefficient (r2) of calibration was >0.990. In recovery tests, more than 90% of the pesticides showed an excellent recovery range (70–120%) with relative standard deviation (RSD) ≤20%. For more than 94% of pesticides, a negligible matrix effect (within ±20%) was observed. The analytical method was successfully applied and used for the detection of three urea pesticides in 4 of 11 mealworm samples.

Background/Aims: Tumor recurrence after curative therapy is common for patients with hepatocellular carcinoma (HCC). As fibrosis and chronic inflammation contribute to the progression of HCC, we aimed to identify the predictive value of inflammatory and fibrosis markers for HCC recurrence after curative therapy using radiofrequency ablation (RFA). Materials and Methods: We retrospectively reviewed the records of patients with HCC treated with RFA between October 2005 and September 2013. The median duration of follow-up was 40 months (4-95 months). Inflammatory and fibrosis markers and demographic and clinical data were analyzed by Cox proportional hazards model using univariate and multivariate analyses and longitudinal analysis. Results: A total of 98 patients were included for analysis. There were 54 cases of HCC recurrence (55.1%). The aspartate aminotransferase-to-platelet ratio index (APRI; 2.3 ± 1.8 vs. 1.3 ± 1.4, P = 0.018) was significantly higher in the recurrence group than in the recurrence-free group. In multivariate analysis, APRI (hazard ratio, 2.64; confidence interval, 1.488-4.714; P = 0.001) was an independent risk factor for tumor recurrence. In particular, patients with APRI >1.38 showed a higher recurrence rate than patients with APRI ≤1.38 (P < 0.001). Longitudinal analysis showed persistently higher APRI values when assessed 12 months after RFA in patients who developed recurrence during follow-up than those who remained recurrence-free. Conclusions: These findings show that a high APRI value is associated with HCC recurrence after RFA. Therefore, APRI could play an important role in predicting HCC recurrence after RFA.

A simultaneous analytical method for the organophosphorus insecticide fenthion and its five metabolites (fenthion oxon, fenthion oxon sulfoxide, fenthion oxon sulfone, fenthion sulfoxide, and fenthion sulfone) was developed based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Five matrices (brown rice, chili pepper, orange, potato, and soybean) were selected to validate the method. The target compounds were analyzed using positive electrospray ionization in the multiple reaction monitoring mode. For the best sensitivity in regard to the detector response, water and methanol containing formic acid (0.1%) were selected as the mobile phase. The optimum extraction efficiency was obtained through a citrate-buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. Recovery tests were carried out at three spiking levels (n = 3). At all fortification levels, the accuracy and precision results were between 70% and 120% with a relative standard deviation of ≤15%. The limit of quantitation was 0.01 mg/kg, and the correlation coefficients (r2) of the matrix-matched calibration curves were >0.99. Significant signal suppression in the detector responses were observed for all matrices, suggesting that a compensation method, such as matrix-matched calibration, is required to provide accurate quantitative results. The applicability of the presented method was confirmed for the simultaneous analysis of fenthion and its metabolites in various crops.

Background: White ginseng (Panax ginseng Meyer) is commonly distributed as a health food in food markets. However, there is no practical method for distinguishing Korean white ginseng (KWG) from Chinese white ginseng (CWG), except for relying on the traceability system in the market. Methods: Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with orthogonal partial least squares discrimination analysis (OPLS-DA) was employed to discriminate between KWG and CWG. Results: The origins of white ginsengs in two test sets (1.0 μL and 0.2 μL injections) could be successfully discriminated by the OPLS-DA analysis. From OPLS-DA S-plots, KWG exhibited tentative markers derived from ginsenoside Rf and notoginsenoside R3 isomer, whereas CWG exhibited tentative markers derived from ginsenoside Ro and chikusetsusaponin Iva. Conclusion: Results suggest that ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry coupled with OPLS-DA is an efficient tool for identifying the difference between the geographical origins of white ginsengs.

Since the operation of the King Sejong Station (KSS) started in Antarctic Peninsula in 1989, there have been continuous efforts to perform the observation for the upper atmosphere. The observations during the initial period of the station include Fabry-Perot Interferometer (FPI) and Michelson Interferometer for the mesosphere and thermosphere, which are no longer in operation. In 2002, in collaboration with York University, Canada, the Spectral Airglow Temperature Imager (SATI) was installed to observe the temperature in the mesosphere and lower thermosphere (MLT) region and it has still been producing the mesopause temperature data until present. The observation was extended by installing the meteor radar in 2007 to observe the neutral winds and temperature in the MLT region during the day and night in collaboration with Chungnam National University. We also installed the all sky camera in 2008 to observe the wave structures in the MLT region. All these observations are utilized to study on the physical characteristics of the MLT region and also on the wave phenomena such as the tide and gravity wave in the upper atmosphere over KSS that is well known for the strong gravity wave activity. In this article, brief introductions for the currently operating instruments at KSS will be presented with their applications for the study of the upper atmosphere.

Discriminating between two herbal medicines (Panax ginseng and Panax quinquefolius), with similar chemical and physical properties but different therapeutic effects, is a very serious and difficult problem. Differentiation between two processed ginseng genera is even more difficult because the characteristics of their appearance are very similar. An ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS)-based metabolomic technique was applied for the metabolite profiling of 40 processed P. ginseng and processed P. quinquefolius. Currently known biomarkers such as ginsenoside Rf and F11 have been used for the analysis using the UPLC-photodiode array detector. However, this method was not able to fully discriminate between the two processed ginseng genera. Thus, an optimized UPLC-QTOF-based metabolic profiling method was adapted for the analysis and evaluation of two processed ginseng genera. As a result, all known biomarkers were identified by the proposed metabolomics, and additional potential biomarkers were extracted from the huge amounts of global analysis data. Therefore, it is expected that such metabolomics techniques would be widely applied to the ginseng research field.

The dissipation behaviors of acetamiprid and chlorantraniliprole in kimchi cabbages were studied under open-field conditions. A simple and rapid analytical method was developed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The multiple reaction monitoring (MRM) conditions of two pesticides were optimized to quantify and identify the pesticide residues. Sample preparation was performed by the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. Average recovery rates at the different spiked levels (0.05 and 0.25 mg/kg) were in the range of 103.6−113.9% (acetamiprid) and 80.8−91.2% (chlorantraniliprole), and the relative standard deviations were ≤4.3% for all. The dissipation kinetics were assessed using first-order equations after spraying acetamiprid and chlorantraniliprole individually on kimchi cabbages. The biological half-lives in field 1 and 2 were 5.2 and 6.3 days (acetamiprid) and 10.0 and 15.2 days (chlorantraniliprole), respectively. Based on the dissipation equations, the pre-harvest residue limits (PHRLs) corresponding to each day before harvest were suggested as the guidelines to meet the MRL on harvest day. It was also predicted that the terminal residues observed after multiple sprayings (three and seven days) would be below the MRL when harvested, in compliance with the established pre-harvest intervals.

Multiresidual pesticide determination in a biological sample is essential for an immediate decision and response related to various pesticide intoxications. A rapid and simultaneous analytical method for 260 pesticides in human urine was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). High speed positive/negative switching electrospray ionization (ESI) mode was used, and scheduled multiple reaction monitoring (MRM) was optimized. Three versions of scaled-down QuEChERS procedures were evaluated, and the procedure using non-buffer reagents (magnesium sulfate and sodium chloride) and excluding cleanup steps was selected for optimum pesticide extraction. The limit of quantitation (LOQ) in this methodology was 10 ng/mL for each target pesticide, and correlation coefficient (r2) values of calibration curves were ≥0.988 (linearity range; 10–250 ng/mL). In accuracy and precision tests, the relative error ranges were −18.4% to 19.5%, with relative standard deviation (RSD) 2.1%–19.9% at an LOQ level (10 ng/mL), and −14.7% to 14.9% (RSD; 0.6%–14.9%) at higher concentrations (50, 150, and 250 ng/mL). Recovery range was 54.2%–113.9% (RSD; 0.3%–20.0%), and the soft matrix effect (range; −20% to 20%) was observed in 75.4% of target pesticides. The established bioanalytical methods are sufficient for application to biomonitoring in agricultural exposures and applicable in the forensic and clinic.

We carried out a validation study on AURIC FUV/EUV dayglow calculation with OII 834AA, OI 989AA, OI 1027AA, NII 1085AA, NI 1134AA, NI 1200AA, OI 1304AA, OI 1356AA dayglows observed by STP78-1 satellite. Comparison between calculated and observed values indicates that they are in agreement within about 20% for dayglows of OII 834AA, OI 1027AA, NI 1200AA, OI 1304AA. However, the calculated intensities of OI 989AA, NII 1085AA and NI 1134AA are only 42, 74 and 45% of the observed values, respectively, showing serious differences from the observation. It was surmised that the differences in OI 989AA and NI 1134AA are due to incomplete calculation of radiative transfer and uncertain photochemical processes in AURIC model, respectively. The difference in NII 1085AA is conjectured to be due to variation of the input solar EUV flux rather than due to AURIC model itself. For up-looking dayglows from the satellite, the calculated values from AURIC are all less than those of STP78-1, which may imply that AURIC model does not include dayglow contribution from regions below the satellite altitude when it computes dayglows in up-looking direction. The differences are particularly serious for OI 989AA, NI 1134AA, NI 1200AA dayglows. The calculated latitudinal variation of OII 834AA dayglow is also significantly different from the observed one, especially at mid-latitude regions. This may be due to inability of MSISE-90 (in input of AURIC) to simulate oxygen atom densities at mid-latitudes during auroral storms at those days of STP78-1 observations. Our findings of the validation study should be resolved when AURIC model is revised in future.