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Background The vascular flora of the Dokdo Islands has been reported, based on primary collections made in 2012 and 2013 and legacy botanical literature. The Dokdo Islands are the remotest islands of Korea, located in the East Sea approximately 87 km from Ulleungdo Islands. They comprise two main volcanic islands, Dongdo (east islands) and Seodo (west islands) and minor islets surrounding the two main islands. This research was conducted to document vascular plant species inhabiting Korea's most inaccessible islands. We present a georeferenced dataset of vascular plant species collected during field studies on the Dokdo Islands over the past seven decades. New information In the present inventory of the flora of Dokdo, there are listed 108 species belonging to 78 genera and 39 families, including 93 native species and 15 newly human-induced naturalised species for these Islands' flora. The Poaceae and Asteraceae families are the most diverse, with 22 and 15 taxa, respectively. Some of the previously-listed taxa were not found on Dokdo probably because they are rare and the limited time did not allow collectors to find rare species. The spread of introduced species, especially the invasive grass Bromus catharticus Vahl., affects several native species of Dokdo flora. [ABSTRACT FROM AUTHOR]

The heat wave in East Asia is examined by using empirical orthogonal function analysis to isolate dominant heat-wave patterns in the ground-based temperature observations over the Korean Peninsula and China and related large-scale atmospheric circulations obtained from the National Centers for Environmental Prediction–National Center for Atmospheric Research Reanalysis 1 during 1973–2012. This study focuses particularly on the interannual variability of heat waves and its decadal change. The analysis identifies two major atmospheric teleconnection patterns playing an important role in developing typical heat-wave patterns in East Asia—the Scandinavian (SCAND) and the circumglobal teleconnection (CGT) patterns, which exhibit a significant decadal change in the interannual variability in the mid-1990s. Before the mid-1990s, heat-wave occurrence was closely related to the CGT pattern, whereas the SCAND pattern is more crucial to explain heat-wave variability in the recent period. The stationary wave model experiments suggest an intensification of the SCAND pattern in the recent period driven by an increase in land–atmosphere interaction over Eurasia and decadal change in the dominant heat-wave patterns in East Asia. [ABSTRACT FROM AUTHOR]

The inter-decadal variation of the positive relationship between the tropical Atlantic sea surface temperature (SST) and Korean precipitation during boreal summer season during 1900-2010 is examined. The 15-year moving correlation between the Tropical Atlantic SST (TAtlSST) index (SST anomalies from 30°S to 30°N and 60°W to 20°E) and Korean precipitation (precipitation anomalies from 35°-40°N to 120°-130°E) during June-July-August exhibits strong inter-decadal variation, which becomes positive at the 95% confidence level after the 1980s. Intensification of the linkage between the TAtlSST index and Korean precipitation after the 1980s is attributed to global warming via the increased background SST. The increase in the background SST over the Atlantic provides background conditions that enhance anomalous convective activity by anomalous Atlantic SST warming. Therefore, the overall atmospheric responses associated with the tropical Atlantic SST warming could intensify. The correlation between the TAtlSST index and Korean precipitation also exhibits strong inter-decadal variation within 1980-2010, which is over 0.8 during early 2000s, while it is relative low (i.e., around 0.6) during the early 1980s. The enhanced co-variability between the tropical and the mid-latitude Atlantic SST during the early 2000s indicates the intensification of TAtlSST-related Rossby wave source over the mid-latitude Atlantic, which excites stationary waves propagated from the Atlantic to the Korean peninsula across northern Europe and northeast Asia. This Rossby-wave train induces a cyclonic flow over the northern edge of the Korea, which intensifies southwesterly and results in precipitation over Korea. This observed decadal difference is well simulated by the stationary wave model experiments with a prescribed TAtlSST-related Rossby wave source over the mid-latitude Atlantic. [ABSTRACT FROM AUTHOR]

Objectives: Studies on Clostridium difficile are rare in Korea. We investigated the epidemiological characteristics of C. difficile isolates from patients with C. difficile-associated disease (CDAD) in Korea. Methods: Multiplex polymerase chain reaction was performed to detect the presence of tcdA and tcdB toxin genes. Antimicrobial susceptibility test was carried out by the disk-dilution method. C. difficile strains were subtyped by automated repetitive-element palindromic PCR (rep-PCR). Results: Among patients with CDAD, 73 (25.8%), 32 (11.3%), 32 (11.3%), and 26 (9.2%) suffered from pneumonia, cancer or neoplasm, diabetes, and colitis, respectively. Of all stool samples, 43 samples (15.2%) were positive for C. difficile strains. We observed two expression patterns of toxin genes: tcdA+/tcdB+ (86% isolates) and tcdA-/tcdB+ (14% isolates), with all isolates expressing tcdB. Furthermore, some isolates were resistant to clindamycin (65%), ampicillin (56%), and cefazolin (40%), but all were susceptible to vancomycin and metronidazole. The tested samples were classified into diverse clusters using automated rep-PCR. Conclusion: Our findings revealed the characteristics and antibiotic resistance of C. difficile isolates from patients in Korea. The epidemiological data may provide valuable insight into development of treatment strategies for C. difficile infections in Korea. [ABSTRACT FROM AUTHOR]

Nuruk contributes to the unique characteristics of Korean alcoholic beverages. In this study, the effects of nuruk extracts (NE) on anti-oxidant characters, melanogenesis, and anti-photoaging activity were investigated. NEs were obtained from the 70% ethanol extracts of six types of nuruk, which have been used in brewing of fermented alcohol beverages in Korea. First, various antioxidant characteristics were identified in terms of 2,2'-azino-bis(3-ethylbenzthiozoline-6-sulphonic acid) (ABTS) radical scavenging activity, superoxide dismutase (SOD) expression, and inhibition of xanthine oxidase activity. NE#4 exhibited potent ABTS radical scavenging activity (IC50 = 19.51 μg/mL). Compared with NE#4, relatively lower levels of activity were observed for NF#3 and NE#6, with IC50 values of 90.99 and 76.88 μg/mL, respectively. According to results of western blot analysis for determination of SOD expression in H2O,-treated HepG2 cells, NE#5 and NE#6 induced a dramatic increase in the expression ratio of SOD, compared to the group treated with H2O2 only. Activity of xanthine oxidase, which converts xanthine into uric acid, generating superoxide ions, was inhibited by NE#4 and NE#6 in a dose-dependent manner. NE#4 induced significant inhibition of mushroom tyrosinase activity. A reduction in cellular melanin contents of 80% was observed in B16F1 melanocytes treated with NE#5 and NE#6; these effects were similar to those of arbutin at 100 μM. In addition, gelatin zymography and reverse transcription-PCR analysis were performed for assessment of anti-photoaging activity of Nuruk. Treatment with NE#6 resulted in dramatically inhibited activities of matrix metalloproteinase (MIMIP)-2/-9, suppressed expression of MMP-1, and increased expression of type-1 procollagen. Results of gelatin zymography for NE#4 and NE#5 were similar, to a slightly lesser degree. These results suggest the potential of NE#4 and NE#6 as natural ingredients for use in functional foods and cosmetics. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to evaluate the changes of position during sleep as determined by polysomnography before and after upper airway surgery for obstructive sleep apnea syndrome in patients with no response to surgery ("nonresponse group") and in those who did have a response to surgery ("response group"). Methods: We analyzed a total of 106 polysomnograms from 53 subjects and compared the preoperative-postoperative differences in the frequency of positional changes during sleep and the distribution of sleep positions between the nonresponse group (n = 25) and the response group (n = 28). Surgical response was defined as a greater than 50% decrease in the postoperative apnea-hypopnea index. Results: The positional change index in the response group was significantly reduced (from 4.2 ± 3.8 to 2.6 ± 1.6; p = 0.038), whereas the positional change index in the nonresponse group did not significantly change (from 3.4 ± 2.0 to 3.4 ± 2.1 ; p = 0.861). The proportion of sleep time spent in the supine position did not significantly change in the nonresponse group (from 62.4% ± 18.1% to 60.5% ± 21.3%; p = 0.904) or the response group (from 55,5% ± 23,9% to 60.1% ± 23.1%; p = 0.412). [ABSTRACT FROM AUTHOR]

Objectives: Pediatric obstructive sleep apnea syndrome (OSAS), like adult OSAS, is characterized by intermittent upper airway collapse during sleep and is associated with anatomic and neuromuscular factors. However, the clinical manifestations, diagnostic criteria, and polysomnographic findings of OSAS in children are likely to be different from those in adults. The purpose of this study was to identify the characteristics that distinguish the clinical manifestations and polysomnographic findings of OSAS in children from those in adults. Methods: The study population consisted of 34 children (mean age, 7.6 years; range, 4 to 16 years) with OSAS and 33 adults (mean age. 40.1 years; range, 18 to 58 years) with OSAS. We compared various clinical manifestations, such as body mass index, tonsil size, severity of symptoms and signs, and polysomnographic data, between these groups. Results: Obesity was more common among the adults, whereas tonsillar hypertrophy was more common among the children. There were significant differences between the groups in the severity of symptoms and signs, including witnessed apnea, daytime sleepiness, morning headache, memory reduction, and daytime fatigue. In the children with OSAS, slow- wave sleep was relatively well preserved, and respiratory events such as apnea and hypopnea occurred mainly during rapid eye movement sleep. Conclusions: The clinical manifestations and polysomnographic findings in children with OSAS differ from those in adults with OSAS. [ABSTRACT FROM AUTHOR]

Objective: To determine the contribution of maternal lipids in predicting large-for-gestational age (LGA) newborns born to women with gestational diabetes mellitus (GDM). Design: Retrospective study. Setting: Yonsei University Health System, Korea. Population: A total of 104 women diagnosed with GDM between January 2000 and June 2008. Methods: Women who were positive on the 50 g oral glucose challenge test (24-28 weeks' gestation) and who were referred patients suspected of GDM underwent a 3 hours, 100 g oral glucose tolerance test for GDM diagnosis. Maternal fasting serum triglycerides and total, high-density lipoprotein (HDL), and low-density lipoprotein cholesterol levels were determined at 24-32 weeks' gestation. Logistic regression analysis was performed to determine maternal parameters independently associated with delivering LGA newborns at term. Main Outcome Measures: Risk contributions for LGA newborns. Results: Maternal fasting serum triglyceride levels were significantly higher in mothers of LGA newborns compared with other mothers; however, no significant correlations were found between newborn birthweight and maternal fasting glucose, total cholesterol, or HDL cholesterol levels. After adjusting for confounding variables including prepregnancy body mass index, weight gain during pregnancy, age, and parity, maternal hypertriglyceridemia at 24-32 weeks' gestation remained an independent parameter for identifying term LGA newborns. Conclusions: In GDM pregnancies, determining maternal serum triglyceride levels during midpregnancy may help identify women likely to give birth to LGA newborns. [ABSTRACT FROM AUTHOR]

The drastic expansion of cities and the rapid economic growth in Korea have caused dramatic increases to demand from groundwater supplies for drinking, domestic, agricultural and industrial water usage. The Ministry of Construction and Transportation and the Korea Water Resources Corporation have constructed and operated the National Groundwater Monitoring Network (NGMN) throughout the country since 1995. The NGMN, an official project establishing a total of 320 groundwater monitoring stations, was completed in 2005. Each national groundwater monitoring station serves as a baseline and primary station to monitor long-term general trends in water-level fluctuations and in groundwater quality. The present NGMN and its monitoring capabilities were evaluated to enhance the efficiency of groundwater monitoring and to meet the new societal conditions. Based on reviews and evaluations, some suggestions and recommendations are made with regard to improvements of the national network, including the installation of rainfall gauges in groundwater monitoring stations, gathering groundwater data every hour instead of every 6 h as at present, involving major cations and anions in the regular and periodic chemical analyses, regular periodic analyses of collected groundwater data, and construction of 199 additional groundwater monitoring stations to supplement the existing groundwater monitoring network. [ABSTRACT FROM AUTHOR]

This paper introduces T-DMB transmission system in Korea based on Eureka-147 DAB and presents a new architecture of transmission system for digital multimedia services. For transmission of the digital multimedia contents in mobile environment by using the existing DAB, we developed a T-DMB processor which performs T-DMB encoding and insertion of the media stream into the existing DAB transmission system. After the implemented T-DMB processor can be connected to the front of the commercial Eureka-147 DAB system, and the performance of the T-DMB system is confirmed through the T-DMB experimental broadcasting in Korea. [ABSTRACT FROM AUTHOR]

Context.--Because of the limited number of available primary bladder paraganglioma (PBPG) cases, the rates of succinate dehydrogenase (SDH) mutations and the clinicopathologic characteristics of SDH-deficient tumors have not been fully studied. Objective.--To define the clinicopathologic and molecular characteristics of PBPGs. Design.--A total of 52 PBPGs were collected retrospectively. SDHA and SDHB immunohistochemical stains were performed. In cases of SDHB expression loss, mutation analyses of SDHB, SDHC, and SDHD were performed. Results.--The clinicopathologic features were analyzed for 52 cases (M:F = 27:25), with a mean age of 56 years (range, 22-79 years). Tumor sizes were 0.5 to 8 cm (mean, 2.4 cm). Tumor necrosis was present in 5 of 52 cases (10%), involvement of muscularis propria in 41 (79%), and lymphovascular tumor invasion in 6 (12%). During a mean follow-up period of 41 months (range, 1-161 months), 3 of 52 patients (6%) developed metastases, but no one died from the disease. Immunohistochemistry for SDHA and SDHB showed that all cases were SDHA intact. Among them, 43 cases had intact SDHB, whereas 9 cases were SDHB deficient. Compared with the SDHB-intact cases, the SDHB-deficient cases were characterized by large tumor sizes (4.5 versus 1.9 cm; P < .001), a higher number of mitoses per 10 high-powered fields (2.6 versus 0.1; P = .002), and frequent lymphovascular tumor invasion (33% versus 7%; P = .02) and metastases (22% versus 2%; P=.02). Mutational analyses for SDHB, SDHC, and SDHD were performed in 9 SDHB-deficient cases. Among them, 6 cases were successfully sequenced and revealed SDHB mutations only. Conclusions.--Large tumor size, a higher number of mitoses, and the presence of lymphovascular tumor invasion and SDHB mutations suggest malignant paraganglioma. [ABSTRACT FROM AUTHOR]

Doenjang is one of the most popular traditional fermented foods in Korea, and mainly used as an ingredient in Doenjang soup easily found on Korean table. In this study, we examined the change of isoflavones content during fermentation process of Doenjang preparation by traditional method. Concisely, Doenjang was made by traditional method with Meju (Koji) and salt water. Doenjang was collected at various fermentation periods and was subjected to isoflavone analysis using HPLC. Daidzin, glycitin and genistin, major glycosides of isoflavones present in soybean, were extensively metabolized into their aglycones. The total isoflavone content of Meju was 618 ¡¾ 75 ¥ìg/g dry matter while raw material contain 3,137 ¡¾ 174 ¥ìg/g dry matter, suggesting significant loss by Aspergillus species during Meju preparation. The genistein in Doenjang and Meju was the most abundant with 411¥ìg/g dry matter in Doenjang at 60th day of fermentation. In conclusion, the content of free isoflavones was largely increased and total isoflavone content was greatly reduced during Doenjang manufacturing, in particular, in the process of Meju preparation with little change in isoflavone composition and content during fermentation (aging) process. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between prostate specific antigen (PSA) level and prostate volume (PV) according to age in a community-based population of Korean men enrolled in a large-scale screening program. Methods: A total of 35,223 men who enrolled in the Korean Prostate Health Council Screening Program from January 2001 to December 2011 were included in this study. Patients with a serum PSA level of >10 ng/mL or younger than 40 years were excluded. We analyzed PSA level and PV as measured through transrectal ultrasonography according to stratified age cohorts. We used Pearson correlation and linear regression analysis according to age to describe the correlation between PSA level and PV. Results: Mean PSA level and mean PV increased significantly with age (all P values <.001). Based on data from 5 age cohorts, mean PSA level increased about 0.3 ng/mL every 10 years and mean PV increased about 3 mL every 10 years. The slope of the linear regression between PSA level and PV was 4.582, and the slope of the linear regression increased with age. We derived equations relating PSA level and PV for the various age cohorts. Conclusion: Based on a large-scale health screening program, we derived equations relating PSA level to PV according to age group. These data provide a baseline for the normal population by avoiding the interventional bias of urinary symptoms, in contrast to previous data derived from patients who visited hospitals because of prostate-related health concerns. [Copyright &y& Elsevier]

Background: Recently, several reports issued clevudine induced myopathy in the long term use. Objectives: The aim of this study was to investigate antiviral effects and adverse events of clevudine monotherapy in patients with chronic hepatitis B (CHB). Patients and Methods: The subjects were 110 treatment-naive CHB patients. They were treated with 30 mg clevudine/day for more than six months. Virological and biochemical tests, including that for serum creatine kinase (CK), were monitored at baseline and at 3-month intervals during treatment period. Results: In HBeAg-positive patients, the cumulative rates of virological response were 74.0 %, 68.5 %, and 67.3 % after one, two, and three years of clevudine treatment, respectively. Cumulative rates of HBeAg loss or seroconversion were 17.8 %, 30 %, and 31.5 % after one, two and, three years of clevudine treatment, respectively. In HBeAg-negative patients, the cumulative rates of virological response were 97.3 %, 100 %, and 94.6 %, respectively. Virological breakthrough occurred in 27 patients. The rtM204I mutation in HBV polymerase was predominantly detected. Muscular adverse events were observed in 15 patients. All patients with myopathy recovered after the cessation of clevudine monotherapy. Fluctuations in CK level during the clevudine treatment period were frequently observed irrespective of development of myopathy. Multiple episodes of CK elevation were significantly related to the development of myopathy. Conclusions: Long-term clevudine monotherapy is effective for suppression of serum HBV DNA level and normalization of serum alanine amino transaminase levels, but associated with occurrence of rtM204I mutation. Clevudine-induced muscular adverse events are not uncommon, although they are totally reversible after cessation of the treatment. Muscular adverse events and serum CK level should be carefully monitored during long-term treatment with clevudine. [ABSTRACT FROM AUTHOR]

Abstract: The amount of waste furniture generated in Korea was over 2.4 million tons in the past 3 years, which can be used for renewable energy or fuel feedstock production. Fast pyrolysis is available for thermo-chemical conversion of the waste wood mostly into bio-oil. In this work, fast pyrolysis of waste furniture sawdust was investigated under various reaction conditions (pyrolysis temperature, particle size, feed rate and flow rate of fluidizing medium) in a fluidized-bed reactor. The optimal pyrolysis temperature for increased yields of bio-oil was 450°C. Excessively smaller or larger feed size negatively affected the production of bio-oil. Higher flow and feeding rates were more effective for the production of bio-oil, but did not greatly affect the bio-oil yields within the tested ranges. The use of product gas as the fluidizing medium had a potential for increased bio-oil yields. [Copyright &y& Elsevier]

Abstract: Pine trees comprise over 35% of the forests in Korea, since 1989, pine wilt disease introduced via the Japanese pine sawyer has been infecting many of these trees. As a renewable resource, pine can be converted to bio-oil, gas, and char through pyrolysis. In this study, the pyrolysis characteristics of pine trees were investigated using thermogravimetric analyzer, with most of the materials decomposing between 330 and 370°C at heating rates of 5–20°C/min. The apparent activation energy increased from 145 to 302kJ mol−1 with increasing pyrolysis conversion. The kinetics of pine tree pyrolysis were experimentally and mathematically evaluated. The kinetic parameters were determined using nonlinear least-squares regression of the experimental data assuming first-order kinetics. It was found from the kinetic rate constants that the predominant reaction pathway was A (pine) to gas (C 1−C 4) rather than A to bio-oil at temperatures of 330–370°C. [ABSTRACT FROM AUTHOR]

ABSTRACTThe anti-inflammatory activity of Chungkukjang, a Korean traditional fermented soybean food (Korean-style Natto), was examined for the first time. From the results, it was found that the ethanol extract of Chungkukjang inhibited 5-lipoxygenase from A23187-treated RBL-1 cells, reducing leukoriene production (50 inhibitory concentration 54.1 μg/mL). However, it did not greatly affect cyclooxygenase-2-catalyzed prostaglandin E2and inducible nitric oxide synthase-catalyzed nitric oxide production from lipopolysaccharide-treated RAW 264.7 cells at the same concentration ranges. Since leukotrienes are intimately involved in some allergic disorders, the anti-allergic activity of Chungkukjang was further examined in animal models of passive cutaneous anaphylaxis (type I hypersensitivity) and arachidonic acid-induced ear edema, two well-known in vivomodels sensitive to 5-lipoxygenase inhibitors. After oral administration for 5 consecutive days, Chungkukjang significantly reduced (27.3) passive cutaneous anaphylaxis in rats at 400 mg/kg/day. It also showed in vivoanti-inflammatory activity against arachidonic acid-induced mouse ear edema. Therefore, it is suggested that Chungkukjang may be beneficial for several allergic conditions such as asthma and atopic dermatitis. [ABSTRACT FROM AUTHOR]