• Journal of Life Science
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• v.31 no.2
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• pp.209-218
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• 2021

This study aimed to evaluate the anti-obesity effects of Cudrania tricuspidata leaf extract in the order of leaf development on the shoot (L0, L1, L2, L3, L4, and L5). The leaves at the apex of a Cudrania tricuspidata shoot were classified as L0; the next leaves of the apex were classified as L1, L2, L3, and L4 from highest to lowest; and the lowest leaf was classified as L5. A series of 70% ethyl alcohol leaf extracts were screened for the inhibitory effects of adipogenesis in 3T3-L1 preadipocytes. We found that the apical leaf extract of Cudrania tricuspidata (CTL0) was the most effective. Next, a study was conducted on the inhibitory action mechanism of CTL0. Treatment with CTL0 significantly suppressed the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by the decrease in lipid droplet content observed with Oil Red O staining. Treatment with 12.5 ㎍/ml, 25 ㎍/ml, and 50 ㎍/ml of CTL0 significantly reduced the lipid droplet content. Glucose and cellular triglyceride concentrations were reduced in the 3T3-L1 cells on the CTL0-treated medium compared to the differentiation medium (DM control, DMEM + insulin + dexamethasone + rosiglitazone). Compared with DM, CTL0 significantly inhibited the expression of key pro-adipogenic transcription factors, including peroxisome proliferator-activated receptor γ (PPARγ), LPL, A-FABP, and Glut4. These findings show that CTL0 extract has potent anti-obesity effects.

• (The)Study of the Eastern Classic
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• no.55
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• pp.223-264
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• 2014

Yeoncheon Hong Seok-joo(淵泉 洪奭周: 1774-1842) faithfully followed a policy of restoration of literary style of king Jeongjo. He was an young vassal after 1794 and influenced by Jeongjo because Yeoncheon was around the king. Furthermore, he had comparatively favorable working period as a vassal(仕宦期, 1795-1836) after death of Jeongjo(1800) while establishing his own academic viewpoint. Therefore, a study about art theory of Yeoncheon Hong Seok-joo is one about logical system to accept various desires for change of then while not getting rid of scope of Neo-Confucianism after Jeongjo. It is catched that exchange of Hong Seok-joo and Jeong Yak-yong was made relating to study of Sangseo. Hong Seok-joo and Jeong Yak-yong absorbed in study of Sangseo, which is come from putting importance on 6 scriptures (經) among studies of scriptures by both of them. Through this, they aimed to re-discover ideology of original Confucian studies as one for cultivating oneself and governing people (修己治人之學). Dasan and Yeoncheon have something in common that they were young vassals who were cultivated as a guarding power for Jeongjo centered on Gyujanggak. They were largely fit to view of literature(文體觀) of Jeongjo. Hong Seok-joo distinguished function of prose(文) and poetry(詩) into teaching moral(明敎) and moving people(感人) in the category of Mun-yi-jae-do(文以載道) based on thoughts of 'literature is linguistic device for Taoism '(道本文末)' which is a core concept of literature theory based on Neo-Confucianism. He gave a careful attention on instructional and social function in prose while on emotional understanding that puts importance on temper and the secrets of nature in poetry. Hong Seok-joo regarded moral impression and edification through this as a core of artistic creation based on Segyoseol(世敎說). Furthermore, expressions such as 'Heunggwangunwon(興觀群怨)' or 'Yeohangguyo(閭巷謳謠) which are mentioned as important elements in his artistic works put importance on actual existence of objective things in artistic activity and this is connected to an attitude to require description fit to fact. So, it is assumed that such expression style aimed for features of genre painting in painting arts. Understanding of the study of ancient documents by Yeoncheon developed from critical perspective. He criticized the study of ancient documents, saying it as first, Pasoijisul(破碎之術), second, Dotaekjisul(塗澤之術), third, Hoimojisul(毁侮之術). Jeong Yak-yong criticized ' theory on the Odes' from viewpoint of theory of Mun-yi-jae-do(文以載道) based on Neo-Confucianism. He stressed political and social function of Sipeon and general poetry in "the Odes" and reinterprets discourses about poetry of Zhu Xi based on his own opinion. He says that poems of national fashion do political and social criticism. The theory of national fashion by Jeong Yak-yong clearly discloses his thoughts that stress practical role of noblemen in the social and political context.

• (The)Study of the Eastern Classic
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• no.34
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• pp.225-255
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• 2009

Few data on the epigraph from the Bal-Hae Dynasty have been reported so far. The present paper, based on an examination of the style of the epitaphic tombstones of Princess Jeong-Hye and Princess Jeong-Hyo, investigates the historical formation and characteristics of Balhae's epitaphic style and its influences on the posterior periods. The epitaphs from the Bal-Hae Dynasty have the following epigraphic characteristics and historical significances. First, Bal-Hae's epitaphs are similar to those from the Goguryeo Dynasty in the sense that they are angular in their form. Tombstones with angular head first appeared during the East Han period. During the Wi-Jin period, however, as tombstones were not allowed to be erected in front of the tomb, small-sized epitaphic tombstones were set up inside tombs. Typical tombstones from the Dang Dynasty had stone pole and square cover. Unlike those from the Dang and the Tong-Il Silla Dynasties, however, the epitaphs from Bal-Hae had angular head in their tombstone body. The Bal-Hae's angular headed tombstones are very likely to testify that Goguryeo's epitaphs, which features an influence from the Wi-Jin Nambuk-Jo period, in turn exerted an effect on those from the Bal-Hae Dynasty. Second, Bal-Hae's epitaphic tombstones are characterized by their hexagonal head,which were modified from the then typical pentagonal head by cutting out the sharp point. The hexagonal head, which has not been found in its neighboring countries during the same historical period, is peculiar to the epitaphic tombstones from the Bal-Hae Dynasty. Third, the edge lines and ornamental figures first appeared in Bal-Hae's epitaphic tombstones, as seen in those of Princess Jeong-Hye. In the fa?ade of the epitaphic tombstone, a carved line demarcates its rectangular body and trapezoidal head. Four faces of the body stonehave two parallel lines in their edges within which vignette was inscribed, and the trapezoidal head part was ornamented with flower figures. Fourth, Bal-Hae's epitaphic tombstone had an extensive influence on the posterior countries in its neighborhood. The epitaphic tombstones in the Bal-Hae style are very often found in those of the Goryeo Dynasty and the Yo Dynasty which were greatly influenced from Bal-Hae. The vestiges of Bal-Hae's epitaphic style are also found in those from the Song, the Geum, and the Won Dynasties.

• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.267-274
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• 2020

This study was conducted to estimate genetic parameters for growth and egg production traits in Black Korean native chicken (L strain) and Korean White Leghorn (F, K strains) using a multi-traits animal model BLUP. Traits used for this study were body weight at 150 days (BW150) and 270 days (BW270), age at first egg (DAY1st), egg weight at first egg (EW1st) and 270 days (EW270), and number of eggs laid by 270 days (EP270), and included 68,688 pedigree and 123,905 performance records collected from 2001 to 2013. In L, F, K strains, heritability estimates of BW150 were high (0.48, 0.52 and 0.50, respectively); of BW270 were high (0.56, 0.57 and 0.56); of DAY1st were medium to high (0.45, 0.39 and 0.31); of EW1st were low (0.15, 0.16 and 0.15); of EW270 were high (0.58, 0.55 and 0.59) and of EP270 were moderate (0.22, 0.21 and 0.20). The genetic and phenotypic correlation of DAY1st with EP270 were highly negative (-0.73 to -0.63 and -0.48 to -0.42). The genetic and phenotypic correlation of EP270 with BW150 and BW270, respectively were low negative (-0.16 to 0.01 and -0.14 to -0.03) and low to moderate positive (-0.08 to 0.07 and -0.13 to 0.04). The genetic and phenotypic correlation of EW270 with BW150 and BW270, respectively were moderate to high positive (0.39 to 0.49 and 0.36 to 0.46) and (0.29 to 0.33 and 0.34 to 0.37). The study showed that there is a potential for genetic improvement of Korean Indigenous chicken through selection program.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.1
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• pp.1-12
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• 2021

To investigate the effect of freshwater discharge on the seawater circulation in the semi-closed harbor, a 3-D hydrodynamic model was applied to the International Ferry Terminal (IFT). The model run is conducted for 45 days (from May 15 to June 30, 2020), and the reproducibility of the model for time-spatial variability of current velocity and salinity was verified by comparison with model results and observation data. There are two sources of freshwater towards inside of the IFT: Han River and water reservoir located in the eastern part of IFT. In residual current velocity results, the two-layer circulation (the seaward flow near surface and the landward flow near bottom)derived from the horizontal salinity gradient in only considering the discharge from a Han River is more developed than that considering both the Han River and water reservoir. This suggests that the impact of freshwater from the reservoir is greater in the IFT areas than that from a Han River. Additionally, the two-layer circulation is stronger in the IFT located in southern part than Incheon South Port located in northern part. This process is formed by the interaction between tidal current propagating into the port and freshwater discharge from a water reservoir, and flow with a low salinity (near 0 psu) is delivered into the IFT. This low salinity distribution reinforces the horizontal stratification in front of the IFT, and maintains a two-layer circulation. Therefore, local sources of freshwater input are considered to estimate for mass transport process associated with the seawater circulation within the harbor and It is necessary to perform a numerical model according to the real-time freshwater flow rate discharged.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.7
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• pp.873-880
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• 2020

After pre-treatment of oyster shells according to particle size (0 ~ 1, 1 ~ 2, 2 ~ 5 mm) and pyrolysis temperature (400(P400), 500(P500), 600(P600), 800(P800)℃), changes in the properties of sediments mixed with pre-treated oyster shells were investigated. The primary component of the oyster shell was changed from CaCO3 to CaO at temperatures above 700℃. The Ca2+ concentration in P800 was 790 mg/L, which was 2 ~ 3 times higher than those in the control and other experimental samples. Ca2+ elution significantly increased at the pyrolysis temperature over than 600℃. In oyster shells pyrolyzed over 600℃, the pH of the pore water increased by 0.1 ~ 0.5, due the hydrolysis of CaO formed by the pyrolysis of CaCO3. The PO4-P of the overlying and pore water in P600 and P800 were 0.1 ~ 0.2 mg/L lower than those of the control. The increased pH and elution of Ca2+ from oyster shells should suppress the upwelling of PO4-P from the sediment. Based on the above results, it was confirmed that the pyrolysis temperature of oyster shells influenced NH3-N and PO4-P concentrations in the sediment; however, the particle size of oyster shells had little effect. The results of this study can be used as a foundation for research on the use of pyrolyzed oyster shells to improve low-contamination coastal benthic environments.

• Tuberculosis and Respiratory Diseases
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• v.85 no.1
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• pp.37-46
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• 2022

Background: Although respiratory tract infection is one of the most important factors triggering acute exacerbation of chronic obstructive pulmonary disease (AE-COPD), limited data are available to suggest an epidemiologic pattern of microbiology in South Korea. Methods: A multicenter observational study was conducted between January 2015 and December 2018 across 28 hospitals in South Korea. Adult patients with moderate-to-severe acute exacerbations of COPD were eligible to participate in the present study. The participants underwent all conventional tests to identify etiology of microbial pathogenesis. The primary outcome was the percentage of different microbiological pathogens causing AE-COPD. A comparative microbiological analysis of the patients with overlapping asthma-COPD (ACO) and pure COPD was performed. Results: We included 1,186 patients with AE-COPD. Patients with pure COPD constituted 87.9% and those with ACO accounted for 12.1%. Nearly half of the patients used an inhaled corticosteroid-containing regimen and one-fifth used systemic corticosteroids. Respiratory pathogens were found in 55.3% of all such patients. Bacteria and viruses were detected in 33% and 33.2%, respectively. Bacterial and viral coinfections were found in 10.9%. The most frequently detected bacteria were Pseudomonas aeruginosa (9.8%), and the most frequently detected virus was influenza A (10.4%). Multiple bacterial infections were more likely to appear in ACO than in pure COPD (8.3% vs. 3.6%, p=0.016). Conclusion: Distinct microbiological patterns were identified in patients with moderate-to-severe AE-COPD in South Korea. These findings may improve evidence-based management of patients with AE-COPD and represent the basis for further studies investigating infectious pathogens in patients with COPD.

• Journal of Bio-Environment Control
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• v.31 no.2
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• pp.79-89
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• 2022

With the wide use of greenhouses, the working hours have been increasing inside the greenhouse for workers. In the closed ventilated greenhouse, the internal environment has less affected to external weather during making a suitable temperature for crop growth. Greenhouse workers are exposed to organic dust including soil dust, pollen, pesticide residues, microorganisms during tillage process, soil grading, fertilizing, and harvesting operations. Therefore, the health status and working environment exposed to workers should be considered inside the greenhouse. It is necessary to secure basic data on particulate matter (PM) concentrations in order to set up dust reduction and health safety plans. To understand the PM concentration of working environment in greenhouse, the PM concnentrations were monitored in the cut-rose and Hallabong greenhouses in terms of PM size, working type, and working period. Compare to no-work (move) period, a significant increase in PM concentration was found during tillage operation in Hallabong greenhouse by 4.94 times on TSP (total suspended particle), 2.71 times on PM-10 (particle size of 10 ㎛ or larger), and 1.53 times on PM-2.5, respectively. During pruning operation in cut-rose greenhouse, TSP concentration was 7.4 times higher and PM-10 concentration was 3.2 times higher than during no-work period. As a result of analysis of PM contribution ratio by particle sizes, it was shown that PM-10 constitute the largest percentage. There was a significant difference in the PM concentration between work and no-work periods, and the concentration of PM during work was significant higher (p < 0.001). It was found that workers were generally exposed to a high level of dust concentration from 2.5 ㎛ to 35.15 ㎛ during tillage operation.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.162-168
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• 2020

Purpose: The purpose of this study was to suggest an appropriate treatment method by comparing nonsurgical treatment and surgical treatment for enchondroma in the hands and feet. Materials and Methods: Seventy four cases with enchondroma of the hands and feet from January 1996 to March 2017 were selected to evaluate the functional outcomes. Thirty cases were treated with nonsurgical treatment, and 44 cases were treated with surgical treatment, such as curettage only or curettage with a bone graft. The mean follow-up period was 18.1 months. The functional results were analyzed using the Wilhelm and Feldmeier formula. Results: The mean age was 38 years, and the age range was between eight and 69 years. According to the Wilhelm and Feldmeier formula, the mean score of hand enchondroma was 3.09±0.85 and 3.20±0.91 in the non-operative and operative group, respectively. The mean scores of the foot except for the grip strength were 2.57±0.79 and 2.75±0.50, respectively. No significant difference was observed according to the functional results. Among the 18 cases of enchondroma with pathological fractures, nine cases were treated non-surgically and nine cases were treated by surgically. In all 18 cases, complete bone healing was observed at the final follow-up. Conclusion: Relatively satisfactory results were obtained in both surgical and nonsurgical treatment and there was no significant difference in functional outcomes. In cases of enchondroma in the hands and feet, nonsurgical treatment can also be a good treatment option.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.3
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• pp.180-188
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• 2022

This study was conducted to determine the optimal sowing date for seed yield of summer oat (Avena sativa L.) cultivars "Darkhorse (DH)" and "Highspeed (HS)" in Wanju, Jeonbuk province between 2017 and 2018. We investigated seed yield from 4 sowing dates: July 15, July 30, August 15, and August 30. We evaluated the agronomic characteristics of summer oats (DH and HS). We found the heading date of all cultivars to be within 50 days. Delayed sowing resulted in significantly increased plant height for both years and cultivars. There was no significant difference in spike length of DH and HS which ranged from 12.8 to 17.8 cm. The sowing date of July 30 produced a higher number of grains per spike, but this yield differed significantly by year and cultivars. In 2017, the first sowing resulted in the lowest DH yield at 132 kg per 10a, while the second sowing had the highest yield at 227 kg. HS yield was the lowest in the first sowing at 126 kg and the highest in the third sowing at 219 kg. In 2018, DH had the lowest yield from the first sowing at 184 kg per 10a, and the highest from the second sowing at 240 kg, but there was no significant difference between these yields. The first sowing for HS gave the lowest yield at 160 kg, and the second sowing produced the highest at 258 kg. The germination rate of harvested seeds from each sowing date in 2017 and 2018 was found to be higher than 85% and there was no significant difference between the two cultivars in the 2018 germination rate test. Thus, we found the optimal sowing date for summer cultivation of oats for the highest seed yield to be between July 30 (second sowing) and August 15 (third sowing).