• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1306-1313
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• 2011

A liquid fertilizer treated with slurry composting and biofiltration (SCB) process has been applied increasingly on agricultural field but the effects on the soil properties and crop production has not been throughly evaluated. This study was conducted to investigate the effect of the SCB application on soil chemical properties and the growth of radish and corn. SCB liquid fertilizer as a basal fertilization was treated with five levels based on $6kg\;10a^{-1}$ for radish and $10kg\;10a^{-1}$ for corn. The experimental design was the completely randomized block design with five levels and three replicates. Electrical conductivity (EC), $NO_3$-N, Exch. K and Exch. Na increased depending on the treatment levels of SCB. There were no changes in soil organic matter, Avail. $P_2O_5$, Exch. Ca and Exch. Mg. EC, $NO_3$-N and Exch. Na content decreased as precipitation increased. Especially, they decreased up to the initial condition before the treatment after the heavy rainy season in 2008. Although Exch. K decreased at the rainy season, they remained relatively higher content after the experiment on August, 2008. Fresh weight and the amount of N uptake of radish increased due to the levels of SCB, but corn did not present any significant increase. It is recommended that we need to decide the proper amount of SCB as well as the application method on the field to increase the productivity and decrease environmental stress. Additional experiments also need to clarify the effect of the trace element and heavy metal accumulations due to long term application of SCB.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.263-270
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• 2021

This experiment was carried out to determine the effect of CaCl₂ foliar spraying on the inhibition of blossom-end rot (BER) in hot summer paprika (Capsicum annum L. 'Special') cultivation. The effect of CaCl₂ application was examined by the foliar application based on different fruit size, frequency, and spraying time. Also, it was investigated the occurrence and alleviation effect of BER symptom. Foliar application of CaCl₂ (Ca 0.4%) was conducted by treating a fruit and leaf at 4 to 9 nodes above the crown flowers of each plant with 350 mL per week from June 3 to July 1. When the CaCl₂ was sprayed at 7-day intervals for 4 weeks, the Ca content was the lowest in the fruit harvested with BER symptom in 11 to 20 mm of fruit width (FW). Four different regions in both BER symptom and normal fruits showed significant differences of Ca content, the highest was in pedicel, followed by stem-end, middle, and blossom-end. The Ca content increased sharply in normal paprika with 31-40 mm FW, in which Ca content was 78% higher than that of BER. Ca content in the middle and blossom-end of paprika over 21 mm in FW ranged 19.8% to 28.8% in normal fruits and 15.7% to 18.5% in BER, respectively. The incidence of BER increased rapidly by more than 60% in fruits with 31-40 mm FW. While there was no difference in fruit weight among the FW treatment, marketable yield rate was highest in the 21-30 mm FW, and the sugar content was high in the 11-30mm FW. When CaCl₂ was applied three times for 7 days to a paprika having a 21- 30 mm FW, the cell wall-bound (CWB) Ca content was the highest and the rate of BER was lowest with 6.3%. After 10 days of CaCl₂ foliar spray treatment, the CWB Ca content of paprika increased by 2.9 to 3.5 times compared to the control in all treatments. At 7 days after the CaCl₂ foliar spraying once a day at varying spraying time, the leaf burn observed from 9:30 a.m. to 17:00 p.m. and the proline content increased as the spraying time was delayed. Therefore, the CaCl₂ foliar spraying method for reducing of BER occurrence during paprika summer cultivation seems to be appropriate to spray 2-3 times at intervals of 3 days and before 8 a.m. at the time when the FW is 21-30 mm.

• Journal of Life Science
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• v.31 no.9
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• pp.840-848
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• 2021

This study was conducted to estimate annual trends and the environmental effects in the racing records of Jeju horses. The Korean Racing Authority (KRA) collected 48,645 observations for 2,167 Jeju horses from 2002 to 2019. Racing records were preprocessed to eliminate errors that occur during the data collection. Racing times were adjusted for comparison between race distances. A stepwise Akaike information criterion (AIC) variable selection method was applied to select appropriate environment variables affecting racing records. The annual improvement of the race time was -0.242 seconds. The model with the lowest AIC value was established when variables were selected in the following order: year, budam classification, jockey ranking, trainer ranking, track condition, weather, age, and gender. The most suitable model was constructed when the jockey ranking and age variables were considered as random effects. Our findings have potential for application as basic data when building models for evaluating genetic abilities of Jeju horses.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.31-70
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• 2021

The purpose of this paper is to measure the clustering change and analyze empirical results, and choose the clustering ports for Busan, Incheon, and Gwangyang ports by using Hierarchical clustering(single, complete, average, and centroid), Silhouette, and 2SCE[the Second Stage(Type II) cross-efficiency] matrix clustering models on Asian container ports over the period 2009-2018. The models have chosen number of cranes, depth, birth length, and total area as inputs and container TEU as output. The main empirical results are as follows. First, ranking order according to the efficiency increasing ratio during the 10 years analysis shows Silhouette(0.4052 up), Hierarchical clustering(0.3097 up), and 2SCE(0.1057 up). Second, according to empirical verification of the Silhouette and 2SCE models, 3 Korean ports should be clustered with ports like Busan Port[ Dubai, Hong Kong, and Tanjung Priok], and Incheon Port and Gwangyang Port are required to cluster with most ports. Third, in terms of the ASEAN, it would be good to cluster like Busan (Singapore), Incheon Port (Tanjung Priok, Tanjung Perak, Manila, Tanjung Pelpas, Leam Chanbang, and Bangkok), and Gwangyang Port(Tanjung Priok, Tanjung Perak, Port Kang, Tanjung Pelpas, Leam Chanbang, and Bangkok). Third, Wilcoxon's signed-ranks test of models shows that all P values are significant at an average level of 0.852. It means that the average efficiency figures and ranking orders of the models are matched each other. The policy implication is that port policy makers and port operation managers should select benchmarking ports by introducing the models used in this study into the clustering of ports, compare and analyze the port development and operation plans of their ports, and introduce and implement the parts which required benchmarking quickly.

• Archives of Hand and Microsurgery
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• v.23 no.4
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• pp.230-238
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• 2018

Purpose: Metacarpal fractures are common injuries of the hand. They are treated using closed reduction (CR) or open reduction (OR) techniques. The management strategy depends on fracture site characteristic and fixation methods. In this study, we evaluated pre- and postoperative fracture angulation, when metacarpal fractures bad been treated using two different techniques: CR with parallel transverse pinning and OR with plate fixation. Methods: Forty-six patients undergoing anatomic reduction to treat extra-articular metacarpal fractures were recruited. They were included in one of two therapeutic groups: Group 1, CR with parallel transverse pinning (n=21); Group 2, OR with plate fixation (n=25). Fracture angulation values have been measured on pre- and postoperative radiologic images. Values were compared between pre- and postoperative states, and between corresponding measurements of each group. Results: All extra-articular metacarpal fractures were successfully treated without wound related complications or the limit of joint motion. Both groups demonstrated adequate reduction at immediate postoperative period (postoperative angulation of group 1, $20^{\circ}{\pm}7^{\circ}$; group 2, $19^{\circ}{\pm}5^{\circ}$). During the observation at follow-up period, Group 1 exhibited slight recurrence (follow-up angulation of group 1, $24^{\circ}{\pm}10^{\circ}$). Nonetheless, Group 2 showed adequate reduction state in both immediate postoperative and long-term follow-up periods (follow-up angulation of group 2, $18^{\circ}{\pm}6^{\circ}$). Conclusion: Extra-articular metacarpal fractures were successfully restored without functional complications. CR with parallel transverse pinning method exhibited recurrence after pin removal, which necessitates cautious postoperative exercise and monitoring.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.29 no.2
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• pp.87-93
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• 2018

Background and Objectives : Laryngopharyngeal reflux disease (LPRD) is relatively common disease. N-acetyl cysteine (NAC) has both mucolytic and antioxidant effect, also may be beneficial in inflammatory airway diseases. The purpose of this study was to evaluate the efficacy and safety of inhaled NAC therapy in LPRD. Materials and Method : We retrospectively reviewed the medical records of 525 LPRD patients at 12 medical centers. Finally 401 patients subjected to inhaled NAC therapy for 2 months were enrolled in the study. We analyzed the change of Reflux Symptom Index (RSI) and Reflux Finding Score (RFS) after use of NAC for 4 weeks and 8 weeks in addition to the patient's compliance of the treatment. Results : The RSI score significantly decreased from $19.87{\pm}6.34$ to $12.78{\pm}6.93$ after 4 weeks and to $10.65{\pm}7.47$ after 8 weeks. The RFS score also significantly decreased from $9.29{\pm}3.4$ to $7.17{\pm}3.41$ after 4 weeks and to $6.1{\pm}3.73$ after 8 weeks (p<0.05). During the treatment periods, 42 patients (10.4%) reported to have 80 episodes of discomfort. Throat discomfort (33%) and nausea (28%) were most common complaints, but the duration of discomfort was usually less than 4 weeks. Conclusion : Inhaled NAC treatment is highly effective for the reduction of both subjective and objective findings in LPRD patients. This study will provide the evidence of new treatment option for patients with LPRD. However, further studies will be needs to assess the real effect of inhaled NAC therapy as a standard treatment regimen of LPRD.

• Journal of Korean Society of Forest Science
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• v.108 no.2
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• pp.147-167
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• 2019

This study was conducted to analyze forest vegetation structure in the Marugeum (Ridge) area of Gitdaebaegibong to Jukryeong, Baekdudaegan. Data were collected in 298 quadrates through a Braun-Blanquet vegetation survey from April, 2018 to October, 2018. Forest vegetation was classified into 13 vegetation units. A Quercus mongolica community was divided into Morus bombycis, Filipendula glaberrima, Fraxinus sieboldiana, Prunus maackii unit and Q. mongolica typical unit. The M. bombycis unit was further classified into a Deutzia glabrata group and M. bombycis typical group. The F. glaberrima unit was subdivided into a Veratrum oxysepalum group, Arundinella hirta group, and F. glaberrima typical group. The F. sieboldiana unit was divided into a Pinus densiflora group, Larix kaempferi group, and F. sieboliana typical group. The relationship between vegetation units and environmental factors was studied through coincidence analysis and CCA. The F. glaberrima unit (VU 6~8) was distributed by elevation above 1,200 m and other vegetation units were distributed below 1,200 m. Results of the CCA analysis showed that the F. glaberrima unit distribution is positively correlated with elevation. As a result of species diversity, the F. glaberrima unit was higher than other vegetation units. A similarity index analysis revealed that the F. sieboldiana unit (VU 9~11) was relatively homogeneous, and the M. bombycis unit (VU 1~5) and A. girta group (VU 7) were relatively heterogeneous. A detrended correspondence analysis determined that the distance between the statistical axes of the M. bombycis and F. glaberrima units was the greatest, which is consistent with the analysis of the similarity index. As a result of interspecific correlation of major woody plants, hydrophilic species were positively correlated, and a negative correlation was found between Q. mongolica and intolerant species such as P. densiflora and L. kaempferi.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.2
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• pp.130-138
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• 2011

This study was carried out to investigate growth characteristics and propagation methods of Clerodendron trichotomum for landscape uses. The results are obtained as follows: In the first place, Korean native C. trichotomum was printed in the "Enumeration of plants in Chosun" in 1937 by Tae Hyun Chung. C. trichotomum is a shrub with round shape. This is noted for its late summer flowers, showy fruit and malodorous foliage. White flowers in long-peduncled cymes bloom in the upper leaf axils from late summer into fall. Flowers are followed by small bright blue fruits, each subtended by a fleshy red calyx. C. trichotomum showed high seed germination rate and greater shoot length in plug box than in normal seeding bed. The rooting rate of C. trichotomum according to cutting date was highest on July 7. The optimum date for cutting was on July 7~10 when the shoots were more hardened. Soil acidity ranged from pH 4.58 to 5.52. The most effective method for rooting of C. trichotomum was treatment with 1,000 ppm IBA on July 7 cuttings, which showed rooting rate of over 90%. Korean native C. trichotomum was successfully propagated through soft cutting and seed.

• Journal of Apiculture
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• v.34 no.3
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• pp.245-254
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• 2019

We investigated the anti-tumor effects and molecular mechanism of Brazil, China and Korean regional propolis on HeLa ovarian cancer cell line. Each propolis extracts was prepared by ethanol extraction method. Cytotoxicity of propolis extracts was determinated by EZ-cytox cell viability assay. To necessity of anti-tumor effect and molecular mechanism of propolis, we must be adjusting propolis concentration. Due to 100 ㎍/mL of propolis extract were reduced cell viability to less than 50%, we adjusted all of propolis concentration to 100 ㎍/mL. By Western blotting analysis, we confirmed that anti-tumor mechanism of Brazil, China and Korea regional propolis has significantly difference. All of propolis was activated apoptosis related molecules such as PARP, caspase-3. However, cell proliferation signaling molecules including Akt1, ERK and Bcl-2 were reduced the protein expression level. Especially, the expression of tumor suppressor protein p53 was significantly increased in propolis-treated group such as Gyeonggi, Chungbuk, Chungnam, Jeonbuk, Gyeongnam and China. The phosphorylation of Bax which as apoptosis indicator was appeared in propolis-treated group such as Gyeonggi, Gangwon, Chungnam, Gyeongbuk, China. In this results showed that the regional propolis has completely different mechanism in anti-tumor. Thus, propolis extracts may be useful source of functional materials on anti-cancer and it will be able to choose the suitable propolis for cancer therapy by analyzing individual characteristics.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.374-390
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• 2021

Growth and yield of field vegetable crops would be affected by climate conditions, which cause a relatively large fluctuation in crop production and consumer price over years. The yield prediction system for these crops would support decision-making on policies to manage supply and demands. The objectives of this study were to compile literatures related to onion and garlic and to perform data-mining analysis, which would shed lights on the development of crop models for these major field vegetable crops in Korea. The literatures on crop growth and yield were collected from the databases operated by Research Information Sharing Service, National Science & Technology Information Service and SCOPUS. The keywords were chosen to retrieve research outcomes related to crop growth and yield of onion and garlic. These literatures were analyzed using text mining approaches including word cloud and semantic networks. It was found that the number of publications was considerably less for the field vegetable crops compared with rice. Still, specific patterns between previous research outcomes were identified using the text mining methods. For example, climate change and remote sensing were major topics of interest for growth and yield of onion and garlic. The impact of temperature and irrigation on crop growth was also assessed in the previous studies. It was also found that yield of onion and garlic would be affected by both environment and crop management conditions including sowing time, variety, seed treatment method, irrigation interval, fertilization amount and fertilizer composition. For meteorological conditions, temperature, precipitation, solar radiation and humidity were found to be the major factors in the literatures. These indicate that crop models need to take into account both environmental and crop management practices for reliable prediction of crop yield.