• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.106-115
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• 2011

The aim of this study is to assess the importance of ballast water discharge as a vector for the introduction of exotic species into Pusan and Daesan Ports, Korea. We also examined to understand the impacts of environmental factors on the survival success of introduced species by ship's ballast water in laboratory experiments. Seven ship's ballast water originated from the coastal water of China (Taicang, Ningbo and Jinshan), Japan (Tokuyama, Moji and Akita), and Singapore. According to PCA (principal components analysis) analysis, environmental factor in the each ballast and shipside waters were different by bioregion. Based on cluster analysis, the phytoplankton community structures were distinguished for ballast water origin. Most of the major taxonomic groups were diatoms and, the others were dinoflagellate, silcoflagellate and several fresh-waters species. In particular, species number and standing crops of phytoplankton in the ballast tanks decreased with the increasing age ofballast water(r = -0.35 for standing crop; r = -0.63 for species number). In the laboratory study, although phytoplankton in ballast water treatment did not survive even in optimal temperature, the in vivo fluorescence of phytoplankton viability increased under the nutrient typical of shipside water and F/2 medium at $15^{\circ}C$ and $20^{\circ}C$. The diatoms species such as Skeletonema costatum and Thalassiosira pseudonana in ballast water were successfully regrown. On the salinity gradient experiments for Shui Shan (2) vessel, several freshwater species, brackish and marine species were successfully adapted. Of these, S.costatum was able to tolerate a wide range of salinities (10 to 30 psu) and its species-specific viability was suitable for colonization.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.909-918
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• 2009

As a part of dissolved organic matter, dissolved organic carbon (DOC) or biodegradable DOC (BDOC) fraction in particular is one of important issues in water treatment. Due to role as a nutrient source for bacteria, BDOC, therefore, may cause regrowth problems in water distribution system. The main objectives of this study were to investigate the possibility to minimize the concentration of BDOC in advance water treatment process. DOC in water is fractionized into four fractions such as AnBDOC (adsorbable and non-biodegradable DOC) which possesses adsorption properties but no biodegradation ability; nABDOC (biodegradable and non-adsorbable DOC) which has biodegradation properties but no adsorption ability; ABDOC (adsorbable and biodegradable DOC) which has adsorption properties and biodegradable characteristic; and non-removal DOC (nAnBDOC) which do not have either adsorbability or biodegradability. BAC process was effective for adsorbable DOC (AnBDOC+ABDOC) removal. However, in some cases, the removal ratio of adsorbable DOC was not sufficient. BDOC removal rate is very low or irremovable. Thus, for the control of residual DOC, it is necessary to change the operation condition by BAC process. From the analysis results of DOC fractions, water treatment processes appeared to be effective because it could grasp a remarkable amount of biodegradable, adsorbable and non-removal DOC. The concentration of AOX in non-prechlorination process was reduced from 7.1 ${\mu}g$/L to 0.51 ${\mu}g$/L in BAC process followed by ozonation.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.1-11
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• 1987

This study was conducted to evaluate the effect of several fungicides and growth regulators on rice seedling growth and damping-off in seedling boxes for machine transplanting. Fungicide treated plots were better seedling growth, shoot regrowth, rooting ability, change of moisture content than those of nontreated plot. Metalaxyl application of Samgangbyeo and SF8002 application of Nagdongdyeo apparently increased plant height, length of the third leaf and fourth leaf. And metaiaxyl application highly increased dry weight. Fungicide treated plots were highly effective in reducing the incidence of damping-off. Benzyladenine application of Samgangbye and $GA_3$ application of Nagdongbyeo apprently increased plant height. But ABA application highly decreased plant height. ABA application and aCE application resulted in highly increased rooting ability. Fungicide and $GA_3$ treated plots, Metalaxyl and growth regulator treated plots resulted in highly increased plant height. I soprothiolane and growth regulator treated plots resulted in decreased plant height. Dachigaren and lAA treated plot apprently increased dry weight and shoot dry weight/plant height. Fungicide and growth regulator treated plots were highly effective in reducing the incidence of damping-off.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.328-333
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• 1983

Due to fast industrialization and reduced agricultural population, there has been increased farm mechanization to reduce the labor requirement. In rice production, mechanical transplanting has been increasingly popular due to the heavy labor requirement in hand transplanting and development of convenient transplanters. For mechanical transplanting, rice seedlings is grown in boxes with limited soils under super dense population, thus short period of exposure to unfavorable temperature and poor water management would cause severe damage to rice seedlings such as seedling damping off and the similar physiological disorders. Several chemicals were evaluated for their effectiveness to control the disease and disorders, and other effects as plant growth stimulants. 3-hydroxy-5-methylisoxazole-a soil fungicide, Metalozyl-a fungicide which controls mildew, SF 8002-the composite of above two chemicals, and Isoprothiolane-a fungicide which controls rice blast were found to be effective controling seedling damping off and similar physiological disorders, and improvement of physiological characteristics of the seedlings such as the amount of bleeding sap, rooting ability, negative geotrophism, and regrowth after cutting. The results indicated that the chemicals will be very effective raising healthy seedlings even under unfavorable environments by the improvement of physiological activities of seedlings and preventing seedling damping off and the similar physiological disorders.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.3
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• pp.199-204
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• 2010

A new tall fescue variety (Festuca arundinacea Schreb.) named "Greenmaster" was developed by the National Institute of Animal Science, RDA, at Suwon from 1999 to 2007. For synthetic seed production of this new variety, 5 superior clones, EFa9111, EFa9122, EFa9211, EFa9225, and EFa9234 were selected and polycrossed. The agronomic growth characteristics and forage production capability of the seeds were studied at Suwon from 2003 to 2004, and regional trials were conducted in Suwon, Pyungchang, Jeju, and Ikcsan from 2005 to 2007. Greenmaster showed enhanced winter hardiness, disease resistance, and regrowth ability as compared to Fawn. The dry matter yield of Greenmaster was 11% higher as 19,156 kg/ha than that of Fawn. However, the nutritive value of both varieties was similar.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.26-30
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• 2015

A new tall fescue variety (Festuca arundinacea Schreb.) named 'Greenmaster2ho' was developed by the National Institute of Animal Science, Rural Development Administration, in Cheonan, Korea from 2010 to 2014. For the synthetic seed production of this new variety, 5 superior clones were selected and polycrossed: 09XFa02, 09XFa03, 09XFa11, 09XFa13, and 09XFa14. The agronomic growth characteristics and forage production capability of the seeds were studied at Cheonan from 2010 onward, and regional trials were conducted in Cheonan, Hoengseong, Jeju, and Jinju from 2012 to 2014. Greenmaster2ho showed resistance to disease, persistence, and regrowth ability that were all enhanced when compared with Fawn. At 15,119 kg/ha, the dry matter (DM) yield of Greenmaster2ho was 29% higher than that of Fawn, but the nutritive value of both varieties as forage was similar. This study aimed to make a contribution to the vitalization of the Korean grassland industry by developing a new tall fescue variety with excellent environmental adaptability.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.61-78
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• 1997

PDGF-BB has been recognized as a highly potential growth factor for guided tissue regeneration in periodontal defect. This study carried out histologic and histometric evaluation of $200ng/cm^2$ PDGF-BB loaded bioresorbable membrane made from polyglycolic and polylactic acid. It was tested for its biocompatibility, ability to prevent epithelial downgrowth and amount of periodontal regeneration. Without membrane and PDGF-BB unloaded bioresorbable membrane were used as control. Healthy six beagle dogs were used. Each dog was anesthetized and buccal flaps were reflected in the mandibular and maxillary premolar areas. Buccal alveolar bone between the mesiobuccal and distobuccal line angles was surgically removed on the lower 2nd and 4th premolar in mandible, 2nd premolar in maxilla, to a level 4mm apical to the cementoenamel junction with creating a Class II buccal furcation defect for available space. Care was taken not to remove the root cementum layer and rubber impression materials were placed over each surgically created defect. Flaps were repositioned and sutured. Reconstructive surgery was performed 1 month after defect preparation. PDGF-BB loaded membranes and controls were randomly placed on maxillary 2nd premolars and mandibular 2nd and 4th premolars. Plaque control regimen was instituted with daily brushing with a 0.1% chlorhexidine digluconate during experimental periods. The animals were sacrificed 2 and 5 weeks after surgery and undecalcified specimens were prepared for histologic evaluation. The degree of coronal regrowth of new bone, new cementum and the amonut of new bone areas formed on the defected area of the PDGF-BB loaded membrnae turned superior to without membrane and drug unloaded membrane. Experimental membrane could prevent the epithelial downgrowth irrespective of drug loaded or not and showed good biocompatiblity, These results implicated that PDGF-BB loaded bioresorbable membrane could be highly useful tool for guided tissue regeneration of periodontal defects.