• Journal of Chest Surgery
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• v.36 no.12
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• pp.921-927
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• 2003

Arterial switch operation (ASO) has been the most effective surgical option for transposition of the great arteries. But, the inappropriate dilation of the neoaortic root has been reported and its effect on neoaortic valve function and growth of aorta has not been well documented. Material and Method: Forty-eight patients who underwent cardiac catheterization during follow up after arterial switch operation were included in this study. Arterial switch operation was performed at a median age of 18 days (range 1∼211 days). Preoperative cardiac catheterization was performed in 26 patients and postoperative catheterization was performed in all patients at 15.8$\pm$9.6 months after ASO. Postoperative ratios of the diameters of neoaortic annulus, root and aortic anastomosis against the descending aorta were compared to the size of preoperative pulmonary annular, root and sinotubular junction. Preoperative and operative parameters were analyzed for the risk factors of neoaortic insufficiency. Result: There were two clinically significant neoaortic insufficiencies (grade$\geq$II/IV) during follow up, one of which required aortic valve replacement. Another patient required reoperation due to aortic stenosis on the anastomosis site. Post-operatively, neoaortic annulus/DA ratio increased from 1.33$\pm$0.28 to 1.52$\pm$.033 (p=0.01) and neoaortic root/DA ratio increased form 2.02$\pm$0.40 to 2.56$\pm$0.38 (p<0.0001). However, the aortic anastomosis/DA ratio showed no statistically significant difference (p=0.06). There was no statistically significant correlation between the occurrence of neoaortic insufficiency and neoaortic annulus/DA ratio and neoaortic root/DA ratio. Non-neonatal repair (age>30days) (p=0.02), preopeative native pulmonaic valve stenosis (p=0.01), and bisuspid pulmonic valve (p=0.03) were the risk factors for neoaortic insufficiency in univariate risk factor analysis. Conclusion: After ASO, aortic anastomosis site showed normal growth pattern proportional to the descending aorta, but neoaortic valve annulus and root were disproportionally dilated. Significant neoaortic valve insufficiency rarely developed after ASO and neoaortic annulus and root size do not correlate with the presence of postoperative neoarotic insufficiency. ASO after neonatal period, preoperative native pulmonary valve stenosis, and bicuspid native pulmonic valve are risk factors for the development of neoaortic insufficiency.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.6
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• pp.86-97
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• 2015

"The Jayeon Madang Development Project("JMDP")" is a project being promoted by the Ministry of Environment to create a cultural space and a natural rest area within the city. Abuksan, located at Abuksan in Gyeongsangnam-do Miryang-si Naeil-dong, has suffered a substantial amount of environmental degradation over time, so the need for ecological restoration made it a natural choice for the location of the JMDP's site. The purpose of this study is to examine ecological restoration design strategies used in Abuksan as part of the JMDP using system dynamics. The national archery center, hole, and arable land sites are key restoration areas in Abuksan that have faced with ecological problems. In this study, we identified the status of each site, determined key strategies being implemented, and designed based on the strategies implemented up to this point for solving problems associated with each sites through the use of causal loop diagrams. The results of the causal loop diagram analysis are as follows. The national archery center site was designed around strategies including planting green manure crops and introducing hugelkultur to reduce soil acidification and green network degradation. The hole site was designed as a constructed wetland based on the emergence of hygropreference vegetation, hydrated by rainwater collected at the bottom of hole, ecological and cultural benefits of such an environment. The arable land site restoration design was built around planting native vegetation on one part of the arable land site after soil quality improved and around restoration of grassland and a dry wetland on the other part of the site to reduce soil acidification, erosion, and green network degradation. This study is a significant attempt to apply principles of system dynamics to ecological restoration by providing the design strategies using comprehension of some problems in the ecosystem feedback loops, which has not been used before in general design processes for ecological restoration.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.5
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• pp.1-13
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• 2017

This study was intended to provide management directions through the provision of tree spatial information as basic data for the preservation of Gyerim(legal historical site), which is located in Gyeongju city, Gyeonsangnam-do, Korea. As a result of the survey of the entire forest, there are a total of 25 species and 510 individuals growing trees. Of these species, 14 species are native and 14 are introduced species. Apart from Sophora japonica, Zelkova serrata, Celtis sinensis, most of the introduced species were adopted without historical basis after designation as a historical site. By a ratio of 36% to introduced species(including 3% of naturalized species; Ailanthus altissima), the historical heritage was significantly damaged. Gyerim, which has over 2,000 years of history, has a total 15 individuals(2.9%) large trees(over 100cm DBH). Ten of these are Salix glandulosa, and in the past, most of this area was considered a Salix glandulosa forest. Currently, however, there are many small trees(under 20cm DBH) for the next generation of growth and the Salix glandulosa forest will continue to decline. Furthermore, most small trees were afforested, so the historicity and place features as a mythological forest will quickly fade.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.496-503
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• 2021

Pinus densiflora is an essential tree species native to the Republic of Korea (ROK) and covers most of the total natural forest areas in the ROK. This study was conducted to understand the site characteristics and stand structure of P. densiflora forests distributed at sites where P. densiflora covered over 50% of the stand basal area during the 7th National Forest Inventory (NFI) period from 2016 to 2020. P. densiflora dominated 3,665 circular sample plots (400 m²). P. densiflora forests predominated at elevations less than 600 m above sea level (a.s.l). However, most P. densiflora forests were distributed at the slopes facing south and west over 800 m a.s.l. At altitudes below 800 m, they were distributed at all slopes but dominated at the southern and western slopes. P. densiflora grew mainly in the soils of sandy loam, loam, or silt loam with relative infertility. Dominant tree species distributed with P. densiflora were Quercus mongolica, Q. variabilis, Q. serrata, Prunus serrulata var. pubescens and Castanea crenata by the descending order. P. densiflora, P. thunbergii, and P. rigida were grown in large DBH classes, Quercus species and Fraxinus rhynchophylla in middle DBH classes, while Juniperus rigida and Styrax japonicus in small DBH classes. Dominant tree species distributed mainly at the lower layer of P. densiflora stands were Rhododendron mucronulatum, Q. serrata, Lindera obtusiloba, Fraxinus sieboldiana, Toxicodendron trichocarpum and Rhododendron schlippenbachii by the descending order.

• Journal of Veterinary Clinics
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• v.30 no.1
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• pp.66-70
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• 2013

This report compared paramedian and flank approaches for the effective removal of abdominal unilateral cryptorchidism in calves. Two Korean native calves of approximately 300 kg in body weight, which had undergone the removal of a testis from the scrotum, were diagnosed as having abdominal unilateral (left) cryptorchidism by rectal palpation. One calf was administered with xylazine (0.2 mg/kg, IV) and was restrained in the dorsal recumbency position on the ground of barn for the paramedian approach, while the other calf was sedated with xylazine (0.03 mg/kg, IV) and restrained in the standing position for a flank approach. For the two calves, 2% lidocaine was administered by local infiltration, along the proposed incision line. Following incisions of the skin, muscle and peritoneum, the testis, which was located between the left kidney and inguinal canal, was grasped, exteriorized out of the abdominal cavity and detached from the gubernaculum testis. Then spermatic cord was ligated and cut. Finally, the testis was removed. An assistant was required to restraint a calf in dorsal recumbency for paramedian approach, and cryptorchidectomy was carried out with operator in a rather uncomfortable squatting posture, while restraint was rather simple and cryptorchidectomy was proceeded with operator in a standing posture where the flank approach was taken. During surgery, the gubernaculum testis was more strained during pulling the testis in the flank approach than in the paramedian approach, as the distance between incision site and the gubernaculum testis was greater in the flank approach than that in the paramedian approach. On the other hand, intra-abdominal pressure was greater in the paramedian approach than in the flank approach during surgery. The elapsed time between restraint and the end of surgery was 10 min shorter where the flank approach (35 min) was taken, than where the paramedian approach (45 min) was taken. In conclusion, this case study demonstrated that the flank approach might be more convenient than the paramedian approach for abdominal unilateral cryptorchidectomy in calves.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.313-319
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• 1995

The involvement of the cell-wall degrading enzymes in Rhizobium has long been an unsolved question about the infection process in the formation of root nodule. To assess the contribution of the cellulase to the nodulation of rhzobia, here we report the production of cellulase from R. meliloti TAL1372 which degrade carboxymethylcellulose (CMC) model substrate with CMC-plate method. We constructed a genomic library by cloning Sau3A-digested genomic DNA from R. meliloti TAL1372 into the BamHI site of the cosmid vector pLAFR3. Out of more than one thousand transductants of E. coli, one clone (pRC8-71) had CM-cellulase activity and contained pLAFR3 cosmid with 30 kb insert of R. meliloti DNA The product of CM-cellulase gene was analyzed by native PAGE. About 45 kD protein was considered to be a product of the gene. Tn5 mutagenesis reveals that the structural gene located in a ca. 3 kb KpnI fragment. The cellulase-minus mutants of R. meliloti TAL1372 were obtained by Tn5 mutagenesis of pRC8-71 and marker exchange techniques. Analyses of the nodulation ability of these Tn5 mutants showed that the CM-cellulase gene of R. meliloti TAL1372 may be involved in early nodulation development on alfalfa (Medicago satiua).

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.302-317
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• 2010

In this study, not only to present the management plan but also to verify the effectiveness for a area of improving the landscape and the area of creating the base of bio-inhabitation in Tancheon stream concrete embankment where were practised the vegetation-mat measures for greening via monitoring i.e. restoration progress. The results of monitoring, there were a total of 41 taxa, 18 families, 38 species, 3 varieties in 2006, moreover in the 2007, there were a total of 59 taxa, 19 families, 56 species, 3 varieties and in the period 2008, 64 taxa, 29 families, 59 species, 8 varieties. Therefore, these site has increased the plant spaces year by year. The distribution of vegetation characteristics shows that Miscanthus sacchariflorus and Pennisetum alopecuroides expands their influence in the area of applying the construction method. Those area appears a diversity of native species by the stream deposition at the flood. Thus, its condition is very soundly ecological health and eco-friend. At present, native species have been dominant, however, disturbed species and invasive species can be expected to increase dramatically in the future. Therefore, it is necessary to a long-range monitoring and management for maintaining an environmentally sound aquatic ecosystem. On this area refer to mix the river vegetation of primary succession and disturbed vegetation. For that reason, the method of constructing the vegetation-mat measures for greening in embankment does not need to remove the concrete and can install a coir-mat on the top. It leads to improve the landscape, moreover, it was analysed the such dramatic changes in the vegetation species richness by providing continuous the plant growth basis have a impact on in bio-diversity.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.84-101
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• 2004

This study presents an ecological management plan for wildbird habitat conservation, an nature-friendly enhancement of bio-diversity using the riverside of the Tancheon Ecosystem Conservation Area in Seoul by analyzing environmental and ecological characteristics. As a result of analyzing actual vegetation, vegetation type was classified into 34 types. Humulus japonicus association covers an area of 441,568.6㎡(31.44％), and Artemisia princeps var. orientalis association covers an area of 89,690.1㎡(6.39％). Sandy plain as valuable wildbird habitat covers an area of 89,965.9㎡(6.4％). 125 taxa including 34 families, 93 genera, 107 species, and 18 varieties were recorded and the number of naturalized plants were 41 taxa at the survey site. Total naturalized index(NI) and urbanized index(UI) were recorded as 32.8％, and 15.5％. As a result of analyzing the herb plants association structure by surveying 8 belt-transects, the humid native plants was dominant in the partially adjacent revetment edge and damp riverside. On the other hand, naturalized plants was so extensively dominant that it was necessary to establish an ecological management plan. The observed wildbirds belonged to 50 species, 6,118 individuals, and 7 restricted species by law, which were Accipiter gentilis, Falco tinnunculus, Buteo hemilasius, and Buteo buteo. Oriolus chinensis,Hirundo rustica, and Alcedo atthis. The ecological administration plan for Tancheon Ecosystem Conservation Area as follows: in ecological land-use planning, the conservation area(695,518.5㎡) has native woody and herb vegetation and sandy plain with water as an wildbird habitat. The restoration area(653,702.7㎡) has a naturalized plants distribution are with artificial revetment. The nature-friendly Riverside Area(55,414.9㎡) was an easily approached area with damaged riverside vegetation, and a safe area to wildbird habitat. In riverside restoration planning, the artificial riverside should be restored to its natural riverside vegetation, and the artificial embankment should be restored with edge shrubs for wildbird habitat or revegetated for natural riverside landscape. For naturalized plants management planning, we selected naturalized plant species to be weeded out, and suggested an application method for ecological management.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.200-207
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• 2009

In this study, the characterization of purified erythritol 4-phosphate dehydrogenase, key enzyme of erythritol biosynthesis, produced by Penicillium sp. KJ81 was investigated. Optimum production conditions of erythritol 4-phosphate dehydrogenase was 1 vvm areration, 200 rpm agitation, at $37^{\circ}C$ for 8 days in the medium containing 30% sucrose, 0.5% yeast extract, 0.5% $(NH_4)_2SO_4$, 0.1% $KH_2PO_4$, and 0.05%$MgCl_2$. Erythritol 4-phosphate dehydrogenase was purified through ultrafiltration and preparative gel electrophoresis from cell extract of Penicillium sp. KJ81. This enzyme was especially active on erythrose 4-phosphate with 1.07 mM of Km value. It gave a single band on native polyacrylamide gel electrophoresis and an isoelectric point of 4.6. The enzyme had an optimal activity at pH 7.0 and $30^{\circ}C$. It was stable between pH 4.0 and 9.0, and also below $30^{\circ}C$. The enzyme activity was completely inhibited by 1mM $Cu^{2+}$ and 1 mM $Zn^{2+}$, but was not significantly affected by other cations tested. This enzyme was inactivated by treatment of tyrosine specific reagent, iodine and tryptophan specific reagent, N-bromosuccinimide. The substrate of the enzyme, erythrose 4-phosphate showed protective effect on the inactivation of the enzyme by both reagents. These results suggest that tryptophan and tyrosine residues are probably located at or near active site of the enzyme.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.160-169
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• 2008

Bakcground: To treat anastomosis site stenosis and occlusion of the artificial vessels used in vascular surgery, tissue-engineered artificial vessels using autologous cells have been constructed. We developed artificial vessels using a polymer scaffold and autologous bone marrow cells and performed an in vivo evaluation. Material and Method: We manufactured a vascular scaffold using biodegradable PLCL (poly lactide-co-${\varepsilon}$-caprolactone) and PGA (poly glycolic acid) fibers. Then we seeded autologous bone marrow cells onto the scaffold. After implantation of the artificial vessel into the abdominal aorta, we performed an angiography 3 weeks after surgery. After the dogs were euthanized we retrieved the artificial vessels and performed histological analysis. Result: Among the six dogs, 2 dogs died of massive bleeding due to a crack in the vascular scaffold 10 days after the operation. The remaining four dogs lived for 3 weeks after the operation. In these dogs. the angiography revealed no stenosis or occlusion at 3 weeks after the operation. Gross examination revealed small thrombi on the inner surface of the vessels and the histological analysis showed three layers of vessel structure similar to the native vessel. Immunohistochemical analysis demonstrated regeneration of the endothelial and smooth muscle cell layers. Conclusion: A tissue engineered vascular graft was manufactured using a polymer scaffold and autologous bone marrow cells that had a structure similar to that of the native artery. Further research is needed to determine how to accommodate the aortic pressure.