• The Korean Journal of Ecology
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• v.21 no.4
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• pp.337-344
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• 1998

To select tolerant species among the Korean major woody plants for restoring disturbed ecosystems by air and soil pollution, we transplanted the seedlings of 56 species in control and polluted sites within Yeocheon industrial complex area, and compared their aboveground growth characteristics such as total branch length, total leaf weight, and maximum photozynthetic rate. Tolerant species growting better in polluted site than in control site was Quercus variabilis, Pinus thunbergii, Q. aliena, P. densiflora, Styrax japonica, Alnus firma, Celtis sinensis, Elaeagnus umbellata, Q. serrata, japonica, Sorbus alnifolia, and Q. acutissimia in local tree occuring within polluted area group (80%), Ailanthus altissima in street tree group (20%), Populus tomentiglandulosa and A. hirsuta var. sibirica in fast growing tree group (50%), Acer ginala and Abies holophylla in late successional tree group (20%), Betulla platyphylla var. japonica, Acer truncatum, A. palmatum, Syringa dilatata, and Rosa multifora in garden tree group (38%), and Q. rubura, and Robinia pseudoacacia in foreign restoring tree group (20%), respectively. The remaining plant species, 37 species (57% of total species), were classified into sensitive species to pollution. Those tolerant species can be utilized for restoration of the degraded ecosystem in this polluted area.

• Archives of Craniofacial Surgery
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• v.19 no.2
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• pp.143-147
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• 2018

We present a patient who showed a sterile abscess after facial bone fixation with bioabsorbable plates and screws. He had zygomaticomaxillary complex and periorbital fracture due to falling down. The displaced bones were treated by open reduction and internal fixation successfully using bioabsorbable plate system. However, at postoperative 11 months, abrupt painless swelling was noted on the previous operation sites, left lateral eyebrow and lower eyelid. By surgical exploration, pus-like discharge and degraded materials were observed and debrided. The pathologic analysis revealed foreign body reaction with sterile abscess. This complication followed by bioabsorbable device implantation on maxillofacial bone surgery has been rarely reported in which we call attention to the maxillofacial plastic surgeons.

• Archives of Plastic Surgery
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• v.47 no.4
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• pp.297-300
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• 2020

Hyaluronidase, an enzyme that breaks down hyaluronic acid, has long been used to increase the absorption of drugs into tissue and to reduce tissue damage in cases of extravasation of a drug. With the increasing popularity of hyaluronic acid filler, hyaluronidase has become an essential drug for the correction of complications and unsatisfactory results after filler injection. For this reason, when performing procedures using hyaluronic acid filler, a sufficient knowledge of hyaluronidase is required. In order for hyaluronidase to dissolve a hyaluronic acid filler, it must interact with its binding sites within the hyaluronic acid. The reaction of a filler to hyaluronidase depends on the hyaluronic acid concentration, the number of crosslinks, and the form of the filler. Hyaluronidase is rapidly degraded and deactivated in the body. Therefore, in order to dissolve a hyaluronic acid filler, a sufficient amount of hyaluronidase must be injected close to the filler. If the filler is placed subcutaneously, injection of hyaluronidase into the filler itself may help, but if the filler is placed within a blood vessel, it is sufficient to inject hyaluronidase in the vicinity of the vessel, instead of into the filler itself. Allergic reactions are a common side effect of hyaluronidase. Most allergic reactions to hyaluronidase are local, but systemic reactions may occur in infrequent cases. Since most allergic responses to hyaluronidase are immediate hypersensitivity reactions, skin tests are recommended before use. However, some patients experience delayed allergic reactions, which skin tests may not predict.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.516-523
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• 2006

Marginal soils such as BRlS (Beach Ridges Interspersed with Swales) soils and ex-tin mining land make up approximately 0.5 million ha or about 2% of Malaysia's land area. In the coastal areas of the east coast of Peninsular Malaysia impoverished sandy BRIS dominates the landscape with most lying idle as there is no national management plan for their utilization. A field study was carried out to see whether mycorrhizal application had any effect on the growth of three exotic Acacia spp., i.e. Acacia auriculiformis, A. mangium and Acacia hybrid (A. auriculiformis ${\times}$ A. mangium) on BRIS soils. Two types of mycorrhizal inoculum, namely, a commercially available arbuscular mycorrhizal inoculum marketed as $MycoGold^{TM}$ and an indigenous ectomycorrhizal Tomentella sp. inoculum were tested. In the initial six months, height growth of all three tree species inoculated with the arbuscular mycorrhizal inoculum was significantly improved compared to the ectomycorrhizal inoculated and uninoculated control plants. The mycorrhizal effect was not evident thereafter and repeated application of the arbuscular mycorrhizal inoculum may be necessary for continued growth enhancement. Of the three species, A. mangium had the highest relative height growth rate over the 24 months on BRlS soils.

• Progress in Superconductivity and Cryogenics
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• v.6 no.4
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• pp.9-12
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• 2004

We report a successful fabrication of high-$J_C$ $NdBa_2Cu_3O_{7-{\delta}}$ (NdBCO) films on (100) $SrTiO_3$ substrates by pulsed laser deposition (PLD) in high oxygen pressures ranging from 400 to 800 mTorr. Fabricated NdBCO films exhibited only c-axis orientation, good out-of-plane and in-plane textures, and also excellent superconducting properties, including critical temperature ($T_C$) and critical current density ($J_C$) of above 90 K and the highest of $3.1MA/cm^2$ at 77 K in self-field, implying that NdBCO is a perspective alternative to YBCO for coated conductor. In low oxygen pressures ranging from 100 to 200 mTorr, however, the films showed a-, c-mixed orientation and degraded $T_{C,zero}$ values due to the formation of $Nd_{1+x}Ba_{2-x}Cu_3O_{7-{\delta}}$-type solid solutions with an excessive substitution of $Nd^{3+}$ ions for the $Ba^{2+}$ sites.

• Geomechanics and Engineering
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• v.35 no.2
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• pp.109-119
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• 2023

Ground subsidence in urban areas due to excessive development and degraded underground facilities is a serious problem. Geophysical surveys have been conducted to estimate the distribution and scale of cavities and subsidence. In this study, electrical resistivity tomography (ERT) was performed near an area of road subsidence in an urban area. The subsidence arose due to groundwater leakage that carried soil into a neighboring excavation site. The ERT survey line was located between the main subsidence area and an excavation site. Because ERT data are affected by rapid topographic changes and surrounding structures, the influence of the excavation site on the data was analyzed through field-scale numerical modeling. The effect of an excavation should be considered when interpreting ERT data because it can lead to wrong anomalous results. A method for performing 2D inversion after correcting resistivity data for the effect of the excavation site was proposed. This method was initially tested using a field-scale numerical model that included the excavation site and subsurface anomaly, which was a loosened zone, and was then applied to field data. In addition, ERT data were interpreted using an existing in-house 3D algorithm, which considered the effect of excavation sites. The inversion results demonstrated that conductive anomalies in the loosened zone were greater compared to the inversion that did not consider the effects of excavation.

• Journal of Life Science
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• v.24 no.2
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• pp.128-136
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• 2014

Alginates are linear acidic polysaccharides composed with (1-4)-linked ${\alpha}$-L-guluronic acid and ${\beta}$-Dmannuronic acid. Alginate can be degraded by diverse alginate lyases, which cleave the alginate using a ${\beta}$-elimination reaction and produce unsaturated uronate oligomers. A gene for a polyMG-specific alginate lyase possessing a novel structure was previously identified and cloned from Stenotrophomonas maltophilia KJ-2. Homology modeling of KJ-2 polyMG-specific alginate lyase showed it belongs to the PL6 family, whereas three Azotobacter vinelandii polyMG lyases belong to the PL7 family of polysaccharide lyases. From $^1H$-NMR spectra data, KJ-2 polyMG lyase preferably degraded the M-${\beta}$(1-4)-G glycosidic bond than the G-${\alpha}$(1-4)-M glycosidic bond. Seventeen mutants were made by site-directed mutagenesis, and alginate lyase activity was analyzed. Lys220Ala, Arg241Ala, Arg241Lys, and Arg265Ala lost alginate lyase activity completely. Arg155Ala, Gly303Glu, and Tyr304Phe also lost the activity by 60.7-80.1%. These results show that Arg155, Lys220, Arg241, Arg265, Gly303, and Tyr304 are important residues for catalytic activity and substrate binding.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1851-1859
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• 2000

Crude oil-degrading bacteria were isolated from the sites contaminated by oil products. The isolates were identified as Acinetobacter sp. A132, Pseudomonas putida A422, Pseudomonas aeruginosa F721, F722, and Xanthomonas maltophilia B823. The results of investigation on the degradability of crude oil indicated that the strain A132 had the highest rate of $6.04g/L{\cdot}day$. Also, the strain A132 and F722 almost degraded each of n-alkane compounds between $nC_{10}$ and $nC_{32}$. The strain A422 degraded benzene and xylene but not n-alkane. The strain B823 grew somewhat in crude oil but did not entirely degrade other substrates used in this study. The results of the GC/FID analysis on the degradability of the mixed n-alkane compounds showed that the strain F722 could degrade 100% of the compounds with $nC_7{\sim}nC_{10}$ and more than 80% of those with $nC_{11}{\sim}nC_{24}$.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.265-272
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• 2017

Some bacteria with different mechanisms for hydrocarbon degradation were isolated from oil-contaminated soils in Korea. Isolate Acinetobacter calcoaceticus SL1 showed biosurfactant- producing activity in oil-spreading test, and it exhibited a good emulsifying activity of 43.6 and 54.5% for diesel oil and n-hexane, respectively. It also has high cell surface hydrophobicity which can make it easily attaches to hydrocarbons and degrade them. It degraded 100% of 1,000 mg/L of n-octadecane and naphthalene, respectively in 3 days, 72.3% of 1,000 mg/L diesel oil in 7 days and 78.0% of 10,000 mg/L diesel oil in oil-contaminated soil during 28 days. Isolated strains Bacillus amyloliquefaciens S10 and B. subtilis GO9 can produce biosurfactant and formed 6.34 and 2.5 cm diameter of clear zones, respectively in oil-spreading test. Surface tension of their culture supernatant reduced from 74.6 to 34.4 and 33.3 mN/m, respectively during incubation, and critical micelle concentrations of culture supernatants were 2.0 and 5.9%, respectively. Consortium of A. calcoaceticus SL1 and B. amyloliquefaciens S10 degraded 77.8% of 10,000 mg/L diesel oil in 3 days, which indicated more efficient oil degradation than that by A. calcoaceticus SL1 alone. If these bacteria were applied together as a consortium to oil-contaminated sites, they may show a high removal rate of petroleum hydrocarbons.

• Macromolecular Research
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• v.17 no.10
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• pp.734-738
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• 2009

Biodegradable, pH-sensitive, glycol chitosan (GC) hydrogels were prepared using divinyl adipate (DVA) as a crosslinker and acetic acid as a catalyst. DVA has highly reactive double vinyl ester groups and GC contains a high density of hydroxyl groups, with two in every glucosamine unit. The transesterification reaction between vinyl esters and hydroxyl groups produced crosslinked GC hydrogels. The initial crosslinking reaction was monitored by measuring the viscosity of the reaction mixture. When DVA was added to the GC solution and heated to $50^{\circ}C$, the viscosity of the GC solution gradually increased, implying a crosslinking reaction and hydrogel formation. A new peak from the ester group was observed in the FTIR spectra of the GC hydrogels, confirming the crosslinking reaction. The synthesized GC hydrogel showed pH-dependent water absorbency, mainly due to the presence of amine groups ($-NH_2$) at the C-2 position of the glucosamine unit of GC. The water absorbency greatly increased at acidic pH and slightly decreased at alkaline pH. The GC hydrogel gradually degraded in $37^{\circ}C$ water due to hydrolysis of the ester bonds, which were intermolecular crosslinking sites. A red dye, 5-carboxyltetramethyl-rhodamine (CTMR), was entrapped in the GC hydrogels as a model compound. CTMR was released from GC hydrogels in two steps: an initial burst release mainly due to desorption and diffusion, and a second sustained release possibly due to gradual degradation.