• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.66-72
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• 1995

The rate of fixation of the components were evaluated in CCA-Type B and CCFZ-treated radiata pine sapwood by quantitative analysis of solution expressed from the treated wood. The leaching characteristics of radiata pine blocks treated with CCA-Type B and CCFZ were also evaluated by the AWPA standard leaching test. Both fixation and leaching charactersistics of CCA-Type B were compared with CCA-Type C treated wood samples. The rate of CCA-Type B fixation was a little faster than that of CCFZ. However, significant amounts of arsenic was unfixed in the CCA-Type B treated samples and consequently leached. These significant quantities of arsenic liberated from the CCA-Type B treated wood during service may pose some environmental concerns. Arsenic was no longer detectable from CCA-Type C treated samples when fixation was complete, even though the fixation of CCA-Type C was slower in some degree than CCA-Type B. In summary, it could be said that CCFZ was much safer preservative than CCA-Type B by the criterion based on the relative hazard assessed by absolute amount of unfixed element present in the treated wood. Also the decision that CCA preservative has to move from Type B to Type C should be made sooner or later for continuous use of CCA preservative in the future.

• Journal of the Korean Wood Science and Technology
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• v.29 no.1
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• pp.52-59
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• 2001

The fixation characteristics of CCA and CCFZ in Japanese red pine, Japanese larch, and ezo spruce sapwood were compared at various temperatures and fixation conditions (drying and nondrying fixation). Fixation was monitored by the rates of reduction of hexavalent chromium to trivalent one, and optimal fixation time was estimated based on the results. The rate of fixation was highly temperature dependent, and the fixation rate of treated wood conditioned under nondrying conditions was much more faster than that under drying conditions, especially when the moisture content of treated wood was below fiber saturation point. Preservative types affected fixation; CCA-Type B had the highest fixation rate, followed by CCA-Type C and then CCFZ. The differences in fixation rates of preservative components were also observed among wood species; Japanese red pine fixed the fastest, followed by Japanese larch and then ezo spruce. Time required to complete fixation according to the fixation temperature could be predicted successfully using the regression equations between the temperatures and fixation time, regardless of conditioning methods, preservative types, and wood species.

• Journal of the Korean Wood Science and Technology
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• v.20 no.1
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• pp.15-22
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• 1992

This study was performed to investigate the corrosion of metal fasteners in waterborne preservative-treated wood. Of all the metal tested, steel exhibited the greatest amount of corrosion across all preservatives and exposure conditions whereas stainless steel was totally inert. Galvanized steel corroded at a much lower rate compared to steel and the corrosion of brass was negligible. Among the preservatives, CCA-Type B was the most corrosive system tested. The sequence for the average corrosivity across all metals was: CCA-type B>CCA-Type C${\geq}$ACC${\geq}$CCA-Type A. Across all metals and retentions the salt formulations were more corrosive than the oxide and the corrosion was increased with the increse in the amount of preservative loadings. The amount of corrosion was also increased with the increase in exposure relative humidity (RH) across all metals and presevatives However, at the 60% RH exposure condition, the corrosion of metals was very negligible. Consequently, it can be concluded that across all metals oxide-type preservatives should be used to prevent the corrosion problem of metal fasteners in contact with treated wood and the use of steel nail preservative-treated wood should be avoided without distinction of end-use location, i.e., exterior or interior, and the use of stainless steel or at least brass nail in damp exterior condition was strongly recommended.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.33-38
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• 1995

The rates of fixation of CCA-Type B and CCFZ in blocks of radiata pine sapwood were compared at various temperatures and conditioning methods (drying and nondrying conditioning). Also the time required to proper fixation of preservative components in the treated wood was estimated. Fixation was monitored by the rates of depletion of free hexavalent chromium in the cell lumens in the teated blocks. The rate of preservative fixation in wood was highly temperature dependent. The fixation rate was considerably accelerated by means of heating and complete fixation of hexavalent chromium was achieved within about 12 hours by heating at $60^{\circ}C$. The moisture content of treated wood during fixation apparently played an important role in the fixation process. The fixation rate of treated wood conditioned in nondrying conditions was much more faster than that of treated wood conditioned in drying conditions. particularly when the moisture content of treated wood was below fiber saturation point. Time required to full fixation could be predicted successfully using the fixation temperatures applied since the correlation between the fixation temperature and the fixation time was excellent. regardless of conditioning methods.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.37-44
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• 2016

Several infectious agents are considered to be causes of cancer in human, mainly hepatitis B and C viruses, high-risk human pailloma viruses, Helicobacter pylori, Clonorchis sinensis, and Opisthorchis viverrini. Here we described the evident research and the association between Helicobacter spp. and biliary tract cancer particularly cholangiocarcinoma (CCA). Global epidemiological studies have suggested that Helicobacter spp. are possible risk factors for biliary tract diseases. Molecular studies support a linkage of Helicobacter spp. with CCA development. H. pylori, H. bilis, and H. hepaticus, are found in CCA, but the most common species are H. pylori and H. bilis. The type of CCA are associated with Helicobacter spp. include extrahepatic CCA, and common bile duct cancer. Up to the present, however, the results from different regions, materials and methods, sub-sites of cancer, and controls have not been consistent, thus introducing heterogeneity. Therefore, a comparison between co-Helicobacter spp.-CCA in the countries with low and high incident of CCA is required to settle the question. Furthermore, clarifying variation in the role of Helicobacter species in this CCA, including pathogenesis of CCA through enhanced biliary cell inflammation and proliferation, is necessary.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1158-1161
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• 2006

The toner type paper-like display (PLD) has been developed with two polymer particles having opposite polarity which is composed of polymer, colorant and external additives (nano-sized silica). Nano-sized silica with triboelectric charge was used for the charge control agent (CCA) and influenced on the electrostatic properties of the silica-coated polymer particles. The PLD cell using silica-coated particles (200 seconds) had shown a good white appearance and low driving voltage. The result could be explained in terms of the surface morphology and the cohesiveness depending on the silica coating time.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.130-149
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• 2017

The subalpine zone which is vulnerable to climate change could be functioning as a habitat for northern plant species especially in the Korean peninsula. In this study, classification of phytosociological community type and investigation on flora of vascular plants of Daecheongbong area in Mt. Seorak were carried out in order to provide a basic information for an ecological restoration and management of the vegetation through community ecological approach. Vegetation data were collected from 31 of quadrates from May to October, 2016. We analyzed vegetation types with phytosociological method, importance value with Curtis & McIntosh method, CCA using PC-ORD program tool, and flora of vascular plants. As a result, the forest vegetation was classified into Abies nephrolepis community. The community was divided 3 groups such as Pinus pumila group, Rhododendron brachycarpum group and Angelica decursiva group. Therefore, the vegetation had 3 kinds of units. The differential species group, it was classified into total of 7 species group units including Thuja koraiensis and Smilacina bicolor differential species group. The mean importance percentage (MIP) in VU 1 was shown Pinus koraiensis (24.1), A. nephrolepis (23.6) and Betula ermanii (10.5), and in VU 2, it was P. koraiensis (26.2), A. nephrolepis (20.8) and B. ermanii (10.5), and in VU 3, it was P. koraiensis (22.2), A. nephrolepis (16.4), B. ermanii (13.5) in the order, respectively. As for importance values of P. koraiensis and A. nephrolepis representative competition species, were different at each layers. The former (46.7) was higher than the latter (26.1) in tree layer, but the latter was higher than the former in subtree and, shrub and herb layers of VU 1. VU 2 and VU 3 also indicated the same tendency. P. pumila group and A. decursiva group were shown to have positive correlation with altitude and present species, respectively. The designated as the endemic plant was 11 taxa and, as the rare plant 24 taxa and 62.5% of vascular plant was northern plant species. It is necessary to continue further long-term monitoring of 3 vegetation units, IV of main competition species (P. koraiensis and A. nephrolepis) with stratum and main specific species (rare plants and endemic plants) considering vegetation science and, population and community ecology approaches.

• Journal of Acupuncture Research
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• v.25 no.5
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• pp.105-116
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• 2008

Objectives : The objective of this study is to investigate the suppressing effect of the cervi pantotrichum cornu pharmacopuncture on the expression of iNOS mRNA and production of NO in synoviocytes from artificially arthritis-induced mice. Methods : In vitro test, synoviocytes extracted from a knee joint of a mouse were cultivated, and the herbal extract of cervi pantotrichum cornu($0.4mg/m{\ell}$, $0.6mg/m{\ell}$, $0.8mg/m{\ell}$, and $1.0mg/m{\ell}$) was added into the wells of synoviocytes to suppress the expression of iNOS mRNA and production of NO. In vivo test, each ten mice were allocated into three groups; Normal group, CIA-elicitated group(CIA), and group treated with cervi pantotrichum cornu pharmacopuncture after CIA elicitation(CCA). The extract of cervi pantotrichum cornu was injected into the acupoint of $SP_{10}$ to observe the changes of foot thickness in mice and the suppression of MIF, TNF-$\alpha$, NF-${\kappa}B$ p65, and iNOS. Results : In vitro test, the expression of iNOS mRNA and production of NO were dose-dependently decreased in the wells of synoviocytes treated with PMA. In vivo test, the suppression of MIF, TNF-$\alpha$, NF-${\kappa}B$ p65, and iNOS was clearly shown in the pieces of the synovial joint treated with the extract of cervi pantotrichum cornu. The foot thickness also decreased dose-dependently. Conclusions : It is speculated that the cervi pantotrichum cornu pharmacopuncture can be applicable to the therapy of rheumatoid arthritis by suppressing the expression of iNOS mRNA and production of NO.

• Tuberculosis and Respiratory Diseases
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• v.60 no.2
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• pp.171-179
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• 2006

Background : Despite the emerging danger of MDR-TB to human beings, there have only been a limited number of drugs developed to treat MDR-TB since 1970. This study investigated the cross-resistance rate between rifampicin (RFP) and rifabutin (RBU) in order to determine the efficacy of rifabutin in treating MDR-TB. In addition, the results of rifabutin were correlated with the rpoB mutations, which are believed to be markers for MDR-TB and RFP resistance. Methods : The MICs of RBU were tested against 126 clinical isolates of MDR-TB submitted to the clinical laboratory of National Masan TB Hospital in 2004. Five different concentrations ($10-160{\mu}g/ml$) were used for the MICs. The detection of the rpoB mutations was performed using a RFP resistance detection kit with a line probe assay(LiPA), which contains the oligonucleotide probes for 5 wide type and 3 specific mutations (513CCA, 516GTC, and 531TTG) The rpoB mutation was determined by direct sequencing. Results : The rate of cross-resistance between RFP and RBU was 70.5%(74/105) at $20{\mu}g/ml$ RBU(ed note: How much RFP?) Most mutations (86.3%) occurred in the 524~534 codons. The His526Gln, His526Leu, Leu533Pro, Gln513Glu, and Leu511Pro mutations(Ed note: Is this correct?) were associated with the susceptibilty to RBU. Conclusion : Based on the cross-resistance rate between RFP and RBU, RBU may be used effectively in some MDR-TB patients. Therefore, a conventional drug susceptibility test for RBU and a determination of the critical concentration are needed. However, rpoB gene mutation test may be have limited clinical applications in detecting RBU resistance.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.275-287
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• 2017

The purpose of this study was to analyze forest vegetation type classification and relationships between the type and environment factor in Mt. Dutasan. Data were collected by total of forty six plots using Z-M phytosociological method from June to October, 2016, and analyzed by vegetation classification, canopy layer structure and relationships between vegetation unit and environment factor using coincidence methods. As a result of vegetation type classification, Quercus mongolica community group was classified at a top level of vegetation hierarchy that was classified into Rhododendron schlippenbachii community and Betula costata community. R. schlippenbachii community was divided into Lychnis cognata group and R. schlippenbachii typical group. L. cognata group was subdivided into Veratrum oxysepalum subgroup and L. cognata typical subgroup. B. costata community was divided into Fraxinus mandshurica group and Betula schmidtii group. F. mandshurica group was subdivided into Weigela subsessilis subgroup and Cimicifuga heracleifolia subgroup. Therefore the forest vegetation was composed of six vegetation units with two kinds of bisected species groups and fourteen species groups. As the result of an analysis of canopy layer structure, there were two kinds of structures with monotonous structures V. oxysepalum subgroup (vegetation units 1), L. cognata typical subgroup (vegetation units 2), W. subsessilis subgroup (vegetation units 4) and complicated structures R. schlippenbachii typical group (vegetation units 3), C. heracleifolia subgroup (vegetation units 5), Betula schmidtii group (vegetation units 6). The vertical layer structure of vegetation unit 5 was the most developed and vegetation unit 6 had the lowest coverage of herb layer. According to the correlation between vegetation unit and environmental factor, R. schlippenbachii community (vegetation units 1~3) and B. costata community (vegetation units 4~6) were classified based on 1,100 m of altitude, middle slope, twenty of slope degree, twenty percents of bare rock and thirty centimeters of DBH in tree layer. R. schlippenbachii community (vegetation units 1~3) showed positive correlation with altitude, topography and B. costata community (vegetation units 4~6) showed negative correlation tendency with them.