• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.334-341
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• 2006

This study was to investigate the growth of planted red pine (Pinus densiflora S. et. Z.) seedling, soil properties and understory vegetation structure after fertilizer treatments [unfertilized plot (control), CF plot (Combination Fertilizer), UF plot (Urea Formaldehyde Fertilizer)] in a Pinus densiflora stand planted after the forest fires in Gosung, Gangwon province. The height growth rates of seedlings in four years were 264% in unfertilized, 404% in CF, and 388% in UF plots, respectively. The root collar diameters were increased 340% in unfertilized, 454% in CF, and 427% in UF plots, respectively. No significant changes occurred in soil total nitrogen and potassium ion ($K^+$) with the fertilization. However, available $P_2O_5$, content in the soil surface (0-15 cm) increased with the fertilizer application. Soil organic matter increased significantly with fertilizer treatments, while gradual decrease occurred in unfertilized plots. Sodium ion ($Na^-$) decreased in all sites. Soil pH, CEC, calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) contents were not significantly different among treatments. Although Shannon's species diversity index and species richness in understory vegetation did not change with fertilizer treatments, vegetation cover rates in forest floor increased significantly with the fertilization. These results suggest that the increase of pine seedling growth and vegetation cover rates with fertilization could enhance soil stabilization in forest tire areas.

• Journal of Korean Society of Forest Science
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• v.40 no.1
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• pp.1-18
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• 1978

Three Pinus densiflora populations as shown in location map (Fig. 1) were studied in 1977. These succeed the population numbers 10, 11 and 12 after the preceeding populations. Following the previous study methods, 20 trees were chosen from each population and the morphological characteristics such as tree forms, branching habit, needle and wood properties were investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 40 to 45. The growth performances of trees of population 10 and 11 was similar, but 12 seemed to be inferior more or less. 2. The ratios of clear bole length was 0.53 in population 12 as the highest but 0.43 for population 10 as the lowest. 3. The population 12 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown length) 1.65 though the mean branching angle indicates almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between populations as shown in Fig. 3 and 4. 5. No inter-population differences in serration density of needle was shown but significant inter and intra-population and individual differences (within population) in number of stomata rows and resin duct. 6. Population 12 shown 0.119 of resin duct index as the maximum. 7. The pattern of diameter growth, analyses based on the width of 10-year-ring segment unit (for example, the 1st segment denotes the width between pith center and 10th year ring and the 2nd one is from 11th to 20th year ring and so on.), was alike among populations as shown in Fig. 9. 8. No significant differences between population in mean summer wood percentages as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 10 and 11 however vice versa in population 12. 9. The fiber length was increased with the increase of age but no differences between populations as shown in Fig. 12.

• Journal of Science Education
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• v.32 no.1
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• pp.33-46
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• 2008

The purpose of this study was to know whether or not any wrongful description or simple errors were in photosynthesis unit of Biology II textbook under 7th national curriculum and if so, to know whether or not high school teachers recognized and corrected properly the mistakes. The mistakes in photosynthesis unit of text books were determined by the comparison with several reference books and through examination by three plant physiologists in 8 different Biology II textbooks. After the mistakes were analysed, the survey using contents of textbook containing the mistakes was conducted on high school teachers teaching Biology II. As a result, 48 mistakes were determined in 13 subjects. As many as four mistakes were found even in one subject in a certain textbook and a same mistake was found repeatedly in several textbooks. The survey result showed that the teachers who pointed exactly the mistakes out corrected properly, however, the percentage of these ones out of 35 teachers replied to survey was less than 50%. The ratios of correction out of total number of responses were high in question #6 (43%), #4-3 (40%), and #1-2 (32%) which were containing a simple mistake in graph, a wrong word and a wrong picture, respectively. But, no one pointed out and made correction in question #5-1 and #5-2 which were containing Z scheme of light reaction without the legend of vertical axis that should be explained as electron energy or standard reduction potential. The result indicates the possibility that the mistakes in photosynthesis unit of Biology II textbook can be corrected and teached properly by teachers may be low. In order to reduce the possibility that students may have misconceptions about photosynthesis, the list of print's errors should be provided to the teachers and/or the training program and/or workshop for in-service high school biology teachers was recommended.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.183-190
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• 2009

Characterization of the analysis of forest vegetation, soil environmental conditions and water quality were performed from March 2003 to March 2007. The two basins were characterized by cultivated area (Kaesim reservoir) and mountain area (Jangchan reservoir), and divided into eleven small basins, where dynamics of pollutants, forest vegetation and soil environmental conditions were surveyed. The vegetation can be divided into 10 types by $Z\ddot{u}rich$-Montpellier school's method. Pearson coefficients between vegetation type and water quality were correlated with dissolved oxygen (DO) in the Quercus variabilis community at the 5% level and total phosphorus (TP) in the Larix leptolepis plantation at the 1% level. Especially total phosphorous and total nitrogen increased in small basins where the proportion of cultivated and residential area increased. The analysis of influences of pollutant discharge on water quality showed that pollutant charge was very low in forest land area ($Y_{T-P}$=-0.0017X+0.2215, r=0.16, $Y_{COD}$=- 0.0395X+8.5051 r=0.47). The soil types of western area were comparatively simple, but those of eastern area were complicated with regosols, red-yellow soils, lithosoles, etc. The pH, total solid (TS) and volatile substance (VS) of the forest and agricultural land soils collected in each site were 5.4~6.9, 75.8~80.2%, and 3.80%~5.80%, respectively. According to the analytical result of soil environmental conditions, heavy metal contents fell short to the mean value of natural conditions. Runoff amount (Y) and depth of topsoil (X) were negatively correlated, $Y_{ron}=-1.0088X_{top}+35.378$ (r=0.68). The correlation was much lower in up-stream but much higher in down-stream, because permeation into soil particle was larger on down-stream due to its more or less gentle slope. Pearson coefficients between soil pH and water pH were statistically significant at 1% level.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2005.12a
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• pp.38-45
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• 2005

The egg bags of Korean salamander(Hynobius leechii) were collected from farmlands in Gyeongsangnam-do area. The assumed breeding time, numerical variation of embryos in each egg bag, mortality and the rates of abnormalities were investigated. The toxicity of benomyl, the metabolite carbendazim and BIC which were frequently spread in agricultural area and caused spontaneous embryonic malformation was investigated. The assumed breeding time between the end of February and the end of March has the difference about a month because of a habitat and it takes about 2 or 3 weeks from laying eggs to hatching. The length of each egg bag and the number of embryos were very varied in each area. It is due to geographical variation. Among egg bags in total study area, only 406 of egg bags(17.70% of total egg bags) developed all of embryos to normal larvae, and 78.49% of total embryos were normally developed. The patterns of spontaneous embryonic malformation were 26 species from A to Z and the abnormal patterns in individual were 8 species and above. the geographical differences about the abnormal pattern were identified and 11 habitats categorized 4 groups. The most frequent abnormality in Gyeongsangnam-do area is the dysplasia of external gill. The caudal dysplasia, abdominal blister and dysplasia of fin were also frequently observed. Individuals showing severe external defect were histologically studied and they showed retinal hypo-pigmentation, thyroid carcinoma, somatic muscular dysplasia, degeneration of cephalic neuron and various organ dysplasia. Benomyl and carbendazim were treated by 10pM$^{\sim}$10uM and BIC was treated by 1$^{\sim}$40ppm to know the effect of toxicity about toxic substance of salamander. After benomyl was treated, a survival rate was sharply dropped from 2 to 8 days. $LC_{100}$ identified in $1{\mu}M$, $LC_{50}$ identified between 100nM and $1{\mu}M$. $EC_{50}$ was assumed between 10nM and 100nM. The prevalent external malformation was abdomen swelled abnormally and histo-pathological effects were abdomen, neural tube and lens hernia. This suggests that benomyl is the toxicitic substance which inhibits the development of digestive system and nervous system. The result of treated carbendazim was similar to that of the treated benomyl. The survival rate is sharply dropped between 2 and 6 days. $LC_{100}$ was identified $1{\mu}M$ and $LC_{50}$ was identified between 10nM and 100nM. This shows that cabendazim has stronger lethal toxicity than benomyl. Ventral blister, eye dysplasia and cephalic dysplasia in the individual of external malformation mean that cabendazim affected nervous system much more than benomyl. Because the toxicity of BIC affected less in the beginning but affected more in the near hatching period, the period causing toxicity is somewhat different. $LC_{100}$ identified near 40ppm and $LC_{50}$ identified near 25ppm. The external defect shows mainly ventral blister and histo-pathological results show intestinal deformities. This result suggests the BIC inhibited strongly the development of digestive system. These abnormal developments may be caused by antimitotic action, inhibition of tubulin complex, destruction of microtubule, inhibitions of neurulation and closing of neural fold, and by the inhibition of movement of neural crest cells of benomyl. These abnormal developments may be caused by the rupture of epithelium, the loss of microtubule, the reduction of spindle size, the inhibition of spindle assembly formation, the destruction of spindle poles of carbendazim. These abnormal developments may be caused cytotoxicity by inhibition of the synthesis of a number of macromolecules and similar reaction the inhibition of benomyl.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.117-129
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• 2010

The vascular plants of the 15 sites of Taeanhaean National Park were identified as 493 taxa; 117 families, 326 genera, 436 species, 49 varieties, 6 form, 2 hybrids. The National Park area includes coastal areas and islands, these islands reflects well the floristic characteristics of coastal area and transition area of the middle province and the southern province. The study revealed that Ficus erecta Thunb., Machilus thunbergii S. et Z., Neolitsea sericea (Bl.) Koidz. and Eurya japonica Thunb. etc. were the mainly distributed species in the southern area while Rosa rugosa Thunb., Carex kobomugi Ohwi and Elymus mollis Trin., etc. were mainly distributed species over the coastal dune area. Deciduous and evergreens broad-leaved trees like Acer palmatum Thunb. ex. Murray, Euonymus japonica Thunb. and Camellia japonica L., etc. were all together distributed in Taeanhaean National Park. There are no any Endangered species designated by The Ministry of Environment were not found. The floristic special plants were recorded to a total of 53 taxa; that is, class I species (41 taxa) were containing as Vitex rotundifolia L. Fil., Arisaema heterophyllum Bl. and Arisaema ringins (Thunb.) Schott, etc, class II species (1 taxon) were Iris ensata var. spontanea (Makino) Nakai, class III species (7 taxa) were containing; Koelreuteria paniculata Laxm., Salsola collina Pall. and Daphniphyllum macropodum Miq., etc, class IV species (1 taxon) were Angelica japonica A. Gray, class V species (1 taxon) were Utricularia vulgaris var. japonica (Makino) Tamura. The naturalized plants were identified a total of 52 taxa; 17 families, 44 genera, 51 species, 1 form; Solanum carolinense L., Phytolacca americana L. and Oenothera odorata Jacq., etc. Among them the ecosystem disturbance wild animals·plants was identified as Solanum carolinense L. Hypochoeris radicata L. and Solidago altissima L. The study suggests that these areas require management such as physical remove of this ecosystem disturbance field plants.

• Journal of Oral Medicine and Pain
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• v.30 no.2
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• pp.269-276
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• 2005

This in vitro study evaluated the influence of a flowable composite resin on the tensile bond strength of resin to enamel and dentin treated with Er:YAG laser and diamond bur. 96 Buccal enamel and mid-coronal dentin were laser-irradiated using an Er:YAG laser and treated with diamond bur. Each groups(48) were divided two small groups depends on acid-etching procedure. Light-cure flowable resin(Metafil Flo) and self-cure resin(Clearfil FII New Bond) were used in this study. After surface etching with 37% phosphoric acid and the application of an adhesive system, specimens were prepared with a hybrid composite resin. After 24hours storage in distilled water at 37$^{\circ}C$, all samples were submitted to the tensile bond strength evaluation, using a universal testing machine(Z020, Zwick, Germany). The obtained results were as follows: 1. TBS of acid-etching group were higher than those of non-etching group in both enamel and dentin treated with Er:YAG laser and diamond bur. Laser 'conditioning' was clearly less effective than acid-etching. Moreover, acid etching lased enamel and dentin significantly improved the microTBS of M-Flo. 2. In enamel, TBS of laser-irradiated group were lower than those of bur-prepared group. However, in flowable resin subgroup, there were not differed those between two groups in dentin. 3. In laser-treated group, TBS of flowable composite resin were higher than those of self-curing resin in dentin, however, there was no difference in enamel. From this study, we can conclude that the self- and light-cure composite resin bonded significantly less effective to lased than to bur-cut enamel and dentin, and that acid-etch procedure remains mandatory even after laser ablation. We suggest that Er:YAG laser was useful for preparing dentin cavity with flowable resin filling.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.3
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• pp.419-430
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• 2000

The purpose of this study was to compare the microleakage pattern of preventive resin restoration using conventional composite resin and flowable composite resin that recently developed. 60 sound premolar teeth were allocated to three groups. Flowable composite resin was used for the experimental groups(Group I and II) and conventional resin for the control group(Group III). After composite filling and sealant application, all teeth were thermocycled and evaluated for microleakage under light microscope. Additionally, a variety of voids formed inside restorations were also evaluated. Data were analyzed statistically using Kruskal-Wallis test and/or Mann-Whitney U-test. The results of the present study were as follows. 1. Microleakage found in all samples was only limited to the interface of restoration margin and enamel. 2. The flowable composite resin groups (Group I, II) generally showed less microleakage than control groups (conventional preventive resin restoration) (p<0.05) 3. Various types of voids were observed in most specimens. Especially, there was a tendency for more and larger voids to be found in group I, II than group III (p<0.05).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.375-395
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• 2006

Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1395-1401
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• 2012

This study investigated the cognition-related effects on antioxidant activities, ${\gamma}$-aminobutyric acid (GABA) contents, and AChE inhibitory activities in ethanol extracts from Zingiber officinale Rosc. (Korea), Curcuma longa L. (Korea), Curcuma longa L. (Myanmar), and Curcuma aromatica Salisb. (India). These extracts were investigated to determine the relationships among total polyphenols as well as DPPH and ABTS radical scavenging activities, GABA contents, and acetylcholinestrase (AChE) inhibitory activity. For the results, C. longa L. from Myanmar exhibited the highest contents of curcumin (97.1 ${\mu}g/mg$), total polyphenols (98.4 ${\mu}g/mg$), and GABA (1.31 ${\mu}g/mg$), as well as the strongest radical scavenging activities and AChE inhibitory activity. In addition, C. aromatica Salisb from India, which had the highest total polyphenol content (98.4 ${\mu}g/mg$) and strongest radical scavenging activities, exhibited relatively high AChE inhibitory activity similar to that of C. longa L. from Myanmar. On the other hand, Z. officinale Rosc. and C. longa L. from Korea showed low contents of curcumin (12.2 ${\mu}g/mg$) and polyphenols (85.7 ${\mu}g/mg$), as well as low AChE inhibitory activities. However, we could detect 1.11 ${\mu}g/mg$ of GABA in these extracts, which was similar to that of C. longa L. from Myanmar. Therefore, GABA content was not correlated with AChE inhibitory activity. Based on the results, AChE inhibitory activity is highly correlated with polyphenol contents in Zingibearceae family. Overall, among the Zingiberaceae tested, C. longa L. from Myanmar might be a strong candidate as a cognitive-enhancing ingredient.