• Journal of The Geomorphological Association of Korea
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• 제24권4호
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• pp.1-12
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• 2017

This study tried to reconstruct paleovegetation environments during the late Holocene with pollen analysis from archeological trenches at the right bank of Geumgang in Sejong-si. The lower hills was dominantly covered with pine trees, while alder trees and hygrophytes extended on the floodplain since 2,000yr BP. The pollen composition of Alnus dominance in the floodplain during the times is different from the general charateristics of Korean peninsula. Such a phenomenon is thought to be influenced by the fluvial process on the floodplain in the middle reaches of Geumgang around Sejong-si. Mihocheon and some tributaries join to Geumgang around Sejong-si, and the channel of Geumgang becomes narrow around the boundary between Sejong-si and Gongju-si. This narrow channel could attribute to the formation of extensive floodplain around Sejong-si. Moreover, human impacts such as agriculture appear continuously since 1,800yr BP.

• The Korean Journal of Mycology
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• 제25권2호통권81호
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• pp.152-160
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• 1997

In order to compare collected strains of Naematoloma sublateritium, electrophoretic isozyme and RAPD band patterns of DNA from mycelia were studied. The two characteristics of the strain, ASI 11010 were much different from those of ASI 11005 and 11006. These patterns may be used as valuable criteria for identifying strains of N. sublateritium. Optimal conditions on the vegetative growth of N. sublateritium using sawdust media were favourable on alder sawdust media added with 30% beer waste. Optimal water content was 70%.

• Journal of Ecology and Environment
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• 제34권4호
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• pp.371-379
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• 2011

To determine the peak dispersal times of allergenic pollen grains in Ulsan, Korea, we performed continuous airborne pollen counts at three stations (Sts. A, B, and C) in Ulsan from August 2009 to November 2010. Pollen grains were sampled using a Durham sampler. Two peak pollen dispersal seasons were observed per year. The peak seasons generally coincided with the flowering period of anemophilous trees: Taxodiaceae (February), Alnus (March), Cupressaceae (April), Quercus, and Pinus (May), and with the flowering phase of herbs from August to November, e.g., Humulus, Artemisia, Gramineae, and Ambrosia from August through September. The highest concentration of airborne pollen was from Pinus (68%), followed by Quercus (15%), Alnus (6%), and Humulus (2%); whereas very low pollen concentrations were from Taxodiaceae, Cupressaceae, Artemisia, Gramineae, and Ambrosia (${\leq}$ 1% of the annual total airborne pollen concentration). Our findings indicate that Alnus and Humulus pollen are major allergens whereas those of Pinus and Quercus are minor allergens. The concentration of Alnus pollen grains at St. C was over five times that at Sts. A and B. This finding implies that individuals living at or near St. C are exposed to high concentrations of Alnus pollen before and after March, which is the flowering period of the alder tree. From August to September, individuals living at or near St. B are exposed to high concentrations of Humulus pollen. Our study suggests that Alnus pollen may be the major aeroallergen causing pollinosis in the spring at St. C and Humulus pollen may be the major aeroallergen in autumn at St. B.

• Journal of the Korean Wood Science and Technology
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• 제29권4호
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• pp.25-32
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• 2001

A microwave vacuum (MW/V) dryer was developed for drying short roundwoods, from which woodcraft souvenirs in Korean market are mostly made, and which were hardly dried without defects in a conventional kiln. It consisted of three 1.5 kW magnetrons of 2,450 MHz, a vacuum pump, a load cell of 100 kg and a cavity of $580{\times}580{\times}1,360\;mm^3$. A computer program was developed to switch on or off the magnetrons according to drying schedules, those were based on microwave injection time or the average of wood temperatures. To evaluate the new MW/V dryer the roundwood specimens of rigida pine, poplar and birch were dried. Their log diameters and lengths ranged from 125 to 25 em and from 25 to 50 cm, respectively. In spite of the presence of minor drying defects, the MW/V drying is found to be an effective method for drying short roundwoods. Wooden turneries made of red alder and ash logs were also MW/V dried from green to 4%MC without any degradation. The rates of the MW/V drying were examined for three different lengths of poplar logs.

• The Korean Journal of Ecology
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• 제19권3호
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• pp.251-260
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• 1996

The effect of forest fire on soil microarthropod fauna was investigated in the Inhoo Park, located at Deokjin-gu, Chonju city, where fire burned about 2 hectares on April 5, 1994. Vegetation of the area was covered with mixed forest such as 20 to 30 year old black locust, alder, and pine gree, etc., and also rich in understory plants, dead leaves, twigs, etc. The soil samples were taken from burnt soil and near-by control site on April 10, June 6 and Oct. 22 in 1994, and June 26, 1995. Soil microarthropods were extracted using Tullgren apparatus for 72 hours. Soil microarthropods collected in this experiment were 8, 013 at control and 3, 805 at the burnt site making a total of 11, 818 from 5 classes. Therefore, appearance of microarthropods was reduced to 52.5% at burnt site. Dominant animal groups were Acari (45%) and collembola (46%). The reduced rate of soil animal density by fire damage was 52.5% of the total soil microarthropods accounting 36% in Acari and 70% in collembola. The reduction of soil animal density by fire was 65.3% by habitat destruction and 51.7% by diret shock from fire heat. In Collembola, 89% was reduced by habitat destruction. Oribatid mites collected at sample plots included 29 families, 47 genera and 58 species. Forty-two species at burnt site and 47 species at unburnt site were identified, of these 32 being common species at both sites. The density ratio of soil animals at the burnt sites and those at unburnt sites was 38.6% va 61.4% resulting in 37% reduction due to fire. The dominant species with more than 5% in relative density were Trichogalumna nipponica (7.3%) and Eremobelba japonica (5.8%) at unburnt site, shereas 5 species including Eohypochthonius crassisetiger (8.5%) at the burnt site. The number of these species were 32.1% of total number. MGP analysis based on the number of oribatid mites indicated GP type at both unburnt and burnt sites, revealing domination of the P group in oribatid mites.

• The Journal of Natural Sciences
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• 제7권
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• pp.47-51
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• 1995

In order to develope new asymmetric catalyst, we synthesized the following new sulfonamide derivatives start from S-Indoline-2-Carboxylic Acid via the following 5 steps. Hydroxy methyl derivative(1) was thus treated with methane sulfonyl chloride in the presence of triethylamine as base to give mesylated derivative(2) in 85% of isolated yield. The mesylate compound (2) was treated with excess sodium azide to give Azido derivative (4) in 95% isolated yield. Azido compound (3) was then reduced to the corresponding amino derivative in near quntitative yield by the hydrogenation under hydrogen atmospere in the presence of catalytic amount of Pd-C. The amino derivative (4) was converted to its sulfonamide derivatives by the treatment of compound(4) with triisopropyl benzene sulfonyl chloride in the presence of triethyl amine as base. Finally t-BOC group of the compound(5) was removed by the treatement of excess Trifluoro-acetic acid in near quantitative yield to give the target sulfonamide derivative (7) .in this paper we prepared compound(6) in 49% overall yield via the 5 steps of synthesis starting from t-Boc- 2-hydroxy methyl indoline(1) which cab be easily prepared from commercial available S-indoline-2-carboxylic acid by known methods. we plan to apply this new catalyst for the asymmetric reduction , diels-alder reaction, aldolcondensation reaction in due courses.

• Biomaterials Research
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• 제22권4호
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• pp.235-248
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• 2018

Background: Injectable hydrogels have been extensively researched for the use as scaffolds or as carriers of therapeutic agents such as drugs, cells, proteins, and bioactive molecules in the treatment of diseases and cancers and the repair and regeneration of tissues. It is because they have the injectability with minimal invasiveness and usability for irregularly shaped sites, in addition to typical advantages of conventional hydrogels such as biocompatibility, permeability to oxygen and nutrient, properties similar to the characteristics of the native extracellular matrix, and porous structure allowing therapeutic agents to be loaded. Main body: In this article, recent studies of injectable hydrogel systems applicable for therapeutic agent delivery, disease/cancer therapy, and tissue engineering have reviewed in terms of the various factors physically and chemically contributing to sol-gel transition via which gels have been formed. The various factors are as follows: several different non-covalent interactions resulting in physical crosslinking (the electrostatic interactions (e.g., the ionic and hydrogen bonds), hydrophobic interactions, ${\pi}$-interactions, and van der Waals forces), in-situ chemical reactions inducing chemical crosslinking (the Diels Alder click reactions, Michael reactions, Schiff base reactions, or enzyme-or photo-mediated reactions), and external stimuli (temperatures, pHs, lights, electric/magnetic fields, ultrasounds, or biomolecular species (e.g., enzyme)). Finally, their applications with accompanying therapeutic agents and notable properties used were reviewed as well. Conclusion: Injectable hydrogels, of which network morphology and properties could be tuned, have shown to control the load and release of therapeutic agents, consequently producing significant therapeutic efficacy. Accordingly, they are believed to be successful and promising biomaterials as scaffolds and carriers of therapeutic agents for disease and cancer therapy and tissue engineering.

• Journal of Sasang Constitutional Medicine
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• 제34권4호
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• pp.13-26
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• 2022

Objectives The purpose of this study was to explore the differences in allergic reactions by type of Sasang constitution using multiple allergen simultaneous test(MAST). Methods This study was conducted using the big data of Korean medical health checkups. Subjects with a history of allergic disease, Sasang constitution type information, and MAST results were included. Subjects who had taken drugs before MAST that affected allergic reactions were excluded. We compared total immunoglobulin E(IgE) concentrations, and the number of positive antigens by Sasang constitution using analysis of variance. The presence or absence of a positive reaction and specific IgE concentration classes of 92 antigens in MAST were analyzed by Fisher's exact test or Chi-squared test. Results The distribution of Sasang constitutional types of Tae-Yang, Tae-Eum, So-Yang, and So-Eum among 147 subjects was 2.7%, 42.9%, 38.1%, and 16.3%, respectively. There was no statistically significant difference in the total IgE concentration, the number of positive antigens, and specific IgE concentration classes for each antigen. There was a statistically significant difference in MAST-positive reaction for alder and pine antigens by type of Sasang constitution, and Tae-Eum had the most. Conclusions Tae-Eum showed a relatively strong positive reaction to a large number of antigens compared to the other types, but no statistically significant difference was observed. It is necessary to continuously investigate allergic reactions to provide evidence for the treatment of allergic diseases by Sasang constitution.

• Nuclear Medicine and Molecular Imaging
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• 제43권5호
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• pp.478-486
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• 2009

Purpose: 5-iododeoxyuridine analogues have been exclusively developed for the potential antiviral and antitumor therapeutic agents. In this study, we synthesized carbocyclic radioiododeoxyuridineanalogue (ddIVDU) and carbocyclic intermediate as efficient carbocyclic radiopharmaceuticals. Materials and Methods: The synthesis is LAH reduction, hetero Diels-Alder reaction as key reactions including Pd(0)-catalyzed coupling reaction together with organotin. MCA-RH7777 (MCA) and MCA-tk (HSV1-tk positive) cells were treated with various concentration of carbocyclic ddIVDU, and GCV. Cytotoxicity was measured by the MTS methods. For in vitro uptake study, MCA and MCA-tk cells were incubated with 1uCi of [$^{125}I$]carbocyclic ddIVDU. Accumulated radioactivity was measured after various incubation times. Results: The synthesis of ddIVDU and precursor for radioiodination were achieved from cyclopentadiene in good overall yield, respectively. The radioiododemetallation for radiolabeling gave more than 80% yield with > 95% radiochemical purity. GCV was more toxic than carbocyclic ddIVDU in MCA-tk cells. Accumulation of [$^{125}I$]carbocyclic ddIVDU was higher in MCA-tk cells than MCA cells. Conclusion: Biological data reveal that ddIVDU is stable in vitro, less toxic than ganciclovir (GCV), and selective in HSV1-tk expressed cells. Thus, this new carbocyclic nucleoside, referred to in this paper as carbocyclic 2',3'-didehydro-2',3'-dideoxy-5- iodovinyluridine (carbocyclic ddIVDU), is a potential imaging probe for HSV1-tk.

• Korean Journal of Agricultural and Forest Meteorology
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• 제12권1호
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• pp.23-35
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• 2010

For the sustainable conservation of forests within and around the somma of Nari basin in Ulleung Island, the stand structure and dynamics with the aspect, altitude and stand types were estimated by using analyses of importance value, plant species diversity, S$\o$rensen's similarity index and distributions of diameter classes. Results of the importance value analysis with vegetation stories on each stand showed that Fagus engleriana and Acer okamotoanum were dominant in most stands regardless of the aspect and altitude of the forest around the somma of Nari basin and the plant species composition among stands was not significantly different. The forest within Nari basin was composed of pine, beech, alder and deciduous-mixed stand. Moreover, the species composition was greatly different among the four stands. The diversity of plant species within stand was in general higher within Nari basin than around the somma, and among stands within Nari basin, the plant species diversity of pine and deciduous-mixed stand showed higher values than that of beech and alder stands. The similarity index among stands with aspect and altitude showed that the index among stands of eastern, western and northern slope in forest around the somma and forest within the basin ranged from 0.68 to 0.69, and the similarity among four stands with altitude was very high having index range from 0.85 to 0.95. The patterns of diameter class distribution of the major dominant species from four altitude classes followed an almost normal bell-shaped distribution. The results were interpreted as an indication that these forests will in general maintain a stable stand structure. Therefore, despite diverse topographic features around Nari basin, the stand structure and plant species composition among stands were not diversified as expected. For the conservation of diversity of forest plant species and of forest ecosystems, a promising and intensive program should be considered.