• Journal of the Korean Wood Science and Technology
• /
• v.32 no.1
• /
• pp.17-27
• /
• 2004

Cholesterol inhibitory activity was investigated to develop the functional food from edible forest resources such as Allium victorialis var. platyphyllum and other 12 species. Among tested samples by enzyme-linked immunosorbant assay (ELISA), leaf extracts of A. victorialis var. platyphyllum inhibited 73.9% of the activities of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) which is the highly regulated and major rate-limiting of the cholesterol biosynthesis pathway. Moreover, those extracts inhibited 76.7% of squalene synthase which catalyzes the head-to-head condensation of two farnesyl pyrophosphate molecules to form squalene in the biosynthesis of cholesterol. In order to find out the compounds which would play a key role in inhibitory activity of cholesterol, kaempferol and quercetin were isolated from the dichloromethane soluble fraction of extracts of A. victorialis var. platyphyllum. Kampferol, quercetin and each soluble fraction was also subjected to the test of the mRNA expression of HMG-CoA reductase and squalene synthase by reverse transcriptase-polymerase chain reaction (RT-PCR) assay, respectively. By treating both enzymes with 10 ㎍/㎖ of kaempferol and quercetin for 24 hours, respectively, the mRNA expression was not observed, suggesting that both compounds inhibited the biosynthesis of cholesterol at mRNA level. In this regard, it could be inferred that cholesterol inhibitory activity of A. victorialis var. platyphyllum was derived from kaempferol and quercetin. Both compounds have already been found in many plant extracts including hardwood and softwood, but it might be first known that they have cholesterol inhibitory activity.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.38
• /
• pp.265-302
• /
• 2008

This paper intends to analyse some legal issues on "Zeroing" which is based on the article 2.4.2 under the WTO Anti-dumping Agreement. "Zeroing" stands for a specific methodology in calculating a general dumping margin for a product in question under which negative individual dumping margins are treated as zero (thus "zeroed") before aggregating all individual dumping margins. The article 2.4.2 of the Anti-dumping Agreement regulates three types of calculating methodology on dumping margin as first symmetrical method(average-to-average: A-A), second symmetrical method(individual-to-individual: I-I) and asymmetrical method(average-to-individual: A-I). However, this article does not have any provisions about the "Zeroing" practice. In their anti-dumping practices, the EC and the United-States calculated dumping margin based on the "Zeroing", but this methodology has been disputed in the Dispute Settlement Body(DSB) of the WTO. This paper analysed their legal problems with some WTO cases in particular concerning EC-Bed Linen, U.S.-Softwood Lumber Zeroing, U.S.-Zeroing(EC) and U.S.-Sunset Review(Japan) cases. On the basis of theses analysis, we can therefore ask some questions as follows; To begin with, although the article 2.4.2 of the WTO Anti-dumping Agreement does not clearly refer to the "Zeroing", how do some developing countries, as the U.S.A and the E.U. calculate dumping margin as the "Zeroing"? Secondly, what is the relationship between the symmetrical method and asymmetrical method to the dumping margin? And if we adopt the zeroing method, what is the different rate to anti-dumping margin? Thirdly, although the Panel decided that the zeroing methodology of dumping margin used by th U.S.A in administrative review between the U.S.A and the E.U, why does the Appellate Body made the decision that the american methodology is incompatible with the WTO Anti-dumping Agreement? Lastly, what will be affected the upper decision taken by the Appellate Body to the DDA negotiation of anti-dumping matters? Even though the WTO Appellate made a decision that the zeroing method is incompatible with the principles of the WTO law, this methodology contains a lot of problems. Some members of the WTO as the U.S.A and the E.U did not officially declare this methodology to abandon, and the debate concerned is arguing. Therefore this paper tried to present the adequate solution in order to promote the zeroing methodology in the international anti-dumping system and practices.

• Journal of Forest and Environmental Science
• /
• v.14 no.1
• /
• pp.1-13
• /
• 1998

In this paper, it has been discussed on the relation between the anatomical features of woods and the penetration of methyl methacrylate monomer system into major Korean tree species, especially the Pinus koraiensis, Larix leptolepis, Quercus mongolica and Tilia amurensis. 1. There was some differences in penetration of polymers among different tree species, but generally the penetration of ring porous woods seems to be larger than that of diffuse porous woods and it was very difficult to penetrate to Larix leptolepis, especially to the that of heart wood. 2. The penetration on transeverse surface was relatively easy but radial and tangential impregnation were somewhat hard and differences between them were negligible. 3. The penetration of sapwood was larger than that of heartwood and its differences varied according to the existence of tyloses or contents in vessel. 4. Generally the polymer penetration of earlywood was larger than that of latewood in ring porous woods, but on the contrary, penetration of earlywood was small than that of latewood on diffuse porous woods. 5. Vessel diameter of wood had nearly no relation to polymers penetration. This seems to come from the reason that effective vessel diameter varies with the existence of tyloses or contents in vessel. 6. The penetration of ray tracheids was larger than that of ray parenchyma cells in softwoods, but penetration of hardwood rays seems to be small in comparison with softwood ray parenchyma cells. 7. Specific gravity and annual ring width had no relation to the penetration of polymer.

• Korean Journal of Plant Resources
• /
• v.33 no.4
• /
• pp.303-310
• /
• 2020

This study was conducted on propagation use for conservation scheme of a threatened plant; Wikstroemia ganpi (Sieb. et Zucc.) Maxim(Geomundo false ohelo). The seed propagation was showed higher (95%) in storage and lower values in ground and cutting. Softwood cutting was higher than hardwood cutting and it was possessing higher ratio of rooting that increase concentration of IBA and NAA. It was determined that for Geomundo false ohelo seedling was effective than cutting. In-situ and ex-situ conservation and restoration of substitute habitats of Geomundo false ohelo is therefore necessary due to human trampling in the habitats, damage, natural selection, loss and suppression.

• Journal of Bio-Environment Control
• /
• v.20 no.4
• /
• pp.346-351
• /
• 2011

This research was done to identify the mass propagation method in winter daphne (Daphne odora Thunb) using its softwood cuttings and to investigate its plant characters established at different light and soil conditions as an indoor plant. Cuttings from winter daphne were taken and grown in different treatment consisted of rooting media (perlite, vermiculite, perlite + vermiculite (1 : 1) and commercial horticulture media soil), indole butyric acid (IBA) hormone concentrations (0, 100, 500, 1000 ppm and Rootone) and date of cutting. Transplants were grown at different light intensities (100, 1000, 2500 lux and control) and growing media. Results showed that cuttings grown in perlite + vermiculite (1 : 1) gave higher percentage (100%) rooting. Cuttings treated with Rootone and IBA 100 ppm showed good rooting growth and cutting taken in June, 25 gave the highest rooting (96.7%). The best plant growth obtained at 1000 lux (56~60 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) followed by 2500 lux (125~130 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and scoria mixed with commercial horticulture media soil showed better growth of transplants.

• Journal of Plant Biotechnology
• /
• v.50
• /
• pp.200-206
• /
• 2023

Although softwoods are widely distributed in Korea and used in various industries, studies are limited and comparative research on softwoods has been overlooked. Therefore, in this study, the physiological activity of four species of softwoods found in Korea was quantified. Needles and cones of Pinus densiflora, Chamaecyparis obtusa, Cryptomeria japonica, and Abies koreana were collected, and material was extracted using 70% methanol. We quantified the following physiological traits: total phenol and flavonoid content, antioxidant activity (DPPH, TEAC, FRAP), and inhibitory activity of the enzymes α-glucosidase, elastase, and tyrosinase. Total phenol and flavonoid contents and antioxidant activities were high in Chamaecyparis obtusa and Cryptomeria japonica, and α-glucosidase inhibition activity was highest in the leaves of Chamaecyparis obtusa. Elastase inhibitory activity was high in the leaves and cones of Pinus densiflora and the cones of Abies koreana, and tyrosinase inhibitory activity was highest in the leaves of Pinus densiflora. In Korea, softwoods are planted extensively on roadsides and as windbreaks, and they are highly competitive in supplying raw materials since they are pruned every year. Based on the results of this study, softwoods are considered suitable for use in healthcare products, diabetes products, wrinkles, and whitening cosmetics.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.29 no.2
• /
• pp.130-138
• /
• 2011

This study was carried out to investigate growth characteristics and propagation methods of Clerodendron trichotomum for landscape uses. The results are obtained as follows: In the first place, Korean native C. trichotomum was printed in the "Enumeration of plants in Chosun" in 1937 by Tae Hyun Chung. C. trichotomum is a shrub with round shape. This is noted for its late summer flowers, showy fruit and malodorous foliage. White flowers in long-peduncled cymes bloom in the upper leaf axils from late summer into fall. Flowers are followed by small bright blue fruits, each subtended by a fleshy red calyx. C. trichotomum showed high seed germination rate and greater shoot length in plug box than in normal seeding bed. The rooting rate of C. trichotomum according to cutting date was highest on July 7. The optimum date for cutting was on July 7~10 when the shoots were more hardened. Soil acidity ranged from pH 4.58 to 5.52. The most effective method for rooting of C. trichotomum was treatment with 1,000 ppm IBA on July 7 cuttings, which showed rooting rate of over 90%. Korean native C. trichotomum was successfully propagated through soft cutting and seed.

• Journal of the Korean Wood Science and Technology
• /
• v.49 no.4
• /
• pp.336-359
• /
• 2021

In this study, hybrid CLT research and development trends were analyzed to improve the low rolling shear strength of CLT, a large wooden panel used in high-rise wooden buildings. Through this, basic data that can be used in research and development directions for localization of CLT were prepared. As a way to improve the low rolling shear strength, the use of hardwood lamina, the change of the lamina arrangement angle, and the use of structural composite materials are mainly used. Rolling shear strength and shear modulus of hardwood lamina are more than twice as high as softwood lamina. It confirmed that hardwoods can be used and unused species can be used. Rolling shear strength 1.5 times, shear modulus 8.3 times, bending stiffness 4.1 times improved according to the change of the layer arrangement angle, and the CLT strength was confirmed by reducing the layer arrangement angle. Structural wood-based materials have been improved by up to 1.35 times MOR, 1.5 times MOE, and 1.59 times rolling shear strength when used as laminas. Block shear strength between the layer materials was also secured by 7.0 N/mm², which is the standard for block shear strength. Through the results of previous studies, it was confirmed that the strength performance was improved when a structural wood based materials having a flexural performance of MOE 7.0 GPa and MOR 40.0 MPa or more was used. This was determined based on the strength of layered materials in structural wood-based materials. The optimal method for improving rolling shear strength is judged to be the most advantageous application of structural wood based materials with strength values according to existing specifications. However, additional research is needed on the orientation of CLT lamina arrangement according to the fiber arrangement of structural wood-based materials, and the block shear strength between lamina materials.

• Journal of Korean Society of Forest Science
• /
• v.85 no.3
• /
• pp.396-408
• /
• 1996

The purposes of this study were to standardise the forest working system to design the intensity of working system in felling operation of the thinning forest in our country as well as to contrive the improvement of working method and the increase of productivity. For the purpose of investigating these, element working was classified by felling operation in softwood thinning forest, and a pulse rate were measured and analyzed. The results were as follow : 1. From the analysis of the pulse frequence measurment, the average pulse showed 108 pulse per minute for worker A in the total of pure working time, 130 pulse per minutes for worker B, 119 pulse per minute for worker C and 125 pulse per minute for worker D, respectively. 2. From the results of the pulse frequence analysis according to element working classification, the highest pulse frequence represented 115 pulse per minute for worker A in the circumference, 131 pulse per minute for worker B in the movement, 122 pulse per minute for worker C in the limbing operation and 128 pulse per minute for work D in hang-up. 3. If the original pulse frequence was 100% for workers, the working intensity showed as follow : worker A was 160%(original pulse frequence was 61=100%) for the total of the working intensity and 188% for the circumference among element working. Worker B was 220%(original pulse frequence was 57=100%) for the total of the working intensity and 229 for movement among element working. Worker C was 159%(original pulse frequence was 73=100%) for the total of the working intensity and 168% for limbing operation among the element working. Worker D was 156%(original pulse frequence was 70=100%) for the total of working intensity and 182% for hang-up among element working. 4. At the limit point of Labor performance rating, showing the total of working intensity, overtime pulse rate per minute was 30 for worker A, 207 for worker B, 14 for worker C and 67 for worker D. Worker B was highest in working intensity, and got physically a big load.

• Journal of the Korean Wood Science and Technology
• /
• v.36 no.6
• /
• pp.147-158
• /
• 2008

In this study, fermentation characteristics of waste agricultural and forest biomass for production of heat energy were focused to be used in agricultural farm households. The purpose of this study was focused on seeking practical utilization of agricultural and forest biomass wastes in agricultural farm households in the form of thermal energy by means of simple fermentation process. Fermentation process was performed in terms of different raw-materials and their mixture with different ratios. Urea, lime, and bioaids were added as fermenting aids. Moisture contents of fermenting substrates were adjusted to 55~65%. In order to optimize the fermentation process various factors, such as raw-materials, moisture contents, amount of fermenting aids, and practical measurement of hot-water temperature during fermentation were carefully investigated. The optimum condition of fermenting process were obtained from hardwood only and hardwood: softwood (50 : 50) beds. In case of hardwood only the highest temperature was recorded between 60 to $90^{\circ}C$ the lowest temperature was determined to more or less $40^{\circ}C$ and the average temperature was ranged to $50{\sim}60^{\circ}C$ and this temperature ranges were maintained up to 20~30 days. The optimum amount of additives were estimated to ca. 15 kg of urea, 20 kg of bioaids, and 10 kg of lime for 1 ton of substrate. To reach the highest temperature the optimum moisture content of fermenting substrate was proved to 55% among three moisture content treatments of 45%, 55% and 65%. The temperature of hot-water tank installed in fermenting bed of hardwood : grass (50 : 50) showed very different patterns according to measuring positions. In general, temperatures in the mid- and upper-parts of substrate piling were relative higher than lower and surface parts during 45-day fermentation process. The maximum temperature of fermenting stage was determined to $65^{\circ}C$, minimum temperature, more or less $40^{\circ}C$, and average temperature was $60^{\circ}C$. The water temperature of tank exit was ranged to $33{\sim}48^{\circ}C$ during whole measuring periods. It could be concluded that fermentation process of waste agricultural and forest biomass produces a considerable amounts of heat, averaging about $50{\sim}60^{\circ}C$ for maximum 3 months by using the heat exchanger (HX-helical type).