• Title/Summary/Keyword: long term

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Studies on Cryo-preservation of Registered Strains of Lentinula edodes (표고 등록균주의 초저온 보존에 관한 연구)

  • Ryu, Sung-Ryul;Bak, Won-Chull;Koo, Chang-Duck;Ka, Kang-Hyeon
    • Journal of Korean Society of Forest Science
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    • v.98 no.1
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    • pp.115-124
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    • 2009
  • New strain needs to maintain desirable characteristics for long term when it was bred, but in lapse of time it degenerates into a bad condition. Therefore the influence of temperature on the viability and survival rates of Lentinula edodes strains were examined after cryopreservation. Also, liquid nitrogen preservation for L. edodes has been proved to be one of the most reliable method. However, a mechanical damage of strain is inevitable during cryopreservation of the fungus because the fungus is very sensitive to stress of cooling rate in the freezing process. So we tried to find out state change of L. edodes with a programmable freezer. L. edodes strains were preserved at $-20^{\circ}C$, $-80^{\circ}C$ and $-196^{\circ}C$ for 50 days. At $-20^{\circ}C$, its mycelial growth became extinct. When thawed, the growth of mycelia which were preserved at $-80^{\circ}C$ was fastest. Attempts were made to investigate viability of L. edodes strains after freezing at $-80^{\circ}C$ and $-196^{\circ}C$, respectively. As the result, more than 90% showed high survival rate of strains tested at $-80^{\circ}C$ and $-196^{\circ}C$. Mycelial growth between apical and basal parts of colony after freezing preservation for 50 days was compared. At apical and basal parts, the survival rates showed 100% at $-80^{\circ}C$, but 98% and 94% at $-196^{\circ}C$, respectively. We confirmed that the ice crystal formation temperatures of L. edodes strains were $-6.0^{\circ}C$ for Sanlim 1, $-5.5^{\circ}C$ for the Sanlim 2, $-4.0^{\circ}C$ for the Sanlim 3 and $-15.5^{\circ}C$ for the Sanzo 302. These results indicated that L. edodes strains showed completely different responses to the ice crystal formation. We knew the fact that even the same species, especially L. edodes, they displayed completely different responses to the same freezing condition. Also, this has nothing to do with the connection between temperature type and freezing point. And a protocol was tried to minimize state change of L. edodes strains using programmable freezer when they are frozen, but it was not effective on them.

Fine Root Biomass in Pinus densiflora Stands using Soil Core Sampling and Minirhizotrons (토양 코어 및 미니라이조트론을 이용한 소나무 임분의 세근 바이오매스 연구)

  • Han, Seung Hyun;Yoon, Tae Kyung;Han, Saerom;Yun, Soon Jin;Lee, Sun Jeoung;Kim, Seoungjun;Chang, Hanna;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.103 no.1
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    • pp.37-42
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    • 2014
  • Fine root distribution was investigated in Pinus densiflora stands using soil core sampling and minirhizotrons, and conversion factors and regression equations were developed for converting minirhizotron data into fine root biomass. Fine root biomass was measured by soil core sampling from October, 2012 to September, 2013 once a month except for the winter, and surface area of fine roots was estimated by minirhizotrons from May to August, 2013 once a month. Fine root biomass and surface area were significantly higher in the upper soil layers than in the lower soil layers. Fine root biomass showed seasonal patterns; the mean fine root biomass ($kg{\cdot}ha^{-1}$) in summer (3,762.4) and spring (3,398.0) was significantly higher than that in autumn (2,551.6). Vertical and seasonal patterns of fine root biomass might be related to the soil bulk density, nutrient content and temperature with soil depth, and seasonal changes of soil and air temperature. Conversion factors (CF) between fine root surface area from minirhizotron data and fine root biomass from soil core sampling were developed for the three soil depths. Then a linear regression equation was developed between the predicted fine root biomass using CF and the measured fine root biomass (y = 79.7 + 0.93x, $R^2=0.81$). We expect to estimate the long-term dynamics of fine roots using CF and regression equation for P. densiflora forests in Korea.

Thinning Intensity Effects on Carbon Storage of Soil, Forest Floor and Coarse Woody Debris in Pinus densiflora Stands (간벌 강도가 소나무림의 토양, 낙엽층 및 고사목 탄소 저장량에 미치는 영향)

  • Ko, Suin;Yoon, Tae Kyung;Kim, Seongjun;Kim, Choonsig;Lee, Sang-Tae;Seo, Kyung Won;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.103 no.1
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    • pp.30-36
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    • 2014
  • This study examined the change in carbon (C) storage of soil, forest floor and coarse woody debris (CWD) for different thinning intensities in Pinus densiflora stands 4 years after the treatment. Two study stands were located in Jeongseon (Stand 1) and Gwangneung Experiment Forest (Stand 2). Three plots for different thinning intensities based on stand density were established at each stand in 2008; control plot (0%), T20 plot (20%) and T30 plot (30%) in Stand 1 and control plot (0%), T39 plot (39%) and T74 plot (74%) in Stand 2, respectively. The C storage of soil (0-50 cm), forest floor and CWD was measured in 2012. Total C storage of T30 plot ($109.80t{\cdot}C{\cdot}ha^{-1}$) was significantly higher than that of control plot ($86.69t{\cdot}C{\cdot}ha^{-1}$) in Stand 1. In stand 2, total C storage of T74 plot ($97.02t{\cdot}C{\cdot}ha^{-1}$) was significantly higher than that of control plot ($72.04t{\cdot}C{\cdot}ha^{-1}$) and T39 plot ($63.25t{\cdot}C{\cdot}ha^{-1}$). Total C storage of the heaviest thinned plot was the highest in each study stand. Since this study examined initial effects of thinning on C storage of soil, forest floor and CWD, further studies would be necessary to evaluate the long-term effects.

The Immunohistochemical Expression of Nuclear Retinoid Receptor and CREB in Gastric Adenocarcinoma (위선암종에서 핵의 Retinoic Acid Receptor (RAR) 및 cAMP Response Element Binding Protein (CREB)의 면역조직화학적 발현양상)

  • Han, Ho-Sun;Kim, Yong-Seok;Park, Joong-Min;Choi, Yoo-Shin;Cha, Seong-Jae;Kim, Mi-Kyung;Chi, Kyung-Choun
    • Journal of Gastric Cancer
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    • v.8 no.4
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    • pp.182-188
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    • 2008
  • Purpose: Transcriptional factors of CREB (cAMP response element binding protein) are involved in regulating the gene expression in response to a variety of signaling pathways. The proteins produced by the CREB genes play key roles in many physiological processes, including memory and long-term potentiation. The retinoic acid receptor (RAR) axis mediates epithelial cell differentiation and proliferation in many tissues. This study examined the expressions of RAR and CREB and their relationship with the clinicopathologic factors and their significance. Materials and Methods: The levels of the RAR and CREB expressions were measured in 150 gastric adenocarcinomas by performing immunohistochemical staining. Results: 1. An RAR protein expression was found in 63.3% of the adenocarcinomas (95/150) and a CREB expression was found in 60.7% (91/150) of the adenocarcinomas. 2. An RAR protein expression was found in 72.2% (78/108) of the intestinal type adenocarcinomas and in 40.5% (17/42) of the diffuse type adenocarcinomas (P<0.05). Based on the depth of invasion, an RAR protein expression was found in 58.3% (14/24) of the T1 adenocarcinomas, in 61.9% (13/21) of the T2 adenocarcinomas, in 63.5% (61/96) of the T3 adenocarcinomas, in 77.8% (7/9) of the T4 adenocarcinomas and in 74.7% (62/83) of the adenocarcinomas with lymph node metastasis and in 49.2% (33/67) of the adenocarcinomas without lymph node metastasis (P<0.01). 3. A CREB expression was found in 69.4% (75/108) of the intestinal type and in 38.1% (16/42) of the diffuse type (P>0.05). Based on the depth of invasion, a CREB expression was found in 50% (12/24) of the T1 adenocarcinomas, in 52.4% (11/21) of the T2 adenocarcinomas, in 64.6% (62/96) of the T3 adenocarcinomas, in 66.6% (6/9) of the T4 adenocarcinomas, in 71.1% (59/83) of the adenocarcinomas with lymph node metastasis and in 47.8% (32/67) of the adenocarcinomas without lymph node metastasis (P<0.01). 4. The RAR protein and CREB expressions coincided in 71.4% of the gastric adenocarcinomas and a significant correlation between them was found (P<0.05). Conclusion: We found a significant relationship between the expression of RAR and CREB and the histology and lymph node metastasis of gastric cancer. Further studies are needed to confirm their biologic meaning in gastric carcinogenesis.

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The Economic Effects of Tax Incentives for Housing Owners: An Overview and Policy Implications (주택소유자(住宅所有者)에 대한 조세감면(租稅減免)의 경제적(經濟的) 효과(效果) : 기존연구(旣存硏究)의 개관(槪觀) 및 정책시사점(政策示唆點))

  • Kim, Myong-sook
    • KDI Journal of Economic Policy
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    • v.12 no.2
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    • pp.135-149
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    • 1990
  • Housing owners in Korea have a variety of tax advantages such as income tax exemption for the imputed rent of owner-occupied housing, exemption from the capital gains tax and deduction of the estate tax for one-house households. These tax reliefs for housing owners not only conflict with the principle of horizontal and vertical equity, but also lead to resource misallocation by distorting the housing market, and thus bring about regressive distribution effects. Particularly in the case of Korea with its imperfect capital market, these measures exacerbate the inter-class inequality of housing ownership as well as inequalities in wealth, by causing the affluent to demand needlessly large housing, while the poor and young experience difficulties in purchasing residential properties. Therefore, the Korean tax system must be altered as follows in order to disadvantage owner-occupiers, especially those owners of luxury housing. These alterations will promote housing-ownership, tax burden equity, efficiency of resource allocation, as well as the desirable distribution of income. First, income tax deductions for the rent payments of tenants are recommended. Ideally, the way of recovering the fiscal equivalence between the owner-occupiers and tenants is to levy an income tax on the former's imputed rents, and if necessary to give them tax credits. This, however, would be very difficult from a practical viewpoint, because the general public may perceive the concept of "imputed rent" as cumbersome. Computing the imputed rent also entails administrative costs, rendering quite reasonable, the continued exemption of imputed rent from taxation with the simultaneous deduction in the income tax for tenants. This would further enhance the administrative efficiency of income tax collection by easing assessment of the landlord's income. Second, a capital gains tax should be levied on the one-house household, except with the postponement of payments in the case that the seller purchases higher priced property. Exemption of the capital gains tax for the one-house household favors those who have more expensive housing, providing an incentive to the rich to hold even larger residences, and to the constructors to build more luxurious housing to meet the demand. So it is not desirable to sustain the current one-house household exemption while merely supplementing it with fastidious measures. Rather, the rule must be abolished completely with the concurrent reform of the deduction system and lowering of the tax rate, measures which the author believes will help optimize the capital gains tax incidence. Finally, discontinuation of the housing exemption for the heir is suggested. Consequent increases in the tax burden of the middle class could be mitigated by a reduction in the rate. This applies to the following specific exemptions as well, namely, for farm lands, meadows, woods, business fields-to foster horizontal equity, while denying speculation on land that leads to a loss in allocative efficiency. Moreover, imperfections in the Korean capital market have disallowed the provision of long term credit for housing seekers. Remedying these problems is essential to the promotion of greater housing ownership by the low and middle income classes. It is also certain that a government subsidy be focused on the poorest of the poor who cannot afford even to think of owning a housing.

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Anti-hypertensive Activities of Lactobacillus Isolated from Kimchi (김치에서 분리한 유산균의 항고혈압 활성)

  • Yu, Mi-Hee;Im, Hyo-Gwon;Im, Nam-Kyung;Hwang, Eun-Young;Choi, Jun-Hyeok;Lee, Eun-Ju;Kim, Jong-Boo;Lee, In-Seon;Seo, Hwa-Jeong
    • Korean Journal of Food Science and Technology
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    • v.41 no.4
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    • pp.428-434
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    • 2009
  • This study was conducted to evaluate the anti-hypertensive effect of Lactobacillus sp. isolated from Kimchi by examining its effects on renal angiotensin-converting enzyme (ACE) inhibitory activity, lipid components and blood pressure using the spontaneously hypertensive rat (SHR) system. Most Lactobacillus sp. extracts (lysozyme, sonication and ethyl acetate extracts) showed higher capacities for the inhibition of ACE activity than those of cultured media. Particularly, LG 7, 8 and 42 of Lactobacillus sp. showed the strongest inhibitory activity among the Lactobacillus sp. extracts. The concentrations of total cholesterol and triglycerides in the serum were lower in the Lactobacillus sp. administration groups than in the control group, but these differences were not significant. The HDL-cholesterol concentrations of the LG 42 administration groups (IX, X) were significantly higher than that of the control group. At 4 weeks, the systolic blood pressure (SBP) in the LG 42 Lactobacillus sp. ($1{\times}10^9$ cfu/mL) group (XI) was about 27% lower than that of the control group (V). No adverse effects were observed on the liver and there was no difference in the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values among groups. The results of this study suggest that long term consumption of LG 42 Lactobacillus sp. may be beneficial to the prevention of high blood pressure.

Analysis and the Standardization Plan of the Terms Used by Seafarers on Small Vessel (소형선박 종사자 사용용어 실태 분석 및 표준화 방안)

  • Kang, Suk-Young;Ryu, Won;Bae, Chang-Won;Kim, Jong-Kwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.7
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    • pp.867-873
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    • 2019
  • As of August 2019, there were 3,823 vessels under 30 tons that could be included in the category of small vessels; these account for 42.5 % of the 9,001 registered vessels in Korea. The problem is that many small vessel seafarers face many problems such as an board communication disconnection, difficulties in communication in maritime license interviews, or education related to maritime training using a large number of nonstandard terms, which are derived from foreign languages; this is leading to a decline the job skills of small vessel seafarers. Therefore, in this study, we closely analyzed the terminology of small vessel seafarers and proposed a standardization plan. In the terminology analysis, the preliminary terms of the maritime license interview and the high-frequency terms of the small vessel educational textbook were identified and the corresponding nonstandard terms were examined. Based on a survey, an expert meeting was held and incorrect Japanese notation, English notation, and the standard language for key terms were presented to analyze which questionnaire was most familiar. The ratio of the use of standard words is relatively high in the case of nautical terms, however, the wrong Japanese notation is used more for engine terms; the analysis results by age and tonnage also generally use the Japanese notation and the use frequency of English notation was determined to be low. Based on this, short- and long-term plans for the use of standard words by small vessel seafarers were proposed, including the production of a standard language dictionary for terms used by these seafarers, a promotion of the importance of using standard terms, active education through educational institutions, and the systematic preparation and implementation of Korean-language education for foreign sailors.

Analysis of Overseas LNG Bunkering Business Model (해외 LNG벙커링 비즈니스 모델 분석)

  • Kim, Ki-Dong;Park, So-Jin;Choi, Kyoung-Sik;Cho, Byung-Hak;Oh, Yong-Sam;Cho, Sang-Hoon;Cha, Keunng-Jong;Cho, Won-Jun;Seong, Hong-Gun
    • Journal of the Korean Institute of Gas
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    • v.22 no.1
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    • pp.37-44
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    • 2018
  • As the international Maritime Organization is tightening up the emission regulation vessel, many countries and companies are pushing ahead the LNG fuel as one of long term solution for emission problems of ship. as a study on the way to conduct business for LNG bunkering around the world, this study was analyzed in view-point of business models focused on major countries such as Japan, China, Singapore, Europe and United States. The results of this study are as follows. China first established a nation-centered LNG bunkering policy. And then, the state and the energy company have been cooperating and carrying on LNG bunkering business for LNG fueled ships. Some countries in Europe and United States are in the process of LNG bunkering business mainly with private company. To obtain cheaper LNG fuel than bunker-C, the private company has a business model of LNG bunkering on their own LNG fueled ships, while securing LNG with high price competitiveness through partnership with middle class operators such us LNG terminal and natural gas liquefaction plant. Also, the LNG bunkering business around the world is focused on private companies rather than public corporations, but it was going to be focused on large energy companies because the initial cost required to build LNG bunkering infrastructure. Three models (TOTE model, Shell model, ENGIE model) of LNG bun kering business are currently being developed. It has been found that the way in which LNG bunkering business is implemented by different countries is applied differently according to the enterprise and national policy.

An Investigation of Local Naming Issue of Phoenix dactylifera (대추야자나무(Phoenix dactylifera)의 명칭문제 고찰)

  • Kim, Young-Sook
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.34-44
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    • 2018
  • In the Ancient Mesopotamia, Egypt, Judas, Greece, and Rome, Phoenix dactylifera was planted in gardens or orchards to signify life, blessing, and victory. Branches of Phoenix dactylifera, likened to high and precious, were referred to one of the gifts to the king in the second century BC and have been used in the Feast of Tabernacles. And they were engraved on the walls of the temple and along with cherub. Besides, Phoenix dactylifera is compared with a righteous person in the Bible since it grows straight despite strong winds. And, it was used as a symbol of honesty, justice, and right. Churches call the week before Easter Palm Sunday since the crowd laid the leaves of date palm trees on the road and shouted "Hosanna" while waving the date palm branches when Jesus entered Jerusalem. Moreover, pilgrim in the Middle Ages was called 'Palmer' in English due to custom of returning with the leaves and branches of date palm trees as a memorial of the Holy Land pilgrimage. This study analyzes naming issue of Phoenix dactylifera through the old literature and 27 versions of the most influential Bibles in History of Bible Translation in Korea, China, and Japan. Phoenix dactylifera is translated into Chinese as '棕櫚(Trachycarpus fortunei)', a native tree of China. 棕櫚 is similar to Phoenix dactylifera, but its fruit and leaf are quite distinct. This being so, translating Phoenix dactylifera as 棕櫚 has a limit to convey symbolic meaning adequately. In the Japanese Bible, on the other hand, Phoenix dactylifera is translated as 'なつめやし(Natsumeyashi)' meant date palm tree. Most of Protestant Bible in Korea use 'Jongryeo' like Chinese Bible while translation in Korean Catholic Bible(2005) varies from one scripture to another: 'Yaja Namu (Palm Tree)' - 38 times, 'Jongryeo Namu' - 5 times, and 'Daechu Yaja Namu (Date Palm Tree)' - 3 times. Date Palm Tree, 'Jongryeo Tree', and Palm Tree don't grow in Korea. However, they had long been recognized as Haejo(海棗), Jongryeo(?櫚), and Yaja(椰子) respectively through China and Japan. Each of them called by a distinct name correspond with its own characteristic and used separately in Korean Classics as Jongryeo and Haejo were identified in ancient Chinese literatures. It seems that more confusion was raised since 'Palm' was translated as 'Jongryeo' in several books including "?藤和英大辭典 (1915)", "Modern 朝鮮外來語辭典(1938)", and "Latin-Korean Dictionary(1995)". However, the Latin term 'Palmae' is translated into English as either palm tree or date palm. The results of this study suggest that more accurate translation of Phoenix dactylifera in the Bible would be 'Daechu Yaja Namu (Date Palm Tree)' and using different name fit for its own characteristic would be more appropriate.

The Life Cycle of Tour Destination Hot Spring in Korea (한국 온천관광목적지의 수명주기)

  • Cho, Sung-Ho;Lee, Kyung-Ja
    • Journal of the Korean association of regional geographers
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    • v.4 no.2
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    • pp.165-182
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    • 1998
  • When tour site is being used by people for the destination of tour, it has a life, or it will lose its life as a tour site. Therefore this paper aims to, based on Butler's theory, has chosen 46 hot spring spots in Korea which are legally assigned and presently running, and tried to analyze the life cycles, the stage of dispositional characteristics, and visitors' favoritism, and to try to find activating method which is not decline. Out of 46 spots, 29 Places were found on the stage of development, which took high percentage, 4 were on the growing stage, 5 were on the mature stage, 5 were on the stagnation or decline stage and the rest 3 were on the stage of rejuvenation. Geographically, Korean hot springs were located on the plain or mountainous areas mostly, and less of them were on hills and coast lines. In water quality, most of places had simple water while the places with salt and sulfur contained water were marked low rate. The temperatures of hot spring water were variable between $25^{\circ}C{\sim}78^{\circ}C$, but the older hot springs were hotter than new ones. After observing the relationship between disposition characteristics and life cycles, the geographical locations and the matter of approach were found as majour influential factors to the life cycles of them. The type of mountainous areas were observed slow progress in life cycle, due to traffic problem, until the road expansion or pavement work were done. Meanwhile, the suburban ones adjacent to big cities were favored by hot spring tourists due to their easy approach and easy traffic. The new born hot springs with such conditions have shown the fast growth. As studied above, since the hot springs were supposed to be for recuperation and vacational, a hot spring with better recreational and accommodational facilities was more favored by tourists than the one with pretty interior decorations. It was because the tour purpose of people has been switched from single purpose to multi one. Thus, the suggestion for activating a declining hot spring and bringing people in them is to develop new and attractive tour resources, expanding the related area, maintaining good quality of water, developing a complex site for long-term tour, developed traffic routs, hot spring festivals, utilizing adjacent tour resources, preparing public water supply system, and assigning as special tour zone.

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