• Journal of Aquaculture
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• v.16 no.3
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• pp.135-141
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• 2003

Physiological responses (cortisol, glucose, lactic acid, osmolality and hematology) of olive flounder (Paralichthys olivaceus) to stressors associated with confinement and subsequent transport were investigated. Specimens were subjected to confinement stress for 3 h, prior to transport for 15 h. Two different size cohorts of the fish, large (839.6$\pm$162.7 g) and small (98.2$\pm$14.8 g), were used. Experimental cohorts of the fish were divided into 3 groups for blood sampling: group A, sampled at the beginning of confinement and 3 h before transport (BT, -3 h), after confinement and at the beginning of transport (BT, 0 h), 3 h after transport had begun (AT, 3 h), and after 15 h transport (AT, 15 h); group B, sampled at BT, 0 h, at AT, 3 h, and at AT, 15 h; and, group C, sampled at AT, 3 h, and at AT, 15 h. In the cohort of large fish, plasma cortisol levels of the A group were increased over time, from 4.2 ng/ml (BT,-3 h), to 92.0 ng/ml (BT, 0 h), 118.5 ng/ml (AT, 3 h) and 105.5 ng/ml (AT, 15 h). A similar pattern was evident in the B group, in which cortisol increased from 47.5 ng/ml (BT, 0 h) to 53.5 ng/ml (AT, 15 h); and, for the C group, in which cortisol increased from 43.5 ng/ml (AT, 3 h) to 71.5 ng/ml (AT, 15 h). Glucose levels of the A group also were significantly increased, from 39.5 mg/dl (BT,-3 h), to 121.0 mg/dl (BT, 0 h),298.0 mg/dl (AT, 3 h) and 260.5 mg/dl (AT, 15 h). Lactic acid levels increased markedly during transport, from less than 1 mmol/L (BT, 0 h) to 12.0 mmol/L (AT, 15 h). Plasma osmolality increased from 405.5 mOsm/kg (BT, -3 h, for group A) to values near 500 mOsM/kg subsequent to confinement and transport. In the small-size cohort, plasma cortisol, glucose, lactic acid and osmolality levels showed similar but less pronounced trends than those observed for the large-size cohort. This research provides baseline data on cortisol, glucose, lactic acid, osmolality and hematological responses to confinement and transport, which should be useful to aquaculturists working with olive flounder and to scientists studying other flatfish species.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.45-47
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• 2002

반도체 소자의 고집적화 및 고속화가 요구됨에 따라 MOSFET 구조의 게이트 절연막으로 사용되고 있는 SiO₂ 박막의 두께를 감소시키려는 노력이 이루어지고 있다. 0.1㎛ 이하의 소자를 위해서는 15Å 이하의 두께를 갖는 SiO₂가 요구된다. 하지만 두께감소는 절연체의 두께와 지수적인 관계가 있는 누설전류를 증가시킨다[1-3]. 따라서 같은 게이트 개패시턴스를 유지하면서 누설전류를 감소시키기 위해서는 높은 유전상수를 갖는 두꺼운 박막이 요구되는 것이다. 그러므로 약 25정도의 높은 유전상수를 갖고 5.2～7.8 eV 정도의 비교적 높은 bandgap을 갖으며, 실리콘과 열역학적으로 안정한 물질로 알려진 HfO2[4-5]가 최근 큰 관심을 끌고 있다. 본 연구에서는 HfO₂ 박막을 실제 소자에 적용하기 위하여 전극 및 열처리에 따른 HfO₂ 박막의 미세구조 및 전기적 특성에 관한 연구를 수행하였다. 이를 위해, HfO₂ 박막을 reactive DC magnetron sputtering 방법으로 증착하고, XRD, TEM, XPS를 사용하여 ZrO₂ 박막의 미세구조를 관찰하였으며, MOS 캐패시터 구조의 C-V 및 I-V 특성을 측정하여 HfO₂ 박막의 전기적 특성을 관찰하였다. HfO₂ 타겟을 스퍼터링하면 Ar 스퍼터링에 의해 에너지를 가진 산소가 기판에 스퍼터링되어 Si 기판과 반응하기 때문에 HfO₂ 박막 형성과 더불어 Si 기판이 산화된다[6]. 그래서 HfO₂같은 금속 산화물 타겟 대신에 순수 금속인 Hf 타겟을 사용하고 반응성 기체로 O₂를 유입시켜 타겟이나 시편위에서 high-k 산화물을 만들면 SiO/sub X/ 계면층을 제어할 수 있다. 이때 저유전율을 갖는 계면층은 증착과 열처리 과정에서 형성되고 특히 500℃ 이상에서 high-k/Si를 열처리하면 계면 SiO₂층은 증가하는 데, 이것은 산소가 HfO₂의 high-k 박막층을 뚫고 확산하여 Si 기판을 급속히 산화시키기 때문이다. 본 방법은 증착에 앞서 Si 표면을 희석된 HF를 이용해 자연 산화막과 오염원을 제거한 후 Hf 금속층과 HfO₂ 박막을 직류 스퍼터링으로 증착하였다. 우선 Hf 긍속층이 Ar 가스 만의 분위기에서 증착되고 난 후 공기중에 노출되지 않고 연속으로 Ar/O₂ 가스 혼합 분위기에서 반응 스퍼터링 방법으로 HfO₂를 형성하였다. 일반적으로 Si 기판의 표면 위에 자연적으로 생기는 비정질 자연 산화막의 두께는 10～15Å이다. 그러나 Hf을 증착한 후 단면 TEM으로 HfO₂/Si 계면을 관찰하면 자연 산화막이 Hf 환원으로 제거되기 때문에 비정질 SiO₂ 층은 관찰되지 않았다. 본 실험에서는 HfO2의 두께를 고정하고 Hf층의 두께를 변수로 한 게이트 stack의 물리적 특성을 살펴보았다. 선증착되는 Hf 금속층을 0, 10, 25Å의 두께 (TEM 기준으로 한 실제 물리적 두께) 로 증착시키고 미세구조를 관찰하였다. Fig. 1(a)에서 볼 수 있듯이 Hf 금속층의 두께가 0Å일때 13Å의 HfO₂를 반응성 스퍼터링 방법으로 증착하면 HfO₂와 Si 기판 사이에는 25Å의 계면층이 생기며, 이것은 Ar/O₂의 혼합 분위기에서의 스퍼터링으로 인한 Si-rich 산화막 또는 SiO₂ 박막일 것이다. Hf 금속층의 두께를 증가시키면 계면층의 성장은 억제되는데 25Å의 Hf 금속을 증착시키면 HfO₂ 계면층은 10Å미만으로 관찰된다. 그러므로 Hf 금속층이 충분히 얇으면 플라즈마내 산소 라디칼, 이온, 그리고 분자가 HfO₂ 층을 뚫고 Si 기판으로 확산되어 SiO₂의 계면층을 성장시키고 Hf 금속층이 두꺼우면 SiO/sub X/ 계면층을 환원시키면서 Si 기판으로의 산소의 확산은 막기 때문에 계면층의 성장은 억제된다. 따라서 HfO₂/Hf(Variable)/Si 계에서 HfO₂ 박막이 Si 기판위에 직접 증착되면, 순수 HfO₂ 박막의 두께보다 높은 CET값을 보이고 Hf 금속층의 두께를 증가시키면 CET는 급격하게 감소한다. 그러므로 HfO₂/Hf 박막의 유효 유전율은 단순 반응성 스퍼터링에 의해 형성된 HfO₂ 박막의 유전율보다 크다. Fig. 2에서 볼 수 있듯이 Hf 금속층이 너무 얇으면 계면층의 두께가 두꺼워 지고 Hf 금속층이 두꺼우면 HfO₂층의 물리적 두께가 두꺼워지므로 CET나 EOT 곡선은 U자 형태를 그린다. Fig. 3에서 Hf 10초 (THf=25Å) 에서 정전 용량이 최대가 되고 CET가 20Å 이상일 때는 high-k 두께를 제어해야 하지만 20Å 미만의 두께를 유지하려면 계면층의 두께를 제어해야 한다.

• Journal of the Korean association of regional geographers
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• v.7 no.1
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• pp.67-82
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• 2001

Recently, local traditions and cultural assets have been rediscovered and developed as resources in local societies of Korea and a great deal of effort has been made to develop event tourism. Based on this renewed interest, this study chose as a case the Wang In Cultural Festival in Kurim-ri, Yongam, and examined the background of the early Wang In Cultural Festival and its evolution up to the present focusing on. the festival program. In Cultural Festival first began as the Wang In Cherry Blossom Festival in 1993 with a budget of 50 million won, and has been developed into a large-scale festival with a budget of 340 million won, attracting 500,000 visitors in 2000. Together with such evolution, there has been a great change in the organization and content of the Festival program. The most important change began in the 1997 which included a religious service for Confucian scholars called 'Chunhyang Grand Festival for Dr. Wang In' as a core program. Since then, festival programs related to Dr. Wang In have greatly increased in number. A decisive change became prominent when the festival promotion system was transferred from the Kunseo Young Men's Association during the early period(1993-1996) to Youngam-gun in 1997. It is true that the Wang In Cultural Festival, which began as a purely regional festival initiated by a non-governmental organization, changed a lot in terms of its scale and program when Youngam-gun emerged as a strong leading group in 1997. However, not enough consideration has been given to institutional devices and procedures that are required for the local culture to take a firm root in the community through the festival. Therefore, in order to solve such fundamental problems, a permanent non-governmental organization is required for festival preparation. In addition, in order to promote overall progress of the community and an increase in the quality of the cultural environment of the local society through the festival, it is necessary to discover and promote recognition of cultural groups in the community.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.609-617
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• 2000

This study is aimed at investigating an effect of HCl gas on selective reduction of NOx over a CuHM and $V_2O_5-WO_3/TiO_2$ catalyst. SCR process is the most effective method to remove NOx, but catalyst can be deactivated by the acidic gas such as HCl gas which is also included in flue gas from the incinerator. In dry condition of flue gas, the CuHM catalyst treated by HCl gas has shown higher NO removal activity than the fresh catalyst. The activity of the catalyst can be restored by treating at $500^{\circ}C$. On the contrary. $V_2O_5-WO_3/TiO_2$ catalyst is obviously deactivated by HCl and the deactivation increases in proportion to the concentration of HCl gas. The deactivated catalyst is not restored to it's original activity by heat treatment for regeneration. In wet flue gas stream, the CuHM catalyst has shown lower activity than fresh catalyst and $V_2O_5-WO_3/TiO_2$ catalyst was severely deactivated by HCl treatment. The activity loss of catalysts are mainly due to the decrease of Br$\ddot{o}$nsted acid site on the catalyst surface by $NH_3$ TPD. The change of BET surface area of CuHM catalyst after the reaction isn't observed but $V_2O_5-WO_3/TiO_2$ catalyst is observed. The amount of $Cu^{{+}{+}}$ and $V_2O_5$ is decreased after the reaction. From these results, it is expected that CuHM catalyst should be better than $V_2O_5-WO_3/TiO_2$ catalyst for its application to the incineration of flue gas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.163-173
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• 2007

Lipid peroxidation is one of the main manifestations of oxidative damage and has been found to play an important role in the toxicity and carcinogenesis of many carcinogens. This study was carried out to determine the effects of vitamin C on lipid contents and fatty acid compositions of serum and liver in male rats treated with radiation or aflatoxin $B_1\;(AFB_1)$. Six week-old male Sprague-Dawley rats were randomly divided into 7 groups; control group, radiation exposed group, $AFB_1$ treated group, X-ray and $AFB_1$ co-treated group. Three groups, except control group, were each further divided into vitamin C administered group and not administered groups. For this study, vitamin C was injected with 10 mg/kg of body weight by intraperitoneal injection and 1 hr later, 0.4 mg/kg of $AFB_1$ was injected by the same method. These administrations were repeated every 3 days over a period of 15 days. Only one time, X-ray was irradiated on whole liver with 1,500 cGy. Then vitamin C and AFB1 were administered by the same level and same method described above. On the 16th day of treatments, the animals were sacrificed. From the analysis of the serum lipid patterns, significant decrease (p<0.01) in triglyceride (TG) and total cholesterol levels were observed in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). In liver lipids, the levels of free cholesterol and total cholesterol were also decreased in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). The levels of serum free cholesterol and hepatic TG were not significantly different among all groups according to vitamin C administrations. The high density lipoprotein (HDL)-cholesterol level of serum was significantly (p<0.01) increased while the low density lipoprotein (LDL)-cholesterol level was decreased in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). In the phospholipid fatty-acid compositions of serum and liver tissue, group 3, 5 and 7 showed an increase in polyunsaturated fatty-acid (PUFA) but a decrease in saturated fatty acid (SFA) when compared to the control group. The composition ratio of fatty acid varied according to vitamin C administration. These results suggested that vitamin C has partly suppressive effects on lipid contents and fatty acid composition of serum and liver in rats treated by radiation and $AFB_1$.

• The Korean Journal of Financial Studies
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• v.3 no.1
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• pp.233-265
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• 1996

We examine the impact of public and private information on price movements using the thirty DJIA stocks and twenty-one NASDAQ stocks. We find that the standard deviation of daily returns on information days (dividend announcement, earnings announcement, insider purchase, or insider sale) is much higher than on no-information days. Both public information matters at the NYSE, probably due to masked identification of insiders. Earnings announcement has the greatest impact for both DJIA and NASDAQ stocks, and there is some evidence of positive impact of insider asle on return volatility of NASDAQ stocks. There has been considerable debate, e.g., French and Roll (1986), over whether market volatility is due to public information or private information-the latter gathered through costly search and only revealed through trading. Public information is composed of (1) marketwide public information such as regularly scheduled federal economic announcements (e.g., employment, GNP, leading indicators) and (2) company-specific public information such as dividend and earnings announcements. Policy makers and corporate insiders have a better access to marketwide private information (e.g., a new monetary policy decision made in the Federal Reserve Board meeting) and company-specific private information, respectively, compated to the general public. Ederington and Lee (1993) show that marketwide public information accounts for most of the observed volatility patterns in interest rate and foreign exchange futures markets. Company-specific public information is explored by Patell and Wolfson (1984) and Jennings and Starks (1985). They show that dividend and earnings announcements induce higher than normal volatility in equity prices. Kyle (1985), Admati and Pfleiderer (1988), Barclay, Litzenberger and Warner (1990), Foster and Viswanathan (1990), Back (1992), and Barclay and Warner (1993) show that the private information help by informed traders and revealed through trading influences market volatility. Cornell and Sirri (1992)' and Meulbroek (1992) investigate the actual insider trading activities in a tender offer case and the prosecuted illegal trading cased, respectively. This paper examines the aggregate and individual impact of marketwide information, company-specific public information, and company-specific private information on equity prices. Specifically, we use the thirty common stocks in the Dow Jones Industrial Average (DJIA) and twenty one National Association of Securities Dealers Automated Quotations (NASDAQ) common stocks to examine how their prices react to information. Marketwide information (public and private) is estimated by the movement in the Standard and Poors (S & P) 500 Index price for the DJIA stocks and the movement in the NASDAQ Composite Index price for the NASDAQ stocks. Divedend and earnings announcements are used as a subset of company-specific public information. The trading activity of corporate insiders (major corporate officers, members of the board of directors, and owners of at least 10 percent of any equity class) with an access to private information can be cannot legally trade on private information. Therefore, most insider transactions are not necessarily based on private information. Nevertheless, we hypothesize that market participants observe how insiders trade in order to infer any information that they cannot possess because insiders tend to buy (sell) when they have good (bad) information about their company. For example, Damodaran and Liu (1993) show that insiders of real estate investment trusts buy (sell) after they receive favorable (unfavorable) appraisal news before the information in these appraisals is released to the public. Price discovery in a competitive multiple-dealership market (NASDAQ) would be different from that in a monopolistic specialist system (NYSE). Consequently, we hypothesize that NASDAQ stocks are affected more by private information (or more precisely, insider trading) than the DJIA stocks. In the next section, we describe our choices of the fifty-one stocks and the public and private information set. We also discuss institutional differences between the NYSE and the NASDAQ market. In Section II, we examine the implications of public and private information for the volatility of daily returns of each stock. In Section III, we turn to the question of the relative importance of individual elements of our information set. Further analysis of the five DJIA stocks and the four NASDAQ stocks that are most sensitive to earnings announcements is given in Section IV, and our results are summarized in Section V.

• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.27-41
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• 1999

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-30Pd-10Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at 350-$550^{\circ}C$ Age-hardening characteristic of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, energy dispersed spectra and electron probe microanalysis. Principal results are as follows ; Maximum hardening occured in two co-phases of ${\alpha}_2$ + PdCu In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase($L1_o$ type) and an Ag-rich ${\alpha}_2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu redered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}{\to}{\alpha}_1+PdCu{\to}{\alpha}_2+PdCu$ at Pd/Cu = 3 Pd element of Ag-Pd-Cu alloy is more effective dental alloy on anti-corrosion and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.21-35
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• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of the Korean Institute of Landscape Architecture
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• v.17 no.1
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• pp.43-54
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• 1989

In recent years plants have increasingly become in inferior part of the interior designing of large buildings. In 28 large buildings selected at random in Seoul City have been subjected to studies on utilization status of fille interior landscape plants. The results obtained were as follows. 1. Plant class found in Interior of large buildings were 59 class, especially Dracaena were the most predominent plants among them, and then comes Monstera, Phiodendron, Schefflera, and Washingtonia in that order. 2. The most abundant ornamental plant cultivars were Monstera adansoii(Monstera perutusa cv.), and then comes Schefflera arboricora(Schefflera Hong Kong cv.), Washingionia rubusta (Washingtonia palm). Rhapis excelsa, and Diffenbachia(Hawaii Snow cv.) in that order. 3. Foliage plants among the interior landscape plants showed 99.5 percent and Woody plants and Bonsai plants showed each 0.4, 0.1 percent. 4. Climbing foliage plants found in 28 large building observed For the present study were 9 cultivar, and the most abundant plants were Hedera (pittsburgh cv.) and Epipremnum (Marble Queen cv.) pl anted to clustered planting. 5. A majority of plants used to plastic pot, and most of 71an1s place on the floor. 6. Height of plants ranging less then 50cm were more frequently found, but ranging from 50cm to 2.0m were 4.3 percent and the most predominent height of plants were Canariensis showed 4m in the large buildings. 7. Interior light intensity in large building were shortage, therefore artificial lamp for formal growing needed to be equipped. 8. Purpose growth of interior plants were to in order visitors. 9. 7he superintendents prefered to used pot-stand. 10. The most important environment factor for plant growing were light, humidity, and water.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.450-465
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• 2017

This study was conducted to characterize the amylose and protein contents of 4,948 rice landrace germplasm using the NIRS model developed in the previous study. The average amylose content of the germplasm was 20.39% and ranged between 3.97 and 37.13%. The amylose contents in the standard rice were 4.99, 18.63 and 20.55% in Sinseonchal, Chucheong and Goami, respectively. The average protein content was 8.17% and ranged from 5.20 to 17.45%. Protein contents in Sinseonchal, Chucheong and Goami were 6.824, 6.869 and 7.839%, respectively. A total of 62% germplasm were distributed between 20.06% and 27.02% in amylose content. Germplasm of 81.60% represented protein content of 6.78-9.75%. The distinguishable ranges of amylose contents according to origin were 16.58-20.06% in Korea, 20.06-23.25% in Japan, 23.25-27.02% in North Korea, and 27.02-37.13% in China. In the protein content, approximately 30% of Chinese resources ranged from 9.75 to 17.45%, whereas less than 10% were detected in other origin accessions. Fifty resources were selected with low and high amylose ranging from 3.97-6.66% and 30.41-37.13%, respectively. Similarly, fifty resources were selected with low and high protein ranging from 5.20-6.09% and 13.21-17.45%, respectively. Landraces with higher protein could be adapted to practical utilization of food sources.