• Korean Journal of Weed Science
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• v.18 no.3
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• pp.205-213
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• 1998

This experiment was carried out to produce herbicide resistant potatoes hawing only chimeric phosphinothricin acetyltransferase (PAT) genes without using antibiotic selectable marker. The pDY502 vector having only PAT gene was reconstructed for transformation of potato. The reconstructed vector was introduced to Agrobacterium tumefaciens MP90 disarmed, and they were used for potato transformation. Hormonal requirement for plant regeneration from leaves and stem explants of potato was investigated. From this experiment, MS medium treated with IBA 0.1 mg/L + BA 0.5 mg/L was the best for potato regeneration, and the ratio of shoot regeneration was 54% for leaf and 46% for stem in that condition. For transformation, explants of potato leaves and stems were cocultured with A. tumefaciens MP90 containing reconstructed vector harvoring only PAT gene. When the potato explants were placed on various concentrations of bialaphos and all the potato explants were dead on medium with over 5.0mg/L bialaphos. By this selection methods, the explants cocultured with Agrobacterium produced the putative transgenic shoots on medium with 5mg/L bialaphos treatment after 3-4 weeks. Second selection was performed by transferring the shoot tips of putative transgenic to medium containing 20mg/L of bialaphos. The shoot tips grew well on the second selection medium, indicating the production of successful transgenic plants. But normal shoots were dead in same cytotoxic medium. Incorporation of the PAT gene into transgenic potatos were confirmed by PCR analysis of DNA and Southern hybridization. These results show that the PAT gene can serve as a selectable marker and herbicide resistant genes for transformation of potato.

• Korean Journal of Microbiology
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• v.51 no.1
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• pp.7-13
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• 2015

Hydrotrope-combined copper (HCC) is a copper ($Cu^{2+}$)-based algicide, which is combined with a hydrotrope that keeps copper ion in solution to improve performance. This study assessed the growth inhibition effect of HCC against Microcystis aeruginosa which is one of the most common toxic cyanobacterium in eutrophic freshwater environment. Various HCC doses, ranging from 5.5 to $550{\mu}g/L$ as $Cu^{2+}$, were applied to either BG-11 or 1/4 diluted medium with low- or high-inoculum density of M. aeruginosa. Growth inhibition was monitored based on a decrease in chlorophyll-a content in culture medium during the incubation. Results showed that HCC significantly inhibited the growth of M. aeruginosa in a dose-dependent manner. In case of 1/4 diluted BG-11 medium, HCC dose as low as $5.5{\mu}g$ $Cu^{2+}/L$ completely inhibited the production of chlorophyll-a by M. aeruginosa. It was found that HCC did not induce any significant release of microcystin-LR from M. aeruginosa. Acute toxicity of HCC was tested using Daphnia magna, and the 24-h $EC_{50}$ value was 0.30 mg/L as $Cu^{2+}$ which was much higher than the actual inhibition dose. Ames test was performed using Salmonella enterica serovar Typhimurium TA100, and HCC showed no increase in the number of revertant colonies. The result suggested that HCC does not have any mutagenic potential in the aquatic environment. In addition, no genotoxic effect of HCC was also confirmed based on the SOS ChromoTest using Escherichia coli PQ37. Therefore, HCC could be used as a relatively safe and effective pre- and post-treatment agent to control hazardous algal blooming in aquatic environments.

• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.51-67
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• 1996

There are three main rice-growing regions in the United States: the prairie region along the Mississippi River Valley in eastern Arkansas; the Gulf Coast prairie region in southwestern Louisiana and southeastern Texas; and the Central Valley of California. The Central Valley of California is producing about 23% of the US rice(Fig. 1). In California. most of the crop has been produced in the Colusa, Sutter, Butte, Glenn Counties of the Sacramento Valley since 1912, when rice was commercially grown for the first time in the state(Fig. 2). Roughly speaking, the average annual area sown to rice in California is about 300,000 acres to 400,000 acres during the last forty years(Fig. 3). California rice is grown under a Mediterranean climate characterized by warm, dry, clear days, and a long growing season favorable to high photosynthetic rates and high rice yields. The average rice yield per acre is probably higher in California than in any other rice-growing regions of the world(Fig. 4). A dependable supply of irrigation water must be available for a successful rice culture. Most of the irrigation water for California rice comes from the winter rain and snow-fed reservoir of the Sierra Nevada mountain ranges. Less than 10 percent of rice irrigation water is pumped from wells in areas where surface water is not sufficient. It is also essential to have good surface drainage if maximum yields are to be produced. Rice production in California is highly mechanized, requiring only about four hours of labor per acre. Mechanization of rice culture in California includes laser-leveler technology, large tractors, self-propelled combines for harvesting, and aircraft for seeding, pest control, and some fertilization. The principal varieties grown in California are medium-grain japonica types with origins from the cooler rice climates of the northern latitudes (Table 1). Long-grain varieties grown in the American South are not well adapted to California's cooler environment. Nearly all the rice grown recently in California are improved into semidwarf varieties. Choice of variety depends on environment, planting date, quality desired, marketing, and harvesting scheduling. The Rice Experiment Station at Biggs is owned, financed, and administered by the rice industry. The station was established in 1912, as a direct result of the foresight and effort of Charles Edward Chambliss of the United States Department of Agriculture. Now, The station's major effort is the development of improved rice varieties for California.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.214-219
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• 2010

In order to evaluate the benefits of global warming on the double cropping with staple crops in North-Korea, four aspects such as the increasing rate of air temperature, the wintering temperatures for winter crops, the causing temperature of cool injury to rice and the securing of accumulated temperature for the double cropping in the different agricultural climate zones were analyzed by comparing the differences between the past 22 years from 1973 to 1994 and the recent 5 years from 2002 to 2006. The warming rate in recent daily mean air temperature of $8.96^{\circ}C$ in North Korea was higher by $0.64^{\circ}C$ than that in the past with large regional variations ranging from $1.06^{\circ}C$ in Samjiyeon of northern inland semi-alpine zone to $12.26^{\circ}C$ in Jangjeon of east central coastal zone. With the accumulated temperatures of more than $3,150^{\circ}C$ and $2,650^{\circ}C$, it was possible to apply the double cropping patterns with winter wheat and for cropping patterns with spring potato, respectively, to the whole region except for the northern inland semi-alpine zone. However, the wintering temperature higher than $-15^{\circ}C$ of average daily minimum air temperature of January, cropping patterns were impossible to northern inland semi-alpine zone and most regions of the northern mountainous zone. The days passed by below $17^{\circ}C$ in daily mean air temperature, causing the spikelet sterility at meiotic stage of rice in July, were a lot recorded from 21 to 29 days in northern inland semi-alpine zone and from 2 to 10 days in east-northern coastal zone, respectively. Therefore, a reasonable utilization of heat / temperature resources would relieve the limiting factors in double cropping for stable production of staple crops in North-Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.1
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• pp.30-39
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• 2020

A new silicate coating technology was developed which reduces the impact of dust and loosening during seeding compared to existing silicate-coatings (Seed/Si/Zeolite), and therefore can lower the production costs of rice cultivation. In this method, 100 g of rice seed is coated with 18 mL of liquid silicic acid and then dressed with a mixture containing 80 g of dolomite and 5 g of iron. To determine the most effective method of application and ensure that seedlings developed healthily, a series of experiments were carried out. Infected seeds scattered in seedling boxes and pots (soil and hydroponic) were coated dry, without disinfection. In comparison to the seed which were not treated with the silicate-coating, the new seed (A) were 1.84 times heavier in weight, and were also improved in terms of coating strength and coating color. Compared to the seedlings grown from the non-coated seed, those grown from the new silicate-coated seed were of significantly higher quality (weight/length) and had erect, dark greenish leaves, which are ideal plant characteristics. This was most likely due to increased silicate uptake. The symptoms of bakanae disease in the non-coated seed peaked after 38 days to 54.2%, whereas the control value was 68.8% in the new silicate-coated seed (A). In the infected seedlings grown from the new silicate-coated rice seed, subnormal macro-conidia, namely, a sickle shape spore without a septum; a straight oblong shape spore without a septum and with a thick cell wall; and inter-septal necrosis of a normal spore were detected. It is believed that the strong alkalinity of silicic acid have acted as unfavorable conditions for pathogenicity. In seedlings grown from the new silicate coated rice seed under hydroponic conditions without nutrients, normal root activity and growth was maintained without leaf senescence. Therefore, it was possible to reduce the rate of fertilization. In the future, a new silicate-coated rice seed was required for the study of minimal nutrition for anti-aging of seedlings.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.503-512
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• 2020

To enhance the usability of puffed rice, we evaluated the quality characteristics and antioxidant activity of vinegar made with puffed rice and lemon balm. First, puffed rice containing lemon balm extracts was fermented for alcohol production. The alcoholic fermented liquid was adjusted to an alcohol content of 6% and an initial acidity of 2% for vinegar fermentation. The pH and alcohol content of the lemon balm vinegar decreased overall as fermentation progressed. The total acidity was 5.20±0.01% (2.0% lemon balm) to 5.80±0.01% (0.0% lemon balm) on the 15th day of fermentation, and the total acidity was slightly lower as the amount of added lemon balm was increased. Citric, succinic, and acetic organic acids were detected in the vinegar and the acetic acid content was highest at 4.81% to 5.37% on the 15th day of fermentation. We found that the total polyphenol and total flavonoid content of the lemon balm vinegar increased as we added lemon balm, and the content on the 15th day of fermentation was 179.4±4.5 (0.0% lemon balm) - 340.8±2.6 mg/kg (2.0% lemon balm) and 1.5±0.3 (0.0% lemon balm) - 31.7±0.3 mg/kg (2.0% lemon balm), respectively. The higher the amount of lemon balm added, the higher the DPPH radical scavenging activity, the FRAP (reducing power), and the ABTS radical scavenging activity. Moreover, those activities after 2.0% lemon balm treatment were 82.99±0.61%, 1.08±0.01 abs., and 87.67±0.68%, respectively, on the 15th day of fermentation. These results suggest that vinegar with added lemon balm may be used as an antioxidant agent.

• Journal of the Korean Society for Library and Information Science
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• v.28
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• pp.301-390
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• 1995

In this paper, I intended to study the policy executed by the king Sungjong(성종), the ruler of the early Chosun(조선) Dynasty, for the purpose of the training for the literary scholars under the diplomatic necessity and from his own interest in literature, and the compilation and the publication of anthologies of the famous civil officials in those days under the influence of this policy. The overall findings of the study can be summarized as follows : 1. Sungjong was comparable with the Sejong(세종) in his studiousness and especially, he was very interested in literature. He composed verses personally, showed them to his civil officials and demanded their poems in response to his own ones. Futhermore, he executed steadily the institutions of Eung-je(응제), Kaw-si(과식) and Weol-kwa(월과) that demanded creative writings from his civil officials. The purpose of these institutions which was propelled by the king Sungjong was the training for the literary scholars under the diplomatic necessity. 2. Chosun Dynasty exchanged envoys with Myeong(명) Dynasty during the time of the king Sungjong as many as 100 times. The training for the excellent literary scholars was nationally urgent problem because the competent literary scholars were needed whenever Myeong Dynasty dispatched the envoys to Chosun Dynasty. Eung-je, Kwa-si and Weol-kwa were executed from practical demand and 1 - 3 persons at the minimum, 60 - 70 persons at the maximum took part in this institution at a time. This means that 60 - 70 literary works were produced at a time. Therefore, the steady execution of Eung-je, Kwa-si and Weol-kwa inevitably resulted in mass production of literary works. 3. The king Sungjong instructed his civil officials to compile the anthologies of the then representative civil officials as a means to encourage literary compositions, read it himself and took actions to publish them at the expense of government. There were six anthologies compiled and published under this policy of the king Sungjong, Kang Heui­maeng's Sasukjejib(강희맹, 사숙제집), Shin Suk-ju's Bohanjaejib(신숙단, 보한제집), Kim Su-on's Shikujib (김수온, 식우집), Choe Hang's Taeheojeongjib(최항, 태허정집), Seo Keo-jeong's Sagajib (서거정, 사가집), Lee Seok-hyeong's Jeoheonjib(이석형, 저헌집). Yu Ho-in's Noekyejib(유호인, 뇌계집+CZ48), Lee Seung-so's Samtanjib(이승소, 삼탄집), Kim Jong-jik's Jeompiljaejib(김종직, 점필제집) of three were examined by the king Sungjong, but published later because of the death of the king. 4. jeompiljaejib was compiled by order of the king Sungjong and passed Eulram (을람 : king reads an anthology personally) which contained Joeuijemoon(조의제문) that criticized the king Sejo(세조) who had usurped a throne. The recording of Joeuijemoon became an issue in process of Muosahwa(무오사화), and it was ordered that the printing blocks should be broken and the published books should be collected and be burnt up. These procedures destroyed the social atmosphere that people considered it an honor writing literary compositions, compiling and publishing anthologies thanks to the steady efforts of the king Sungjong. 5. It had an important effect on the compilation and the publication of anthologies after that, breaking the printing blocks, collecting and burning up the pulished books of Jeompiljaejib because of recording of Joeuijemoon. Namely, it got universalized to delete compositions that can cause problems in the future as well as the parts related to political issue, from the objects of recording. Such tendency became one of the important principles of the anthological compilation after that.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.90-96
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• 2010

In this study, the anti-oxidant, anti-tumorigenic, anti-hypertensive, anti-thrombic, anti-diabetic, and anti-inflammatory properties of 18 different species of genus Pleurotus were investigated. In addition, the amino acid, $\beta$-glucan, and polyphenol content were also measured. All species contained more than 20 mg% of polyphenol with the highest contents found in Pleurotus cornucopiae var. citrinopileatus (yellow pleurotus) ($39.13{\pm}0.82\;mg%$). The $\beta$-glucan contents was also the highest in yellow Pleurotus ($37.67{\pm}0.22%$) followed by Won-Hyeong1 (C, $28.75{\pm}0.61%$) and Jang-an PK (A, $27.95{\pm}0.33%$). The yellow Pleurotus exhibited the highest antioxidant activity as assessed by the DPPH scavenging rate with an $IC_{50}$ value of $2.94{\pm}0.44\;mg/mL$. Ethanol extracts from the yellow Pleurotus treated at 1% concentration showed cytotoxic activity up to 36.9% in the human embryonic kidney 293T cell lines. The yellow Pleurotus also showed the highest inhibitory effects on ACE activity ($60.52{\pm}0.2%$). Finally, the yellow Pleurotus exhibited anti-diabetic and anti-inflammatory properties as shown by inhibition of $\alpha$-amyloglucosidase activity ($50.5{\pm}0.8%$) and nitric oxide production ($68.4{\pm}0.3%$). Taken together, our data indicate the yellow pleurotus is a promising functional food ingredients.

• Applied Biological Chemistry
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• v.3
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• pp.25-48
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• 1962

The polysaccharide C prepared from gum tragacanth powder (U. S. P. grade) by the precipitation method with 85% ethanol was a neutral polysaccharide, $[{\alpha}]^{30}_D-72.2$. The polysaccharide C consisted of L-rhamnose, D-xylose, L-arabinose and D-galactose in the molar ratio 2:1:17:9 (Table 1, 2, 3, ). The polysaccharide C was methylated with dimethylsulphate and 40% NaOH, and Purdies regent. The hydrolyzate of fully methlated product ($[{\alpha}]^{22}_D-102$ in chloroform, the methoxy content 40.6%) was composed of 2, 3, 5-tri-O-methyl-L-arabofuranose (I), 3,4-di-O-methyl-L-rhamnopyranose (II), 2,3-di-O-methyl-D-xylose (III), 2,3,4-tri-O-methyl-D-galactopyranose (IV), 2,4-di-O-methyl-L-arabopyranose (?), 2,4-di-O-methyl-D-galactose(VI), 2-O-methyl-D-arabinose (VII), and L-arabopyranose(VIII) (Table 4, 5, and Fig. 4). The first partial hydrolysis (A) of the polysaccharide C with 0.05N-HCl for 4.5 hours at $80-85^{\circ}C$ released only L-arabinose: the second hydrolysis (B) with 0.1N-HCl for 5 hours at $80-85^{\circ}C$, L-arabinose and D-galactose; and the third hydrolysis (C) with 0.3N-HCl at $90-95^{\circ}C$ in sealed tube, L-rhamnose, D-xylose, L-arabinose and D-galactose. From the unhydrolyzate A' were found L-rhamnose, D-xylose, L-arabinose, and D-galactose; from B' L-rhamnose, d-xylose, L-arabinose and D-galactose; and from C' D-xylose and D-galactose respectively (Table 6). The periodate consumption and formic acid production of the polysaccharide C were measured at various time intervals. After 120 hours periodat was consumed by 1.23 mole per $C_5H_8O_4$ and formic acid was produced 0.78 mole per $C_5H_8O_4$ (Table 7). Although a definite chemical structure for this polysaccharide C may not be formulated, experimental data, especially, from methylation, partial hydrolysie and determination of its molar ratio, and periodate analysis showed that the polysaccharide C is a highly branched polysaccharide and would be constructed of galactoaraban as a main chain residue and L-arabofuranose, D-galactopyranosyl $(1{\rightarrow}1)$-L-arabofuranose, D-xylopyranosyl $(1{\rightarrow}2)$-L-rhamnopyranosyl $(1{\rightarrow}1)$-L-arabofuranose, and L-rhamnopyranosyl $(1{\rightarrow}1)$-arabofuranose, and D-galactopyranosyl-$(1{\rightarrow}2)$-L-arabopyranosyl-$(1{\rightarrow}1)$-I-arabofuranose as a branch chain or end group (page 21).

• Archives of design research
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• v.2 no.1
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• pp.43-62
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• 1989

The luxury is the expression of human being's ornament instinct. In this study, in order to grasp the moulding system of the Korean's personal ornaments, the process of luxury prohibition was reviewed to search for to which direction the ornaments developed in the frame of the prohibited style connected closely to the character of the personal ornaments. The proiod was fixed from the old society to the late Chosun dynasty era. The beginning of the luxury in Korea seems to be the start of the luxury burial at the time of funeral in the age of Koguryo., In the era of Koguryo, 10th year of King Dongmyung (B. C. 28), in the era of Baekje, 27th year of King Koi(260), the prohibition of dress regulation and the style of dress were conducted. The prohibition of personal ornaments in Silla was started from King Bup:Heung, and in the 9th year of King Heung-Duk, the prohibition was conducted in order to correct the luxury of the nobles and set up the social discipline. In the 11 th of King Il-Sung-Ni-Sa-Kum, the use of gold, silver and jade was prohibited in the civilian circles. The prohibition of Silla was succeeded to Koryo era, and in the 7th year of King Kwangjong(956), the system of Baekgwan Gongbok(uniform for government officials) was set up, and the system of Sasek Gongbok(four color official uniform) was set up in the 11 th year of the same King, and the prohibition of the personal ornaments such as crown and band is considred to have been conducted. The prohibition of gold and silver was conducted in the first year of King Sungjong(982), and in the 4th year of King Chungryul(l260), the order of wearing the dress and hat in accordance with the Yusan dynasty and the Mongolian customs were widely circulated in the royal court and vivilian circles. The strong influence of Mongolia made the taste of the traditional personal ornaments laste. The personal ornaments were used for the nobles until the age of the Unified Sillar but even the common people could use them in case they were rich, and such a circumstances made the use of foreign goods inflated. The prohibition of Koryo era was aimed at the prohibition of the foreign goods of luxury, and the classification of the social status.In the age of Chosun Dynasty, the production of gold and silver was feeble indeed but the oute reason of the prohibition was to eradicate the luxurious tendency, elevate the custom of eradicate the luxurious tendency, elevate the custom of thrift, and moreover, the gold, silver and jade were no the products of Korea and the prohibition was conducted but the true reason was afor the tribute tt China and the classification of status. The prohibition of Chosun dynasty was conducted first in the June of the 3rd year of King Taejo The major contents of prohibition was no use of gold, silver and jade, coral, agate, amber, etc. of th, wives of the Dang-Sang-Kwan (Court Nobleman) or their sons and daughters, and the same pheno menon was common even at the time of marriage. The people engaged in the secret trade there of wert beheaded. The personal ornaments in the prohibition were the pendent trinket, Binyo (crossbar) ceremonial ornamental hat, ring, earring, ornamental knife, hat string, hat ornament, belt, etc. Thl luxurious marriage expenses out of the luxury was severe, and lose of the marriageable age because 0 non-preparing the marriage goods was the national evil. The prohibition oC luxury was hard to bt kept to the nobles or rich people, the same as old days and present days. The prohibition of th{ luxury and personal ornaments of Korea had nothing to do with the commons, and it was limited tc the nobles and rich people. The prohibition was aimed to cultivating the custom of frugality by eradicating the luxurious atmosphere, but it was chiefly due to the tribute to the China and tht discrimination of the. status. We can say that the recent personal ornament was the flower of handi craft industry bloomed in the prohibition and regulation.