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History and Archives : Colleagues or Strangers? (역사학과 기록학 학문의 인연, 학제의 괴리)

  • OH, Hang-Nyeong
    • The Korean Journal of Archival Studies
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    • no.54
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    • pp.179-210
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    • 2017
  • By redefining the concept of history, my colleagues and I have reformed our department in terms of curriculum and faculty members. This paper is a report of some of the conclusions that we have obtained from this procedure. Despite a long relationship, two disciplines do not seem to match or complement each other in the Korean education system. We believe that this is due to the fact that the Department of Korean History has focused on "national history (NH)." By conferring a privilege on NH, persons, families, societies, regions, and others were removed from NH. To make matters worse, a biased view that history is just an interpretation has prevailed, and the empiricism of history was weakened, which brought about an indifference in keeping records and archives. In East Asia, "history" means both modern history and archives. The concern about the authenticity of records did not come from H. Jenkinson or L. Duranti, and not even from the electronic environment or the Public Records Act of 1998. Key concepts such as records, documents-archives, manuscripts, authenticity, compilation-appraisal, arrangement, and description are different from their signifiant but are same or similar to their $signifi{\acute{e}}$. In case of "provenance" and "original order," they are used in education and practice in the traditional archives. History includes the recording, archiving, and the story or historiography of an event. In this context, the Department of Korean History should contain a more archives-oriented curriculum and select an archival-trained faculty. On the other hand, the department has accumulated long-term experience with appraisal and description of records; thus, archival science should absorb the criticism of the material. History will be shaken without the help of archives, while archives will lose their root without history. We are at the point in which we need to be reminded why we want to be a historian or an archivist, and for this, the more colleagues, the better.

Coarse Woody Debris (CWD) Respiration Rates of Larix kaempferi and Pinus rigida: Effects of Decay Class and Physicochemical Properties of CWD (일본잎갈나무와 리기다소나무 고사목의 호흡속도: 고사목의 부후등급과 이화학적 특성의 영향)

  • Lee, Minkyu;Kwon, Boram;Kim, Sung-geun;Yoon, Tae Kyung;Son, Yowhan;Yi, Myong Jong
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.40-49
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    • 2019
  • Coarse woody debris (CWD), which is a component of the forest ecosystem, plays a major role in forest energy flow and nutrient cycling. In particular, CWD isolates carbon for a long time and is important in terms of slowing the rate of carbon released from the forest to the atmosphere. Therefore, this study measured the physiochemical characteristics and respiration rate ($R_{CWD}$) of CWD for Larix kaempferi and Pinus rigida in temperate forests in central Korea. In summer 2018, CWD samples from decay class (DC) I to IV were collected in the 14 forest stands. $R_{CWD}$ and physiochemical characteristics were measured using a closed chamber with a portable carbon dioxide sensor in the laboratory. In both species, as CWD decomposition progressed, the density ($D_{CWD}$) of the CWD decreased while the water content ($WC_{CWD}$) increased. Furthermore, the carbon concentrations did not significantly differ by DC, whereas the nitrogen concentration significantly increased and the C/N ratio decreased. The respiration rate of L. kaempferi CWD increased significantly up to DC IV, but for P. rigida it increased to DC II and then unchanged for DC II-IV. Accordingly, except for carbon concentration, all the measured characteristics showed a significant correlation with $R_{CWD}$. Multiple linear regression showed that $WC_{CWD}$ was the most influential factor on $R_{CWD}$. $WC_{CWD}$ affects $R_{CWD}$ by increasing microbial activity and is closely related to complex environmental factors such as temperature and light conditions. Therefore, it is necessary to study their correlation and estimate the time-series pattern of CWD moisture.

Biological Activity of Viola mandshurica Fermented with Bacillus methylotrophicus CBMB205 and Leuconostoc pseudomesenteroides NRIC1777 (미생물 분리주를 이용한 제비꽃 발효액의 생리활성 변화)

  • Lee, Ji-Young;Oh, Su-Bin;Choi, Nack-Shick;Park, Yong-Woon;Kang, Dae-Ook
    • Journal of Life Science
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    • v.29 no.2
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    • pp.239-247
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    • 2019
  • The aim of this study was to improve the efficacy and functionality of Viola mandshurica (VM). A water suspension of VM power was fermented for 72 hr with Bacillus methylotrophicus CBMB205 (BM) and Leuconostoc pseudomesenteroides NRIC1777 (LP) isolated from kimchi. The antioxidant activity and reducing power of fermented VM, its total phenolic and flavonoid compounds, as well its inhibitory activity on ${\alpha}$-amylase, ${\alpha}$-glucosidase, and pancreatic lipase were determined and compared to those of non-fermented VM (NVM), a negative control. The total phenolic and flavonoid compounds of VM fermented with BM and LP were higher than those of NVM by 1.4, 1.17, and about 3 times. There was no difference in 2, 2'-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity between fermented VM and NVM. However, there was a 2.1- and 1.6-fold increase in 2, 2'-azino-bis-(3-ethylbenzothzoline-6-sulfonic acid) (ABTS) radical scavenging activity in VM fermented with BM and LP, respectively. The reducing power of BM was 1.6 times as high as NVM, but no significant difference was found between LP and NVM. Fermented VM's inhibitory activity on ${\alpha}$-amylase, ${\alpha}$-glucosidase, and pancreatic lipase was much higher than that of NVM. Fermenting VM with BM was superior to fermenting it with LP, except flavonoid content. Taken together, VM fermented with BM could be used as a functional food and as an additive to cosmetics.

Development and Validation of an Analytical Method for Quinoxyfen in Agricultural Products using QuEChERS and LC-MS/MS (QuEChERS법 및 LC-MS/MS를 이용한 농산물 중 살균제 Quinoxyfen의 잔류시험법 개발 및 검증)

  • Cho, Sung Min;Do, Jung-Ah;Lee, Han Sol;Park, Ji-Su;Shin, Hye-Sun;Jang, Dong Eun;Choi, Young-Nae;Jung, Yong-hyun;Lee, Kangbong
    • Journal of Food Hygiene and Safety
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    • v.34 no.2
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    • pp.140-147
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    • 2019
  • An analytical method was developed for the determination of quinoxyfen in agricultural products using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted with 1% acetic acid in acetonitrile and water was removed by liquid-liquid partitioning with $MgSO_4$ (anhydrous magnesium sulfate) and sodium acetate. Dispersive solid-phase extraction (d-SPE) cleanup was carried out using $MgSO_4$, PSA (primary secondary amine), $C_{18}$ (octadecyl) and GCB (graphitized carbon black). The analytes were quantified and confirmed by using LC-MS/MS in positive mode with MRM (multiple reaction monitoring). The matrix-matched calibration curves were constructed using six levels ($0.001-0.25{\mu}g/mL$) and the coefficient of determination ($R^2$) was above 0.99. Recovery results at three concentrations (LOQ, 10 LOQ, and 50 LOQ, n=5) were in the range of 73.5-86.7% with RSDs (relative standard deviations) of less than 8.9%. For inter-laboratory validation, the average recovery was 77.2-95.4% and the CV (coefficient of variation) was below 14.5%. All results were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL 40-1993, 2003) and Food Safety Evaluation Department guidelines (2016). The proposed analytical method was accurate, effective and sensitive for quinoxyfen determination in agricultural commodities. This study could be useful for the safe management of quinoxyfen residues in agricultural products.

Comparison of the Rate of Demineralization of Enamel using Synthetic Polymer Gel (합성 폴리머 겔의 법랑질 탈회 속도 비교)

  • Lee, June-Hang;Shin, Jisun;Kim, Jongsoo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.46 no.2
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    • pp.190-199
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    • 2019
  • $Carbopol^{(R)}$ 907 used as surface protecting agent in White's method is the one of the artificial caries lesion producing solution was discontinuing of production. New surface protecting material to substitute of $Carbopol^{(R)}$ 907 was required. The author prepared an artificial caries lesion producing solution as follows White's method with $Carbopol^{(R)}$ 907 and also another artificial caries lesion producing solution with $Carbopol^{(R)}$ $2050^{(R)}$. 96 flattened and polished enamel samples were immersed in a demineralizing solution of 0.1 mol/L lactic acid, 0.2% carboxyvinylpolymer and 50% saturated hydroxyapatite for 1, 2, 3, 4, 5, 6, 7, 9, 11, 15, 18 and 20 days. All samples from each group were subjected to polarized microscopy observed and image analysis for measuring the lesion depth. From the review of polarized images, the artificial caries lesion producing solution using $Carbopol^{(R)}$ 907 and $Carbopol^{(R)}$ 2050 can produced an artificial caries that was very similar to natural caries characters. From the regression analysis of the lesion depth produced by the artificial caries lesion producing solution using $Carbopol^{(R)}$ 907 and $Carbopol^{(R)}$ 2050, $Carbopol^{(R)}$ 2050 estimate as Y = 9.8X + 8.0 and $Carbopol^{(R)}$ 907 was Y = 8.4X - 0.4. R square value of $Carbopol^{(R)}$ 2050 and $Carbopol^{(R)}$ 907 was 0.965 and 0.945 respectively. The rate of demineralization by the artificial caries lesion producing solution using $Carbopol^{(R)}$ 2050 was faster than that of $Carbopol^{(R)}$ 907. And R square value of $Carbopol^{(R)}$ 2050 and $Carbopol^{(R)}$ 907 were very high and it means that the lesion depth was very high coefficient to demineralization period.

Applicability of Artificial Light Source and Newly Developed Growing Medium for Lettuce Cultivation in a Closed-type Plant Production System (밀폐형 식물생산시스템에서 상추재배를 위한 인공광원과 신개발 배지의 적용)

  • Lee, Hye Ri;Kim, Hye Min;Kim, Hyeon Min;Park, Sang Hyun;Hwang, Seung Jae
    • Journal of Bio-Environment Control
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    • v.28 no.2
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    • pp.134-142
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    • 2019
  • This study was conducted to evaluate the growth characteristics of lettuce (Lactuca sativa L.) as affected by artificial light sources and different growing media in a closed-type plant production system (CPPS). The lettuce seeds were sown in the 128-cell plug tray filled with 5 different growing media such as urethane sponge (US), rock-wool (RW), Q-plug (QP), TP-S2 (TP) and PU-7B (PU). The germination rate of lettuce seeds was examined during 12 days after sowing. On the 13 days after sowing, the lettuce seedlings were transplanted in a CPPS with temperature $25{\pm}1^{\circ}C$ and nutrient solution (EC $2.0dS{\cdot}m^{-1}$, pH 6.5) using recirculating deep floating technique system. The light sources were set with FL (fluorescent lamps) and combined RB LEDs (red : blue = 7 : 3) with $150{\pm}10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD and a photoperiod of 14/10 hours (light/dark). The initial germination rate of lettuce was the highest in TP. The final germination and mean daily germination were the significantly highest in RW, QP and TP. The plant height, leaf length, leaf width, leaf area, and fresh and dry weights of shoot were the greatest in QP irradiated with RB LED. The number of leaves, fresh and dry weights of root and SPAD were the greatest in QP and TP irradiated with RB LED. The root length was the longest in TP irradiated with RB LED. Therefore, these results indicate that RB LED was effective for the growth of lettuce and it was also found that the QP and TP were effective for the germination and growth of lettuce in a CPPS. In addition, we confirmed the applicability of the newly developed growing medium TP for the lettuce production in a CPPS.

Effects of Wind Net Shading and Sprinkling on Growing Conditions and Fruit Quality in 'Hongro' and 'Fuji' Apple Fruits (방풍망 차광시설 및 미세살수 처리가 '홍로' 및 '후지' 사과나무의 생육환경 및 과실 품질에 미치는 영향)

  • Kang, Kyeong-Jin;Seo, Jeong-Hak;Yoon, Hong-Ki;Seo, Jeong-Seok;Choi, Taek-Yong;Chun, Jong-Pil
    • Journal of Bio-Environment Control
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    • v.28 no.2
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    • pp.126-133
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    • 2019
  • In recent years, the deterioration of fruit quality caused by poor coloration and sunburn disorder has become serious problems in apple market, which is a result of the increase of surface temperature due to the abnormal temperature increase during summer season. This study was conducted to investigate the effect of wind net shading and fine water spray using sprinkler on fruit coloration, sunburn damage and overall fruit quality of 'Fuji' and 'Hongro' apples. Fifteen sprinklers (7L/hr) were installed at the orchard of the Chungcheongnam-do Agricultural Research and Extension Services, located in Sinam-myeon Chungcheongnam-do Korea, at a height of 3m above the apple tree of $1.5m{\times}3.5m$ north-south direction. Fine water spraying treatment was divided into day time spray (10:00 am to 6:00 pm) and all day spray (10:00 am to 10:00 pm) from early July to 10 days before harvest in 2017 and 2018 season, respectively. Temperature of the surface of apple fruit, characteristic of fruit, and degree of sunburn damage were investigated. In 'Fuji', the fruit surface temperature checked at 2 pm on August 10 was decreased considerably in the day time spray ($35.6^{\circ}C$) and wind net ($39.0^{\circ}C$) when compared with the untreated control ($44.4^{\circ}C$). Similarly, the fruit surface temperature also decreased considerably in the all day spray ($35.1^{\circ}C$) and wind net ($36.9^{\circ}C$) treatments when compared with the untreated control ($46.5^{\circ}C$) in 'Hongro' apples. The incidence of sunburn disorder was significantly decreased with day time spray (5.0%), all day spray (5.8%) and wind net (7.0%) when compared with untreated control (23.4%) in 'Fuji' apples. As a results, the treatment of fine water spray and wind net consequently showed 26% and 34% increase of redness ($a^*$) value in the skin color difference, respectively, in 'Fuji' apples.

Graft-taking and Growth Characteristics of Grafted Cucumber(Cucumis sativus L.) Seedlings as Affected by Light Quality and Blink Cycle of LED Modules (LED 모듈의 광질 및 점멸주기에 따른 오이접목묘의 활착 및 생장 특성)

  • Kim, Hyeong Gon;Choi, Yu Hwa;Kim, Yong Hyeon
    • Journal of Bio-Environment Control
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    • v.28 no.2
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    • pp.143-149
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    • 2019
  • This study was conducted to investigate the graft-taking and growth of grafted cucumber seedlings as affected by light quality and blink cycle of LED modules. Four light quality treatments, namely blue, red, blue+red, white LED and four blink cycle levels of 5s/5s, 7s/3s, 9s/1s and control were provided to investigate the effect of lighting quality and blink cycle on the graft-taking and growth of grafted cucumber seedlings. Photoperiod for the control was 12/12 h. Photosynthetic photon flux, air temperature, and relative humidity for healing were maintained at $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, $25^{\circ}C$, and 90%, respectively. There was no significant difference in graft-taking of grafted cucumber seedlings according to light quality except the blue LED with the blink cycle of 5s/5s. Regardless of the blink cycle, there was no significant difference in graft-taking of cucumber seedlings healed under red, blue+red, and white LED modules. These results implied that the effects of light quality and blink cycle on the graft-taking were not significant. Differences in the leaf length, leaf area, and fresh weight of cucumber seedlings healed blue or red LED with the blink cycle of 9s/1s were found to be significant. There was no significant effect of the blink cycle on the growth of cucumber seedlings healed under white LED modules. The prices of white LED are gradually falling due to increased demand. Considering the manufacturing unit price of white LED modules, the cost savings of 10-15% are expected as compared to the conventional blue/red LED modules. Therefore, it was concluded that the use of white LED modules will be economical as an artificial lighting sources for healing of grafted seedlings.

Effect of Semisulcospira libertina Extracts from Different Extraction Processes on Liver Cell Toxicity and Ethanol Metabolism (간세포 독성과 에탄올 대사에서 추출 조건에 따른 다슬기 추출물의 효과)

  • Cho, Kyoung Hwan;Choo, Ho Jin;Seo, Min Gyun;Kim, Jong Cheol;Shin, Yu Jin;Ryu, Gi Hyung;Cho, Hee Young;Jeong, Chi-Young;Hah, Young-Sool
    • Food Engineering Progress
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    • v.21 no.2
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    • pp.158-166
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    • 2017
  • Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were $77.0{\pm}4.3%$ and $81.5{\pm}1.3%$ at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group ($67.8{\pm}4.3%$) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.

Identification and Chromosomal Reshuffling Patterns of Soybean Cultivars Bred in Gangwon-do using 202 InDel Markers Specific to Variation Blocks (변이영역 특이 202개 InDel 마커를 이용한 강원도 육성 콩 품종의 판별 및 염색체 재조합 양상 구명)

  • Sohn, Hwang-Bae;Song, Yun-Ho;Kim, Su-Jeong;Hong, Su-Young;Kim, Ki-Deog;Koo, Bon-Cheol;Kim, Yul-Ho
    • Korean Journal of Breeding Science
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    • v.50 no.4
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    • pp.396-405
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    • 2018
  • The areas of soybean (Glycine max (L.) Merrill) cultivation in Gangwon-do have increased due to the growing demand for well-being foods. The soybean barcode system is a useful tool for cultivar identification and diversity analysis, which could be used in the seed production system for soybean cultivars. We genotyped cultivars using 202 insertion and deletion (InDel) markers specific to dense variation blocks (dVBs), and examined their ability to identify cultivars and analyze diversity by comparison to the database in the soybean barcode system. The genetic homology of "Cheonga," "Gichan," "Daewang," "Haesal," and "Gangil" to the 147 accessions was lower than 81.2%, demonstrating that these barcodes have potentiality in cultivar identification. Diversity analysis of one hundred and fifty-three soybean cultivars revealed four subgroups and one admixture (major allele frequency <0.6). Among the accessions, "Heugcheong," "Hoban," and "Cheonga" were included in subgroup 1 and "Gichan," "Daewang," "Haesal," and "Gangil" in the admixture. The genetic regions of subgroups 3 and 4 in the admixture were reshuffled for early maturity and environmental tolerance, respectively, suggesting that soybean accessions with new dVB types should be developed to improve the value of soybean products to the end user. These results indicated that the two-dimensional barcodes of soybean cultivars enable not only genetic identification, but also management of genetic resources through diversity analysis.