• Title/Summary/Keyword: 중국과학원

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Composition and pollution characteristics of TSP, PM2.5 atmospheric aerosols at Gosan site, Jeju Island (제주도 고산지역 TSP, PM2.5 대기에어로졸의 조성 및 오염 특성)

  • Lee, Soon-Bong;Kang, Chang-Hee;Jung, Duk-Sang;Ko, Hee-Jung;Kim, Haeng-Bum;Oh, Yong-Soo;Kang, Hae-Lim
    • Analytical Science and Technology
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    • v.23 no.4
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    • pp.371-382
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    • 2010
  • TSP and PM2.5 atmospheric aerosols have been collected at Gosan site of Jeju Island, and their compositions were analyzed to understand the pollution characteristics. The composition ratios of nss (non-sea salt)-$SO_4^{2-}$ and $NH_4^+$ were higher in Gosan site than those in other Korean background and urban sites. However the composition ratio of $NO_3^-$ was conversely lower in Gosan site. From the study of aerosol components according to particle sizes, the anthropogenic nss-$SO_4^{2-}$, $NO_3^-$ and $NH_4^+$ components were mostly existed in the fine particles. But the nss-$Ca^{2+}$, $Na^+$, $Cl^-$ and $Mg^{2+}$ originated from soil and marine sources were distributed relatively in the coarse particles. In the seasonal comparison, the concentrations of nss-$Ca^{2+}$, Al, Fe, Ca and $NO_3^-$ increased in spring season, and nss-$SO_4^{2-}$ showed higher concentration in summer and spring seasons. Based on the factor analysis, the atmospheric aerosols in Gosan site have been found to be influenced largely by anthropogenic sources, and next by marine and soil sources. The backward trajectory analyses showed that the concentrations of nss-$SO_4^{2-}$, $NO_3^-$, Pb and nss-$Ca^{2+}$ increased when the air mass moved from Chinese continent to Jeju area. On the other hand, their concentrations decreased when the air mass moved in from the North Pacific Ocean.

Single Dose Oral Toxicity Test of Ethanol Extracts of Schisandrae fructus and Mori folium, and their Mixture in ICR Mice (ICR 마우스를 이용한 오미자, 상엽 에탄올 단독추출물 및 복합추출물의 단회경구투여 독성시험)

  • Choi, Eun Ok;Kwon, Da Hye;Kim, Min Young;Hwang-Bo, Hyun;Kim, Hong Jae;Ahn, Kyu Im;Jeong, Jin-Woo;Lee, Ki Won;Kim, Ki Young;Kim, Sung Goo;Choi, Young Whan;Hong, Su Hyun;Park, Cheol;Choi, Yung Hyun
    • Journal of Life Science
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    • v.26 no.10
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    • pp.1207-1213
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    • 2016
  • Schisandrae fructus (SF) and Mori folium (MF) have been used as traditional medicines for thousands of years in parts of Asia, including Korea, China, and Japan. Recent researches on SF and MF have documented a wide spectrum of therapeutic properties, including anti-microbial, anti-inflammatory, anti-oxidative, immunomodulatory and anti-angiogenesis effects. However, the toxicity and safety of SF and MF, and their mixture (medicinal herber mixture, MHMIX) were not confirmed. Therefore, this study was performed to evaluate the acute toxicity and safety of SF, MF and MHMIX. SF, MF and MHMIX were orally administered at a dose of 5,000 mg/kg in ICR mice. Animals were monitored for the mortality and changes in the body weight, clinical signs and gross observation during the 14 days after dosing, upon necropsy. We also measured parameters of organ weight, clinical chemistry, and hematology. No dead and no clinical signs were found during the experiment period after administration of a single oral dose of SF, MF and MHMIX. There were no adverse effects on clinical signs, body weight, or organ weight and no gross pathological findings in any treatment group. Therefore, LD50 value of SF, MF and MHMIX may be over 5,000 mg/kg and it may have no side toxic effect to ICR mice. The results on the single-dose toxicity of SF, MF and MHMIX indicate that it is not possible to reach oral dose levels related to death or dose levels with any harmful side effects.

Regeneration Processes of Nutrients in the Polar Front Area of the East Sea III. Distribution Patterns of Water Masses and Nutrients in the Middle-Northern last Sea of Korea in October, 1995 (동해 극전선역의 영양염류 순환 과정 III. 1995년 10월 동해 중부 및 북부 해역의 수괴와 영양염의 분포)

  • CHO Hyun-Jin;MOON Chang-Ho;YANG Han-Seob;KANG Won-Bae;LEE Kwang-Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.3
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    • pp.393-407
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    • 1997
  • A survey of biological and chemical characteristics in the middle-northern East Sea of Korea was carried out at 28 stations in October, 1995 on board R/V Tam-Yang. On the basis of the vertical profiles of temperature, salinity and dissolved oxygen, water masses in the study area were divided into 5 major groups; (1) Low Saline Surface Water (LSSW), (2) Tsushima Surface Water (TSW), (3) Tsushima Middle Water (TMW), (4) North Korean Cold Water (NKCW), (5) last Sea Porper Water (ESPW). Other 4 mixed water masses were also observed. It is highly possible that the LSSW which occured at depths of $0\~30m$ in the most southern part of the study area is originated from the Yangtze River (Kiang) of China due to very low salinity $(<32.0\%_{\circ})$ relatively high concentration of dissolved silicate and no sources of freshwater input into that area. Oxygen maximum layer in the vertical profile was located near surface at northern cold waters and became deeper at the warm southern area. Oxygen minimum layer af depths $50\~100m$, which is TMW, were found in only southern area. In the vortical profiles of nutrients, the concentrations were very low in the surface layer and increased drammatically near the thermocline. The highest concentration occurred in the ESPW. The relatively low value of Si/P ratio in the ESPW (13.63) compared to other reports in the East Sea was due to continuous increase of P with depth as well as Si. The N : P ratio was about 6.92, showing that nitrogenous nutrient is the limiting factor for phytoplankton growth. The exponential relationship between Si and P, compared to the linear relationship between N and P, indicates that nitrate and phosphate have approximately the same regenerative pattern, but silicate has delayed regenerative pattern.

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Calculation Method of Oil Slick Area on Sea Surface Using High-resolution Satellite Imagery: M/V Symphony Oil Spill Accident (고해상도 광학위성을 이용한 해상 유출유 면적 산출: 심포니호 기름유출 사고 사례)

  • Kim, Tae-Ho;Shin, Hye-Kyeong;Jang, So Yeong;Ryu, Joung-Mi;Kim, Pyeongjoong;Yang, Chan-Su
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1773-1784
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    • 2021
  • In order to minimize damage to oil spill accidents in the ocean, it is essential to collect a spilled area as soon as possible. Thus satellite-based remote sensing is a powerful source to detect oil spills in the ocean. With the recent rapid increase in the number of available satellites, it has become possible to generate a status report of marine oil spills soon after the accident. In this study, the oil spill area was calculated using various satellite images for the Symphony oil spill accident that occurred off the coast of Qingdao Port, China, on April 27, 2021. In particular, improving the accuracy of oil spill area determination was applied using high-resolution commercial satellite images with a spatial resolution of 2m. Sentinel-1, Sentinel-2, LANDSAT-8, GEO-KOMPSAT-2B (GOCI-II) and Skysat satellite images were collected from April 27 to May 13, but five images were available considering the weather conditions. The spilled oil had spread northeastward, bound for coastal region of China. This trend was confirmed in the Skysat image and also similar to the movement prediction of oil particles from the accident location. From this result, the look-alike patch observed in the north area from the Sentinel-1A (2021.05.01) image was discriminated as a false alarm. Through the survey period, the spilled oil area tends to increase linearly after the accident. This study showed that high-resolution optical satellites can be used to calculate more accurately the distribution area of spilled oil and contribute to establishing efficient response strategies for oil spill accidents.

Inhibitory Effect of Protaetia brevitarsis seulensis Ethanol Extract on Neuroinflammation in LPS-stimulated BV-2 Microglia (LPS에 의해 활성화된 미세아교세포에서 흰점박이꽃무지 에탄올 추출물의 신경염증 억제 효과)

  • Lee, Hwa Jeong;Seo, Minchul;Lee, Joon Ha;Kim, In-Woo;Kim, Sun Young;Hwang, Jae-Sam;Kim, Mi-Ae
    • Journal of Life Science
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    • v.29 no.10
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    • pp.1096-1103
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    • 2019
  • Neuroinflammation is mediated by the activation of microglia and has been implicated in the pathogenesis of neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease. Therefore, the inhibition of neuroinflammation may be an effective solution to treat these brain disorders. Protaetia brevitarsis seulensis is an insect belonging to the order Coleoptera and inhabits Korea, China, Japan and Siberia. P. brevitarsis seulensis is an edible insect that can be consumed as a protein source for humans. It has been reported that P. brevitarsis seulensis contains useful bioactive substances for hepatoprotection and improving blood circulation, such as indole alkaloids. Microglia cells are the main source of proinflammatory cytokines and nitric oxide (NO) in the central nervous system, which Perform neuroimmune, inflammatory, and other neurobilogical functions. In this study, we investigated the anti-neuroinflammatory effects of P. brevitarsis seulensis ethanol extract (PBE) in activated microglia cells treated with lipopolysaccgarude (LPS, 100 ng/ml). As a result, PBE significantly inhibited NO production without cytotoxicity and decreased the expression levels of inducible NO synthase and cyclooxygenase-2. In addition, the production of inflammatory cytokine secreted by LPS was also reduced by PBE. These results suggest that PBE could be a good source of functional substances to prevent neuroinflammation and neurodegenerative diseases.

A Review on Treasure No.1167, Unified Silla Buddhist Bell from Uncheon-dong, Cheongju, about Its Form and Conservational Scientific Features (보물 제1167호 청주 운천동 출토 통일신라 범종의 형태와 보존과학적 특성 고찰)

  • Kim, Hyun-jeong;Kim, Su-gi
    • Korean Journal of Heritage: History & Science
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    • v.40
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    • pp.357-386
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    • 2007
  • At present, thirteen Buddhist bells of Unified Silla are known to the world: Six in Korea, five in Japan and two other bells, and three out of them are impossible to make out its original form. Therefore, we divided the form of Unified Silla Buddhist bells based on the ten other bells, and we tried out to prove the manufacturing technology by the comparison of the research material of Uncheon-dong bell and existing research materials of other bells, in other to find their linkage based on the alloy elemental composition. We divided Unified Silla Buddhist bell into two types: Type I has symmetric apsaras and regular patterns on its face and it was made in early Silla period; type II has asymmetric apsaras and irregular pattern arrangement and made in late Silla period. In particular, Uncheon-dong Buddhist bells is very similar to Komyoji[光明寺] temple bell from ninth century in Japan. It is peculiar that the apsaras on Uncheon-dong bell play vertical music instruments that are never seen in Unified Silla Buddhist bell. Most of Unified Silla Buddhist bell are compounded with Cu-Sn or Cu-Sn-Pb system. From eighth and ninth century, bells were cast with even composition of copper, tin and lead, and the bronze alloy ratio was similar to the record in Gogonggi[考工記], Jurye[周禮], a book from ancient China. Particularly, Uncheon-dong bell is in a rare case of Cu-Sn-Pb-As system. As had been rarely used in Unified Silla Buddhist bells, so we presented the relative research materials. As has the same nature as Pb. Because As easily volatilize at high temperature, it is hard to use. But it has its merit of solidity and durability. Pb enhances fluidity and thereby expresses the patterns more distinct; As makes the bell stronger. The result of lead isotope ratio could not exactly reveal a concrete producing center. However, over the analysis of our samples, hereby we suggest Uncheon-dong bell was made of materials from just one ore deposit.

A study on the essence of Ye and its usualness - With focus on Shirak's feature of Yulkok's Yegyo (예(禮)의 본질(本質)과 일상성(日常性) - 율곡(栗谷) 예교(禮敎)의 실학적(實學的) 성격(性格)과 일상성(日常性)을 중심으로 -)

  • Lee, Haeng-hoon
    • (The)Study of the Eastern Classic
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    • no.35
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    • pp.161-188
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    • 2009
  • Confucianism's concept of Ye is ruled by the absolute principle of the universe on one hand, and by "the rules of Ye(節文)" and "the rules of ceremony(儀則)", the principle of relative articulation on the other hand. The realizations of the absolute principle of Ye is depending on its usage in everyday life which is fundamentally conditioned by time and space. Thus, Ye's usage can be maximized when the fundamental principle and the condition of its usage make a mutual harmony. Of course, Ye and Ak(樂) are doing complementary roles for each other, since Ye is a principle of a division and Ak is a principle of combining features. However, the essence of Ye can be figured out as the characteristics of mutual reciprocity among things of hierarchy between the classes. Not only in Modern one But also in the medieval society, Ye was not a one-sided force. The essence of Ye does not retain the interests of an individual and the power of a group. If so, the formal aspects of Ye had been distorted. Confucianism demands a strict morality and ethics of a normal person as well as of the ruler. The characteristics of Ye is democratic and open to the condition of time and space. Yegyo should be rooted in everyday lives and realized as a usualness. Therefore, Shirak was an inevitable feature of Yegyo. During the 16th and the 17th century, Ye insinuated into everyday lives of the public in the Korean society. Yulgok Yiyi(李珥)'s Haejuhyangyak(海州鄕約) was estimated as the exemplary feature of Shirak.

A Comparison of Dietary Behaviors According to Gender and Obesity Status of Middle School Students in Jeonju (전주지역 중학생의 성별 및 비만판정에 따른 식행동 비교 연구)

  • Sung, Sun-Hwa;Yu, Ok-Kyeong;Son, Hee-Sook;Cha, Youn-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.8
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    • pp.995-1009
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    • 2007
  • The purpose of this study was to investigate the dietary habits, behaviors, and food consumption frequency according to gender and obesity level among middle school students in the Jeonju area. Subjects for the questionnaire were 450 middle school students (male 255, female 195) and were classified as either obese students (n=150 or non-obese students (n=299) by the obesity assessment method. The results were analyzed with SAS program (Version 9.1), and were as follows. 1. Dietary behaviors were significantly different in the rate of 'Skipping breakfast (p<0.05)', 'Duration of meal time (min) (p<0.05)' and 'Unbalanced diet (p<0.01)' between males and females. Dietary habits and behaviors also differed significantly for the rate of ‘Taste preferences (p<0.05)’, and 'Unbalanced diet (p<0.01)' between obese students and non-obese students. 2. Food consumption frequency per week was as follows. First, males were significantly higher than females in 'Instant noodle (p<0.05)', 'Milk (p<0.01)', and 'Soda pop (p<0.01)'; on the other hand females were significantly higher than males in 'Chocolate, Candy (p<0.01)'. Second, non-obese students were significantly higher than obese students in 'Instant noodle (p<0.05)', 'Hamburger, Pizza (p<0.05)', and 'Chocolate, Candy (p<001)'. Especially, non-obese male students were higher in 'Instant noodle (p<0.05)' and 'Hamburger, Pizza (p<0.05)'; non-obese female students were higher in 'Chocolate, Candy (p<0.01)'. In conclusion, an action program is needed to encourage healthful dietary behaviors, increased physical activity, and forming good lifelong habits.