• 센서학회지
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• 제1권2호
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• pp.173-181
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• 1992

RP 반응성 스펏터링으로서 P형 실리콘 웨이퍼위에 $Ta_{2}O_{5}$막을 제조하였다. 시편의 구조 및 조성은 XRD와 AES로 조사하였다. 산소의 혼합비가 10%일 때 C-V 특성으로부터 구한 $Ta_{2}O_{5}$막의 비유전률은 10-12이었다. AES와 RBS로 측정한 $Ta_{2}O_{5}$막의 Ta : O의 비는 각각 1 : 2와 1 : 2.49로 나타났으며, 산소분위기에서 $700^{\circ}C$의 열처리 온도에서 결정성장이 시작되었다. 산소분위기에서 $1000^{\circ}C$로 열처리한 $Ta_{2}O_{5}$막의 비유전률값은 20.5였으며, 질소분위기에서 열처리한 경우의 비유전률값은 23으로 나타났다. 이 때 가육방전계(pseudo hexagonal ${\delta}-Ta_{2}O_{5}$)의 결정구조를 나타내었다. 시편의 ${\Delta}V_{FB}$와 누설전류밀도는 산소의 혼합비가 증가함에 따라 감소하였다. 그리고 최대절연파괴전장은 산소가 10% 혼합되었을 때 2.4MV/cm로 나타났다. 이러한 $Ta_{2}O_{5}$막은 수소이온 감지막 및 기억용소자의 게이트 절연막 등에 응용될 수 있을 것이다.

• Biomolecules & Therapeutics
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• 제28권4호
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• pp.354-360
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• 2020

The hair cycle (anagen, catagen, and telogen) is regulated by the interaction between mesenchymal cells and epithelial cells in the hair follicles. The proliferation of dermal papilla cells (DPCs), mesenchymal-derived fibroblasts, has emerged as a target for the regulation of the hair cycle. Here, we show that vanillic acid, a phenolic acid from wheat bran, promotes the proliferation of DPCs via a PI3K/Akt/Wnt/β-catenin dependent mechanism. Vanillic acid promoted the proliferation of DPCs, accompanied by increased levels of cell-cycle proteins cyclin D1, CDK6, and Cdc2 p34. Vanillic acid also increased the levels of phospho(ser473)-Akt, phospho(ser780)-pRB, and phospho(thr37/46)-4EBP1 in a time-dependent manner. Wortmannin, an inhibitor of the PI3K/Akt pathway, attenuated the vanillic acid-mediated proliferation of DPCs. Vanillic acid-induced progression of the cell-cycle was also suppressed by wortmannin. Moreover, vanillic acid increased the levels of Wnt/β-catenin proteins, such as phospho(ser9)-glycogen synthase kinase-3β, phospho(ser552)-β-catenin, and phospho(ser675)-β-catenin. We found that vanillic acid increased the levels of cyclin D1 and Cox-2, which are target genes of β-catenin, and these changes were inhibited by wortmannin. To investigate whether vanillic acid affects the downregulation of β-catenin by dihydrotestosterone (DHT), implicated in the development of androgenetic alopecia, DPCs were stimulated with DHT in the presence and absence of vanillic acid for 24 h. Western blotting and confocal microscopy analyses showed that the decreased level of β-catenin after the incubation with DHT was reversed by vanillic acid. These results suggest that vanillic acid could stimulate anagen and alleviate hair loss by activating the PI3K/Akt and Wnt/β-catenin pathways in DPCs.

• 대한수의학회지
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• 제36권3호
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• pp.551-563
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• 1996

This study investigated the properties of primary cultured proximal tubule cells in hormonally defined(insulin, transferrin, and hydrocortisone), serum-free medium or 10% serum-supplemented medium. The growth rate of the primary cultured proximal tubule cells was lower in the hormonally defined, serum-free medium than in the 10% serum- supplemented medium(p < 0.05), while the activities of brush border marker enzymes, alkaline phosphatase(AP), leucine aminopeptidase(LAP), and y-glutamyl transpeptidase(${\gamma}$-GTP) were increased(p < 0.05). The activities of these enzymes, however, decreased with the lapse of incubation time to 50-70% after 6 days culture compared to those of the freshly-prepared proximal tubules. The enzymatic activities of the primary cultured proximal tubul cells on 6, 9, 12, and 15 days of culture were significantly increased in the hormonally defined, serum-free medium compared to the 10% serum-supplemented medium(p < 0.05). The functional differentiation of the primary culture was examined by observing multicellular domes of the confluent monolayer, which is indicative of transepithelial solute transport. The dome formation by the proximal tubule cultures occurred at a higher frequency in the hormonally defined, serum-free medium than in the 10% serum-supplemented medium(p < 0.05). Upon electron microscopic examination, an increased density of the brush border was observed in the hormonally defined, serum-free medium compared to the cells grown in 10% serum-supplemented medium. The activities of $Na^+$glucose cotransporter($^{14}C$-a-MG uptake), $Na^+$phosphate cotransportere($^{32}P$ uptake) and $Na^+$ transporter($^{22}Na^+$ uptake) in the brush border membrane, and of $Na^+/K^+$-ATPase($^{86}Rb$ uptake) in the basolateral membrane were significantly stimulated in the hormonally defined, serum-free medium than in 10% serum-supplemented medium(p < 0.05). In conclusion, the primary cultured proximal tubule cells grown in the hormonally defined, serum-free medium demonstrated a slower growth rate, but the functions of cell were enhanced.

• 한국어병학회지
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• 제7권1호
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• pp.13-22
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• 1994

우리나라에 존재하며 외국에서 분리된 것과 다른 특성을 보이는 IHNV를 대상으로 하여 이 바이러스의 면역유도단백질을 확인하고자 하였다. 먼저 우리나라에서 분리된 4종류의 IHNV를 미국에서 분리된 3종류의 IHNV(OSV, SRCV 및 RB-76)와 SDS-PAGE상에서 구조단백질의 크기와 혈청학적 특성 등을 비교하였다. 그 결과 우리나라에서 분리된 4종류의 IHNV중 2종류(PRT, MRT)의 IHNV는 미국에서 분리된 IHNV와 차이가 있었으며 (Park et al., 1993), IHNV-PRT를 대상으로 면역유도단백질을 확인하기 위해 IHNV-PRT에 대한 monoclonal antibodies(MAbs)를 만들었다. 이들 중 4종류의 hybridoma를 선택하여 hybridoma cell들이 분비하는 MAbs가 어떤 class인지를 ELISA 실험을 통하여 확인한 결과 4종류 모두 IgG class에 속하는 것으로 확인되었다. 이와같이 만들어진 4종류의 MAbs가 IHNV-PRT 구조단백질들 중 어떤 것에 대한 것인지를 western blotting 실험을 통해 확인한 결과, 2종류의 MAbs는 G단백질과 특이성이 있는 것들이었고, 나머지 2종류는 G보다 조금 큰 size의 단백질에 대한 것들이었다. 다음은 IHNV-PRT에 감염된 무지개송어의 혈청을 뽑아 여기에 존재하는 IHNV-PRT에 대한 항체를 western blotting 방법으로 분석을 한 결과 G, $M_1$, $M_2$ 및 G 보다 조금 큰 size의 단백질에 대한 항체가 존재하는 것으로 나타났다. 이상의 결과로부터 IHNV-PRT의 구조단백질들 중 G, $M_1$, $M_2$ 및 G 보다 조금 큰 size의 단백질들이 면역 유도 특성이 있음을 확인할 수 있었다.

• 한국약용작물학회지
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• 제6권4호
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• pp.305-310
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• 1998

인삼(人蔘)을 열수추출방법(熱水抽出方法)으로 추출(抽出), 농축(濃縮)하여 엑스를 제조(製造)할때 인삼(人體)에 무해(無害)한 탄산수소(炭酸水素)나트륨, 탄산(崙酸)나트륨 등(等)의 약염기(弱鹽基)를 수삼(水蔘)과 백삼내(白蔘內) 유기산(有機酸) 당량비(當量比)로 첨가한(添加) 결과(結果), 유기산(有機酸) (함량(含量) : citric acid 4.12, 13.05 mg/g, malonic acid 0.68, 2. 18 mg/g, succinic acid 0.13, 0.46 mg/g, malic acid 2.68, 8.62 mg/g)을 중화하여 주된 유효성분(有效成分)인 사포단의 분해(분해) 없이 추출(抽出)할 수 있었으며, 갈색화 반응(反應)을촉진(促進)하여 추출물(抽出物)의 갈색도(褐色度)를 높일 수 있었다. 이와 같은 가수분해(加水分解) 현황(現況)은 $C_{20}$ 위치(位置)의 가수분해(加水分解)가 주(主)된 요인(要因)이었으며, protopanaxadiol과 protopanaxatriol의 $C_3$와 $C_6$에 결합(結合)된 glucoside 결합(結合)은 전자밀도(電子密度) 계산결과(計算結果) 전기음성도(電氣陰性度)가 -0.223으로 낮은 2차(次) 탄소(炭素)에 결합(結合)되어 대채로 안정(安定)하였으나 $C_{20}$ 위치(位置)의 glucosidp 결합(結合)은 전기음성도(電氣陰性度)가 -0.295로 높은 제(第) 3차(次) 탄소(炭素)에 결합(結合)되어 약산용액(弱酸溶液) 가열조건(加熱條件)에서 산가수분해(酸加水凉解)가 용역(容易)하였으며, 사포닌의 3번(番), 6번(番곯)과 20번(番) 탄소(炭素)의 산(酸)과 효소(酵素)에 의한 가수분해(加水分解)와 차이는 전기음성도(電氣陰性度)와 입체장애(立體障碍)에 의한 차이(差異)에 의한 것으로 생각되었다.

• 한국약용작물학회지
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• 제24권5호
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• pp.375-385
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• 2016

Background: The study was conducted to elucidate the extraction conditions under which white ginseng has cognition-improving efficacy. Methods and Results: Extracts from white ginseng under different solvent and temperature conditions were analyzed for ginsenoside content and inhibitory effect on N-methyl-D-aspartate (NMDA) receptor and acetylcholinesterase. The total ginsenoside contents and amounts of ginsenoside Rb1 plus ginsenoside Rg1 from the 1st extracts (prepared with EtOH/$H_2O$ as solvent) were higher than those from the 2nd extracts (extracted with $H_2O$ after the 1st EtOH/$H_2O$ extraction). The contents in the 1st and 2nd extracts produced at $80^{\circ}C$ were also higher than those obtained at $50^{\circ}C$. Samples from the 1st extraction at $80^{\circ}C$ indicated higher inhibitory activities on NMDA receptors-whose excessive activation is thought to mediate the calcium-dependent neurotoxicity associated with several neurodegenerative diseases-than those from the 2nd extraction. Among the samples prepared at varying temperatures, the extract prepared at $50^{\circ}C$ showed the highest suppression activity on NMDA receptors. Note, however, that the extracts from the 2nd extraction at $50^{\circ}C$ inhibited acetylcholinesterase-whose inhibition could be a therapeutic strategy for neurodegenerative diseases with cognitive deficits and memory malfunction-more effectively than those from the 1st extraction. Conclusions: To enhance the cognition-improving activity of white ginseng extract, it is suggested that the extracts be utilized after being combined the 1st extracts (made with EtOH/$H_2O$ solvent) and the 2nd extracts (prepared with $H_2O$) at low temperature.

• 한국재료학회지
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• 제6권7호
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• pp.733-741
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• 1996

본 연구에서는 MeV Si 자기 이온주업을 실시하여 주업원자와 모재 원자와의 화학적 영향이 배제된 결함 형성 거동을 관찰하였다. 자기 이온주업을 위하여 Tandem Accelerator가 사용되었고 1~3 MeV의 에너지 범위의 이온주입이 실시되었다. MeV 이온주입된 시편의 격자결함은 표면으로부터 고립된 $R_p$ 근처에 집중된 것이 관찰되었다. 주입에너지 변화에 따른 격자결함 생성 거동을 관찰하기 위하여 조사량을 $1{\times}10^{15}/cm^2$으로 고정하고 주입에너지를 1~3 MeV로 증가하였다. RBS 분석 결과 격자결함의 형성층 깊이는 에너지 증가에 따라 증가하였고 표면층에는 에너지 증가시 더욱 좋은 결정성을 유지하였다. 또한 주입에너지가 일정한 경우 조사량 증가시 $R_p$ 부근에 집중된 결함층의 농도는 증가하였으나 표면부근의 결함농도는 임계조사량 이상에서 포화되는 것이 관찰되었다. XTEM 분석 결과는 RBS의 결과와 잘 일치하였다. XTEM 관찰 결과 이온주업 상태의 결함층은 dark band의 형태로 관찰되었고 열처리시 이차결함은 이곳으로부터 생성되었다. 2MeV $Si^+$ 자기 이온주입시 이차결함이 형성되는 임계조사량은 $3{\times}10^{14}{\sim}5{\times}10^{14}/cm^2$ 사이로 관찰되었다. 열처리시 dark band의 하단부의 위치는 변화하지 않고 상단부만이 제거되었다. 실험을 통하여 얻은 결과들은 Monte-Carlo technique을 이용한 TRIM-code를 사용하여 해석하였다. SIMS 분석을 통하여 이차결함은 모재내에 존재하는 oxygen 불순물을 gettering함을 관찰하였다.

• 자원환경지질
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• 제16권3호
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• pp.163-221
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• 1983

Main aspects of this study are to clarify geochronology and petrogenetic processes of the so-called Hongjesa granite, which is a member of various intrusive rocks exposed in the northeastern part of the Ryongnam Massif, one of the Precambrian basements of South Korea. In this study, the Hongjesa grainte is divided into four rock units based on the geologic age, mineralogical and chemical constituents, and texture: the Precambrian Hongjesa granite gneiss (Hongjesa granite Proper) and leucogranite gneiss, the Paleozoic gnessic two mica granite, and the Jurassic muscovite granite. The Hongjesa granite gneiss is identified by its grayish color, slight foliation, and porphyroblastic texture. The leucogranite gneiss is distinct by its light gray color, sand medium to coarse grained texture. The gneissic two mica granite is distinguished from others by its strong foliation, containing gray-colored feldspar phenocrysts with biotite and muscovite in varying amounts. The muscovite granite occurs as a small stock containing feldspar phenocrysts along margin of the stock. These granitic rocks vary widely in composition, reflecting the facts that they partly include highly metamorphosed xenolith and schlierens as relics of magmatic and anatectic processes. In particular, grayish porphyroblasts of microcline perthite is characteristic of the Hongjesa granite gneiss, whereas epidote and garnet occur in both the Hongjesa granite gneiss and leucogranite gneiss. These minerals are considered to be formed by potassic metasomatism and contamination of highly metamorphosed rocks deeply buried under the level of the Hongjesa granite emplacement. The individual synchronous granitic rocks plotted on Harker diagram show mostly similar trends to the Daly's values. The plots of the Hongjesa granite gneiss and gneissic two mica granite concentrate near the end part of the calc-alkalic rock series on the AMF diagrams, whereas those of the leucogranite gneiss and muscovite granite indicate the trend of the Skaergaard pluton. These granitic rocks plotted on a Q-Ab-Or diagram (petrogeny's residua system) fall well outside the trough of the system. This can be attributed to the potassic matasomatism of these rocks. On the ACF diagram, these rocks appear to be dominantly I-type prevailing over S-type. The K-Ar ages, obtained from a total of 7 samples of the leucogranite gneiss, gneissic two mica granite, muscovite granite, porphyritic alkali granite, and rhyolitic rock, in addition to the Rb/Sr ages of the Hongjesa granite gneiss by previous workers, permit the rock units to be arranged in the following chronological order: The middle Proterozoic Hongjesa granite gneiss (1714-1825 m.y.), the upper proterozoic leucogranite gneiss (875-880 m. y.), the middle Paleozoic gneissic two mica granite (384 m. y.) the upper Jurassic muscovite granite (147 m. y.), the Eocene alkali granite (52 m. y.), and the Eocene rhyolitic rock (45 m. y.). From the facts and data mentioned above, it is concluded that the so-called Hongjesa granite is not a single granitic mass but is further subdivided into the four rock units. The Hongjesa granite gneis, leucogranite gneiss, and gneissic two mica granite are postulated to be either magmatic or parautochtonous, intrusive, and the later muscovite granite is to be magmatic in origion.

• 한국대기환경학회지
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• 제22권5호
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• pp.590-603
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• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

• 자원환경지질
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• 제26권4호
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• pp.489-498
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• 1993

경북 봉화군 소천면 소재 옥방 회중석광산 주변부에 분포하는 앰피볼라이트는 그 암석성인적 측면에서 많은 관심을 불러 일으켰다. 이 앰피볼라이트는 선캠브리아기의 원남층군내에 관입암상의 형태로 산출되며 옥방회중석광산의 모암이기도 하다. 주성분과 미량성분의 지구화학적 특징에 의하면, 이 앰피볼라이트는 정앰피볼라이트로서 비알카리 계열의 쏘레라이트 현무암질 암석으로 분류되며 쏘레라이트의 분화경향을 그대로 따르고 있었다. 희토류원소 및 친액상원소들의 지구화학적 특징에 의하면, 이 앰피볼라이트를 형성한 기원암의 마그마는 친액상원소들이 결핍된 상부맨틀로부터 유래되었으며 상승도중 대륙지각물질의 혼염이 있었고 이 마그마가 관입된 조구조적 환경이 대륙배호분지 (continental back-arc basin)임을 강력하게 시사하고 있다. 따라서 이 앰피볼라이트에 의해 관입된 원남층군이 퇴적된 조구조 환경 역시 대륙배호분지에 해당됨을 암시한다고 할 수 있다.