• 농약과학회지
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• 제11권2호
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• pp.59-66
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• 2007

감수성(SBC) 및 저항성(RBC) 잿빛곰팡이병균(Botrytis cinerea)에 대한 N-phenyl-O-phenylthionocarbamate 유도체들의 살균활성에 대한 3차원적인 구조와 활성과의 관계(3D-QSAR)를 CoMFA와 CoMSIA 방법으로 검토하였다. 최적화 된 CoMFA 모델의 예측성과 상관성이 CoMSIA 모델보다 양호하였으며 ($r^2$ 및 $q^2=CoMFA{\gg}CoMSIA$) SBC 균주에 대한 살균활성 모델이 RBC에 대한 모델보다 양호한 통계값 ($r^2=SBC{\gg}RBC$)을 나타내었다. 또한, CoMFA 모델에서는 정전기장보다 입체장이 큰 영향을 미쳤다. CoMSIA 모델에서는 RBC 및 SBC에 대한 살균활성에 관한 CoMSIA장의 영향은 서로 상이하였으나 수소결합 주게장의 영향은 같았다. 통계적으로 양호한 CoMFA 모델에 의하여 두 균주사이 살균활성에 관한 선택성 요소는 입체장의 차이에 기인하는 것으로 판단된다. 그러므로 N-phenyl 고리상 meta 및 para-치환체의 큰 입체장은 SBC에 대한 살균활성을 향상시킬 것으로 예측되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.133-144
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• 2009

Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

• 대한화학회지
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• 제55권4호
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• pp.612-619
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• 2011

1,2-diphenyl-4-butyl-3,5-pyrazolidinedione(phenylbutazone, PB)의 란탄(III) 착물을 합성하여 원소분석, 몰전기전도도 측정, IR, UV-Vis. 및 NMR 스펙트럼으로 특성을 조사하였다. 스펙트럼 데이터로부터 PB가 pyrazolidinedione 고리의 두 카르보닐 산소를 통해 이배위 및 일이온화 리간드로 배위됨을 규명하였다. 몰전기전도도 데이터로부터 이들 착물이 비전해질임을 규명하였다. 이들 착물의 열적 행동을 공기 중에서 TG 및 DTG로 연구한 결과, 탈수화, 열적 안전성 및 열분해에 관한 정보를 얻을 수 있었다. 최종 생성물은 해당 금속의 산화물로 밝혀졌다. 탈수화 및 분해 단계에 대한 열역학 및 반응속도 파라메터를 구하였다. 분해 단계에 대한 음의 엔트로피 값은 반응물보다 활성화 착물이 더 질서있는 구조를 갖는다는 것을 의미하며, 이때 반응은 정상보다 느렸다. 이러한 연구를 바탕으로 착물의 분자식이 $[Ln(PB)_3]{\cdot}5H_2O$(Ln=La 및 Ce) 그리고 $[Ln(PB)_3 (H_2O)_2]{\cdot}2H_2O$(Ln=Pr, Nd 및 Sm)임을 규명하였다.

• 대한화학회지
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• 제19권2호
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• pp.92-97
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• 1975

$TiCl(OC_6H_5)_3{\cdot}C_6H_5OH\;및\;Ti(OC_6H_5)_4{\cdot}C_6H_5OH$의 분자량 측정과 전자 흡수스펙트럼을 고찰함으로써 이들 두 유기-리탄 화합물들의 용액 상태에서의 분자 및 전자구조에 대하여 연구하였다. $Ti(OC_6H_5)_4{\cdot}C_6H_5OH$는 고체상태에서는 이합체로 존재하지만 분자량 측정 결과 묽은 용액에서는 단위체로 완전해리되며 $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH$도 8mM농도에서 해리를 시작함을 알수 있었다. 따라서 이들 두 착화합물은 묽은 용액에서 5배위 착화합물로 존재하며 분자구조는 trigonalbipyramid으로 생각된다. 두 화합물의 전자 흡수스펙트럼은 자외부쪽에 똑같은 진동구조를 갖는 벤젠고리 특유의 흡수밴드를 나타내며 가시부에서는 $TiCl(OC_6H_5)_3{\cdot}C_6H_5OH$의 경우 26.8kK에 $Ti(OC_6H_5)_4{\cdot}C_6H_5OH$는 29.6kK에 각각 흡수 밴드를 나타낸다. 이가시부 흡수밴드는 리간드에서 금속쪽으로 전하이전에 의한 $^1A_1''{\to}^1E'\;or\;^1E''$ 전이로 생각된다.

• 약학회지
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• 제51권2호
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• pp.150-156
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• 2007

Some flavonoids have spasmolytic activities in various smooth muscles, but structure-activity relationships on their spasmolytic activity and its mechanism are unclear. In this study, effects of flavones (flavone and apigenin) and flavonols (quercetin and rutin) on the rat ileal smooth muscle contraction were studied in vitro and in vitro. In the electric stimulation-induced contraction, all of four flavonoids inhibited concentration-dependently the rat ileal smooth muscle contraction induced by electric stimulation (10 mV, 0.1 cps, 0.1 msec duration), IC$_{50}$ of quercetin, apigenin, flavone and rutin were 0.98${\times}$10$^{-5}$, 1.20${\times}$10$^{-5}$, 1.55${\times}$10$^{-5}$ and 1.85${\times}$10$^{-5}$ M, respectively. Flavonoids at a concentration of 2${\times}$10$^{-5}$ M also significantly inhibited the anaphylactic contraction and decreased concentration-dependently the mast cell degranulation by anaphylactic reaction, IC$_{50}$ of quercetin, apigenin, flavone and rutin were 4.0${\times}$10$^{-5}$, 7.5${\times}$10$^{-5}$, 8.0${\times}$10$^{-5}$ and 9.5${\times}$10$^{-5}$ M, respectively. These results indicated that flavones and flavonols inhibited the rat ileal smooth muscle contraction induced by electric stimulation because of their antagonism against acetylcholine and have spasmolytic activities on anaphylactic contraction which may be due to their mast cell-stabilizing activities. Furthermore, double bond of C$_{2,3}$ in benzene ring of flavonoids may be important in the their antispasmodic activities on the rat ileal smooth muscle contraction induced by electric stimulation and anaphylactic reaction.

• 농약과학회지
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• 제9권4호
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• pp.279-286
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• 2005

일련의 새로운 기질 분자로서 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpropionamide 유도체들의 구조 변화와 그에 따른 발아 전, 논피 (Echinochloa crus-galli)에 대한 제초활성과의 분자 홀로그래피적(H) QSAR 관계를 연구하였다. 그 결과로부터 높은 제초활성 화합물들이 유도된 HQSAR 모델에 의하여 예측되었다. 가장 양호한 HQSAR 모델은 분자조각 크기($7{\sim}10bin$) 조건에서 유도된 모델(VI-1)이었다. 제초활성에 관한 HQSAR 모델(VI-1)은 높은 예측성($r^2_{cv.}$ 또는 $q^2=0.646$)과 상관성($r^2_{ncv.}=0.917$)에 근거하여 양호한 통계값들을 나타내었다. 그리고 HQSAR 기여도로부터 가장 낮은 제초활성은 4-(6-chloro-2-benzoxazolyloxy)phenoxy 고리($pred.pI_{50}=-3.20$)에 의존적이었다. 특히, (X)-phenoxy-N-(R)-phenylpropionamide 유도체의 R=4-fluoro, X=isobutoxy 치환체인 4-isobutoxyphenoxy-N-(4-fluorophenyl)propionamide (P2)는 가장 높은 제초활성($pred.pI_{50}=9.12$)을 나타내는 화합물로 예측되었다.

• Applied Biological Chemistry
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• 제39권3호
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• pp.235-240
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• 1996

제초성 비치환(H) benzenesulfonyl urea 분자, 1은 sulfonyl group 인접의 amino group과 pyrimidinyl group의 N원자 사이에 회합(H-결합)된 형태(II-keto)가 제일 안정하였으며 phenyl 치환$(R_2$ 및 $R_3)$유도체, 2는 전자를 밀수록$(\sigma<0)$ LUMO(ev.)는 음의 값으로 증가하여 물 분자의 HOMO(ev.)사이에 궤도 조절반응(p<0)에따른 전형적인 친핵 반응성을 나타낸다. N-(4,6-이치환-pyrimidine-2-yl)aminocarbonyl-2-(1,1-dimethoxy-2-fluoro)ethylbenzenesulfonamides, 3 및 N-(4,6-이치환-triazine-2-yl)aminocarbonyl-2-(1,1-dimethoxy-2-리uoro)ethylbenzenesulfonamide, 4 유도체의 4,6-이치환기(X 및 Y) 와 헤테로 고리의 변화에 따른 올챙이고랭이(Scirpus juncodies.) 에 대한 제초활성은 소수성$((log\;P)_{opt.}=0.89)$이 가장 큰 영향을 미치는 요인이었다. 또한, pyrimidine-치환체, 3이 triazine-치환체, 4보다 양호한 제초활성을 나타내었으며 dimethoxypyrimidine-치환체, 3a가 가장 큰 제초활성을 보였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.44-45
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• 2010

We are currently conducting studies on culturing and biocompatibility assessment of various cells such as neural stem cells and induced pluripotent stem cells(IPS cells) on carbon nanotube (CNT), on nerve regeneration electrodes, and on silicon wafers with a focus on developing nerve integrated CNT based bio devices for interfacing with living organisms, in order to develop brain-machine interfaces (BMI). In addition, we are carried out the chemical modification of carbon nanotube (mainly SWCNTs)-based bio-nanosensors by the plasma ion irradiation (plasma activation) method, and provide a characteristic evaluation of a bio-nanosensor using bovine serum albumin (BSA)/anti-BSA binding and oligonucleotide hybridization. On the other hand, the researches in the case of "novel plasma" have been widely conducted in the fields of chemistry, solid physics, and nanomaterial science. From the above-mentioned background, we are conducting basic experiments on direct irradiation of body tissues and cells using a micro-spot atmospheric pressure plasma source. The device is a coaxial structure having a tungsten wire installed inside a glass capillary, and a grounded ring electrode wrapped on the outside. The conditions of plasma generation are as follows: applied voltage: 5-9 kV, frequency: 1-3 kHz, helium (He) gas flow: 1-1.5 L/min, and plasma irradiation time: 1-300 sec. The experiment was conducted by preparing a culture medium containing mouse fibroblasts (NIH3T3) on a culture dish. A culture dish irradiated with plasma was introduced into a $CO_2$-incubator. The small animals used in the experiment involving plasma irradiation into living tissue were rat, rabbit, and pick and are deeply anesthetized with the gas anesthesia. According to the dependency of cell numbers against the plasma irradiation time, when only He gas was flowed, the growth of cells was inhibited as the floatation of cells caused by gas agitation inside the culture was promoted. On the other hand, there was no floatation of cells and healthy growth was observed when plasma was irradiated. Furthermore, in an experiment testing the effects of plasma irradiation on rats that were artificially given burn wounds, no evidence of electric shock injuries was found in the irradiated areas. In fact, the observed evidence of healing and improvements of the burn wounds suggested the presence of healing effects due to the growth factors in the tissues. Therefore, it appears that the interaction due to ion/radicalcollisions causes a substantial effect on the proliferation of growth factors such as epidermal growth factor (EGF), nerve growth factor (NGF), and transforming growth factor (TGF) that are present in the cells.

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.923-929
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• 1995

Four crystal structures of M3-A (M3Na9-xHx-A, M=Rb or K and x=1 or 0), Rb3Na8H-A(a=12.228(1) Å and R1=0.046), Rb3Na9-A (a=12.258(3) Å and R1=0.058), K3Na8H-A (a=12.257(3) Å and R1=0.048) and K3Na9-A (a=12.257(3) Å and R1=0.052), have been determined by single crystal x-ray diffraction technique in the cubic space group Pm3^m at 21 ℃. In all structures, each unit cell contained three M+ ions all located at one crystallographically distinct position on 8-rings. Rb+ ions are 3.12 and 3.21 Å away respectively from O(1) and O(2) oxygens, about 0.40 Å away from the centers of the 8-rings, and K+ ions are 2.87 and 2.81 Å apart from the corresponding oxygens. These distances are the shortest ones among those previously found for the corresoponding ones. Eight 6-rings per unit cell are occupied by eight Na+ ions, each with a distance of 2.31 Å to three O(3) oxygens. The twelfth cation per unit cell is found as Na+ opposite 4-ring in the large cavities of M3Na9-A and assumed to be H+ for M3Na8H-A. With these noble non-framework cationic arrangements, larger M+ ions preferably on all larger 8-rings and the compact Na+ ions on all 6-rings, the bond angles in the 8-rings of M3-A, 145.1 and 161.0 respectively for (Si,Al)-O(1)-(Si,Al) and (Si,Al)-O(2)-(Si,Al), turned out to be remarkably stable and smaller, by more than 12 to 17°, than the corresponding angles found in the crystal structures of zeolites A with high concentration of M+ ions. It is to achieve these remarkably relaxed 8-rings, the main windows for the passage of gas molecules, with simultaneously maximized cavity volumes that M3-A have been selected as one of the efficient zeolite A systems for gas encapsulation.

• Biomolecules & Therapeutics
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• 제27권5호
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• pp.474-483
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• 2019

Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGF-A-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, ${\beta}$-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.