• 한국산학기술학회논문지
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• 제19권3호
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• pp.601-613
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• 2018

본 연구는 스마트시티 공간에 적용된 디바이스/기술과 아티팩트의 융합유형을 도출 하는데 목적을 두고 있다. 주요연구 내용은 스마트시티에 적용된 환경기술(ET), 정보기술(IT), 환경 정보기술(ET+IT)의 융합 변화에 관한 심층 분석 이다. 연구결과는 다음과 같다. 첫째, 31개의 사례분석을 통해 디바이스/기술과 아티팩트를 아래와 같이 도출 하였다. 아티팩트는 총 92개, 디바이스/기술은 환경기술 중심에서 83개, 정보기술 중심에서 51개, 총 134개 디바이스/기술 이다. 둘째, 디바이스/기술과 아티팩트 간의 융합 변화는 7개 유형에 의해 진화하고 있다. 유형1, 'ET중심의 진화형' 은 1기(분리융합), 2기(ET중심융합), 3기(ET중심으로 IT성장과 ET+IT융합) 이다. 유형2, 'ET+IT중심의 ET고도화형'은 1기(초기 ET+IT융합), 2기(ET 고도화, IT보조융합), 3기(ET 초고도화, IT보조융합) 이다. 유형3, 'ET+IT 일체화형'은 1기(ET, IT 개별융합), 2기(ET+IT 혼합융합), 3기(ET+IT 일체화 융합) 이다. 유형4, 'IT중심의 진화형'은 1기(IT중심으로 개발), 2기(IT중심의 고도화), 3기(IT중심의 초고도화) 이다. 유형5 6, 'ET+IT 동반 고도화형'은 1기(ET+IT중심의 IT개발), 2기(ET+IT중심의 IT고도화), 3기(ET+IT중심의 IT 초고도화) 이다. 유형7, 'ET+IT중심의 IT고도화형'은 1기(초기 ET+IT융합), 2기(ET보조융합, IT고도화), 3기(ET 보조융합, IT 초고도화) 이다. 본 결과는 향후 다양한 새로운 융합유형이 도출될 것이라 예상 된다.

• 생명과학회지
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• 제13권5호
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• pp.684-691
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• 2003

솔잎 EtOAc획분을 하루 25, 50, 100 mg/kg체중으로서 SD계 랫트에 45일동안 투여하여 간장획분의 세포막 유동성(membrane fluidity MF), 기초 및 유도활성산소(BOR 및 IOR), 산화적 스트레스로서 과산화지질(lipid peroxide : LPO) 및 산화단백질(oxidized protein : OP), 그리고 리포푸신(lipofuscin : LF)의 축적에 미치는 영향을 평가하여 보았다. 솔잎 EtOAc획분의 투여에 의하여 간장의 mitochondria 및 microsome획분에서 어느 정도 MF가 증가하였지만, 유의성은 EtOAc-100 투여그룹의 mitochondria획분에서만 인정되었다. 기초 및 유도활성산소로서 BOR 및 IOR의 생성 억제효과는 간장의 두 획분의 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 활성산소의 생성 억제 효과가 인정되었다. 산화적 스트레스에 미치는 영향에서는 mitochondria획 분에서 는 EtOAc-100투여그룹에서, 그리고 microsome획분에서는 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 LPO의 생성 억제효과가 인정되었고, mitochondria 획분에서는 EtOAc-50 및 EtOAc-100투여그룹에서 유의적인 OP의 생성 억제효과가 인정되었지만, microsome 획분에서는 아무런 유의성도 인정할 수 없었다. 그렇지만, 간장의 클로로포름층에서 측정한 LF의 축적은 EtOAc-25, EtOAc-50 및 EtOAc-100 투여그룹에서 다같이 유의적인 LF의 축적 억제효과가 인정되었다. 이상의 결과에서 평가하여 볼 때 솔잎 EtOAc획분의 투여는 간장의 유동성을 촉진하고 산화적 스트레스를 효과적으로 억제할 수 있을 것으로 기대된다.

• 한국가축번식학회지
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• 제24권4호
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• pp.343-346
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• 2000

Transgenic animals are very useful for scientific, pharmaceutical, and agricultural purposes. In livestock, transgenic technology has been used forth genetic alteration of farm animals, the production of human proteins inlarge quantities in the milk of transgenic farm animals (Clark et al., 1989; Ebert et al., 1991; Kimpenfort et al., 1991; Wall et al., 1991; Kimpenfort et al., Well et al,m 1991; Hill et al., 1992; Velander et al., 1994; Chen et al.), and the generation of animals with organs suitable for xenotransplantation (Pinkert, 1994; Chen et al., 1999). (omitted)

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.117-121
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• 2008

Pseudo-first-order rate constants (kobsd) have been measured spectrophotometrically for nucleophilic substitution reactions of 5-nitro-8-quinolyl benzoate (5) with alkali metal ethoxides, EtO?M+ (M+ = Li+, Na+ and K+) in anhydrous ethanol (EtOH) at 25.0 0.1 C. The plots of kobsd vs. [EtO?M+] exhibit upward curvatures, while the corresponding plots for the reactions of 5 with EtO?Na+ and EtO?K+ in the presence of complexing agents, 15-crown-5-ether and 18-crown-6-ether are linear with rate retardation. The reactions of 5 with EtO?Na+ and EtO?Li+ result in significant rate enhancements on additions of Na+ClO4, indicating that the M+ ions behave as a catalyst. The dissociated EtO and ion-paired EtOM+ have been proposed to react with 5. The second-order rate constants for the reactions with EtO (kEtO) and EtOM+ (kEtOM+) have been calculated from ion-pairing treatments. The kEtO and kEtOM+ values decrease in the order kEtONa+ > kEtOK+ > kEtOLi+ > kEtO, indicating that ion-paired EtOM+ species are more reactive than the dissociated EtO ion, and Na+ ion exhibits the largest catalytic effect. The M+ ions in this study form stronger complex with the transition state than with the ground state. Coordination of the M+ ions with the O and N atoms in the leaving group of 5 has been suggested to be responsible for the catalytic effect shown by the alkali metal ions in this study.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.21-24
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• 2003

In general, to enhance physical properties of PET-layered silicate nanocomposites $(P_{et}LSNs)$, it has been well known that the organic modifiers should introduce into gallery regions. However, the organic modifiers in$(P_{et}LSNs)$ may result in thermal decomposition by melt processing at high temperature, and it necessarily lead to deteriorate various physical properties of final products. Therefore, in this study, $(P_{et}LSNs)$ excluding and including organic modifiers were prepared by solution method $(S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom})$ and we (focused on the effects of the organic modifiers in $P_{et}$ LSNs with exfoliation structure on the crystallization behaviors, the optical transparency, the thermal stability and the mechanical property. The absence and existence of organic modifiers in $S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom}$ were investigated by EA and TGA, and nano-structure of silicate layers in $S-P_{et}LSNs$ was evaluated by using WXRD, SAXS and TEM. $S-P_{et}LSNs_{eom} and S-P_{et}LSNs_{iom}$ were mixed with neat PET as masterbatches by melt method $(M-P_{et}LSNs_{eom} and M-P_{et}LSNs_{iom})$, and also neat PET was mixed with organically modified layered silicates (OLS) by conventional direct melt method $(D-P_{et}LSNs) at 270^{\circ}C$. As results, it was found that $M-P_{et}LSNs_{eom}, M-P_{et}LSNs_{iom}, and D-P_{et}LSN$ showed a exfoliated structure and exhibited faster crystallization rate, better thermal stability and mechanical property than those of neat PET due to the dispersed and detaminated silicate layers in PET matrix. Whereas, considering organic modifiers effect, $M-P_{et}LSNs_{eom} and D-P_{et}LSN$ exhibited slower crystallization rate, poorer optical, thermal and mechanical properties, in comparison to $M-P_{et}LSNs_{eom}> due to the thermal decomposition of organic modifier in $D-P_{et}LSNs$ during melt method.

• Bulletin of the Korean Chemical Society
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• 제17권9호
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• pp.840-845
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• 1996

Rate constants have been measured spectrophotometrically for the reactions of p-and m-nitrophenyl 2-thiophenecarboxylate (5a and 5b, respectively) with alkali metal ethoxides (EtO-M+) in absolute ethanol at 25.0±0.1 ℃. The reactivity of EtO-M+ exhibits dependence on the size of alkali metal ions, i.e. the reactivity of EtO-M+ toward 5a decreases in the order EtO-K+ ≥ EtO-Na+ > EtO-Li+ > EtO-, while the one toward 5b does in the order EtO-Na+ ≥ EtO-K+ > EtO-Li+ > EtO-. This result indicates that ion paired EtO-M+ is more reactive than dissociated EtO-, and alkali metal ions form complexes with the substrate more strongly at the transition state than at the ground state. The catalytic effect shown by alkali metal ions appears to be less significant in the reaction of 5 than in the corresponding reaction of 4, indicating that complexation of alkali metal ions with 5 is not as strong as the one with 4.

• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.565-572
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• 1997

In the freshly isolated rat nephron, the effect of endothelin-1, -2 and -3 (ET-1, -2 and -3) on cytosolic free calcium concentration ($[Ca^{2+}]_i$) was determined using the fluorescent indicator Fura-2/AM. $[Ca^{2+}]_i$ increase was investigated in 9 parts of the single nephron including glomerulus (Glm), $S_1,\;S_2,\;S_3$, cortical and medullary thick ascending limb and cortical (CCT) and outer medullary collecting tubule (OMCT). Endothelins increased $[Ca^{2+}]_i$ in Glm (ET-1; $127{\pm}17%$, ET-2; $93{\pm}5%$, ET-3; $169{\pm}17%$), CCT (ET-1; $30{\pm}6%$, ET-2; $38{\pm}19%$, ET-3; $158{\pm}18%$) and OMCT (ET-1; $197{\pm}11%$, ET-2; $195{\pm}11%$, ET-3; $215{\pm}37%$) at 10-7 M. In OMCT, ET-1 and ET-2 increased $[Ca^{2+}]_i$ in a dose-dependent manner ($10^{-10}{\sim}10^{-6}$ M). To the contrary, ET-3-induced $[Ca^{2+}]_i$ rise was begun from $10^{-12}$ M. BQ-123Na, an antagonist of ETA receptor, at $10^{-4}$ M inhibited about 30% of $[Ca^{2+}]_i$ rise induced by ET-1 and -3. Binding experiments using $[^{125}I]ET-3$ showed the existence of $ET_B$ receptor in OMCT. This binding was replaced by ET-1, ET-2 or ET-3 by the almost same degree but not by angiotensin II or vasopressin.

• 생명과학회지
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• 제13권5호
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• pp.692-698
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• 2003

뇌 세포막 유동성의 촉진 및 LPO생성의 억제효과는 중풍 등 뇌혈관질환을 억제할 수 있을 뿐만 아니라 혈관성치매의 예방에도 크게 기여할 것으로 기대된다[26,18]. 따라서 솔잎 EtOAc획분을 하루 25, 50, 100 mg/kg BW로써 SD계 랫트에 45일동안 투여하여 뇌조직중의 세포막 유동성 (membrane fluidity : MF), 기초 및 유도활성산소(BOR 및 IOR), 산화적 스트레스로서 과산화지질(lipid peroxide : LPO) 및 산화단백질(oxidized protein : OP), 그리고 리포푸신(lipofuscin : LF)의 축적에 미치는 영향을 평가하여 보았다. 솔잎 EtOAc획분의 투여에 의하여 뇌조직의 mitochondria 및 microsome획분에서 용량의존적으로 MF가 증가효과가 나타났지만, EtOAc-100 투여그룹의 mitochondria 획분에서만 약 10%의 유의적인 MF의 증가효과가 인정되었다. 뇌조직의 mitochondria에서 기초 및 유도활성산소로서 BOR 및 IOR의 생성은 EtOAc-50 및 EtOAc-100투여그룹에서 각각 9.2∼10.2% 및 17.1∼24.0%의 유의적인 억제효과가 인정되었고, microsomes에서 BOR 및 IOR의 생성은 EtOAc-50및 EtOAc-100투여그룹에서 각각 11.6∼16.6% 및 12.1∼16.1%의 유의적인 억제효과가 인정되었다. 산화적 스트레스에 미치는 영향은 mitochondria 및 microsomes획분에서 EtOAc-50 및 EtOAc-100투여그룹에서 각각 8.5∼12.0% 및 11.6∼18.5%의 유의적인 LPO의 생성 억제효과가 인정되었지만, 뇌조직의 두 획분에서 OP의 생성은 EtOAc획분의 용량의존적으로 억제되었지만, 유의성은 인정할 수 없었다. 또한 뇌조직에서 LF의 축적도 EtOAc획분의 용량 의존적으로 억제효과가 나타났지만, 유의성은 인정할 수 없었다. 이상의 결과에서 평가하여 볼 때 솔잎 EtOAc획분의 투여는 뇌조직의 유동성을 촉진하고 LPO의 생성을 효과적으로 억제할 수 있지만, 현재의 투여농도에서는 OP 및 LF의 생성을 방지할 수 없을 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1951-1956
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• 2011

A kinetic study is reported on nucleophilic substitution reactions of 4-nitrophenyl nicotinate 5 and isonicotinate 6 with alkali metal ethoxide EtOM (M = K, Na, and Li) in anhydrous ethanol at $25.0{\pm}0.1^{\circ}C$. Plots of pseudo-first-order rate constant $k_{obsd}$ vs. EtOM concentration exhibit upward curvature for the reactions of 5 and 6 with EtOK and EtONa but are almost linear for those with EtOLi. Dissection of $k_{obsd}$ into $k_{EtO^-}$ and $k_{EtOM}$ (i.e., the second-order rate constant for the reaction with dissociated $EtO^-$ and ion-paired EtOM, respectively) has shown that $k_{EtOK}$ ${\geq}$ $k_{EtONa}$ > $k_{EtO^-}$ but $k_{EtOLi}$ < $k_{EtO^-}$. It has been concluded that $K^+$ and $Na^+$ ions catalyze the reactions by increasing the electrophilicity of the carbonyl carbon atom through formation of a 4-membered cyclic transition state $TS_3$ or $TS_4$. However, $M^+$ ion catalysis has been found to be much less significant for the reactions of 5 and 6 than for the corresponding reactions of 4-nitrophenyl picolinate 4, which was reported to proceed through a 5-membered cyclic transition state $TS_2$. Although 5 and 6 are significantly more reactive than 4-nitrophenyl benzoate 3, the reactions of 5 and 6 result in smaller $k_{EtOK}/k_{EtO^-}$ ratios than those of 3. The electron-withdrawing ability of the nitrogen atom in the acyl moiety of 5 and 6 has been suggested to be responsible for the increase in reactivity and the decrease in the $k_{EtOK}/k_{EtO^-}$ ratio.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1789-1793
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• 2014

Pseudo-first-order rate constants ($k_{obsd}$) have been measured spectrophotometrically for the reactions of 5-nitro-8-quinolyl nicotinate (4) and 5-nitro-8-quinolyl isonicotinate (5) with alkali metal ethoxides (EtOM; M = K, Na and Li) in anhydrous ethanol at $25.0{\pm}0.1^{\circ}C$. The plots of $k_{obsd}$ vs. [EtOM] curve slightly upward for the reactions with EtOK and EtONa but are linear for the reactions with EtOLi and for those with EtOK in the presence of 18-crown-6-ether. Dissection of $k_{obsd}$ into $k_{EtO^-}$ and $k_{EtOM}$ (i.e., the second-order rate constants for the reactions with the dissociated $EtO^-$ and ion-paired EtOM, respectively) has revealed that the reactivity increases in the order $EtO^-{\approx}EtOLi$ < EtOK < EtONa for the reactions of 4 and EtOLi < $EtO^-$ < EtOK < EtONa for the reactions of 5. Comparison of the kinetic results for the reactions of 4 and 5 with those reported previously for the corresponding reactions of 5-nitro-8-quinolyl benzoate (2) and picolinate (3) has revealed that the esters possessing a pyridine ring (i.e., 3-5) are significantly more reactive than the benzoate ester 2 due to the presence of the electronegative N atom (e.g., 2 << 3 < 4 < 5). It has been concluded that $M^+$ ion catalyzes the reactions of 3-5 by increasing the electrophilicity of the reaction center through a five-membered cyclic transition state (TS) for the reaction of 3 and via a four-membered cyclic TS for the reactions of 4 and 5.