• Bulletin of the Korean Chemical Society
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• 제24권8호
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• pp.1141-1149
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• 2003

The structures and gas-phase ionization energies (ΔG°) of Meldrum's acid (I) and related cyclic (II-VI) and acyclic compounds (VII-IX) are investigated theoretically at the MP2/6-31+$G^*$, B3LYP/6-31+$G^*$, B3LYP/6- 311+$G^{**}$, B3LYP/6-311++G(3df,2p) and G3(+)(MP2) levels. Conformations of three neutral cyclic series vary gradually from boat (Meldrum's acid, I), to twisted chair (II) and to chair (III) as the methylene group is substituted for the ether oxygen successively. The preferred boat form of I can be ascribed to the two strong $n_O$ → σ* c-c antiperiplanar vicinal charge transfer interactions and electrostatic attraction between negatively charged C¹ and positively charged C⁴at the opposite end of the boat. All the deprotonated anionic forms have half-chair forms due to the two strong $n_C$ → π* c=0 vicinal charge transfer interactions. The dipole-dipole interaction theory cannot account for the higher acidity of Meldrum's acid (I) than dimedone (III). The origin of the anomalously high acidity of I is the strong increase in the vicinal charge transfer ($n_C$ → π* c=0) and 1,4-attrative electrostatic interactions (C¹↔C⁴) in the ionization (I → $I^-$ + $H^+$). In the acyclic series (VII-IX) the positively charged end atom, C⁴, is absent and the attractive electrostatic stabilization (C¹↔C⁴) is missing in the anionic form so that the acidities are much less than the corresponding cyclic series.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3553-3560
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• 2010

A new hydrazone derivative compound has been synthesized and characterized by IR, $^1H$-NMR, $^{13}C$-NMR and UV-vis. spectroscopy techniques, elemental analysis and single-crystal X-ray diffraction (XRD). The new compound crystallizes in monoclinic space group C2/c. In addition to the crystal structure from X-ray experiment, the molecular geometry, vibrational frequencies and frontier molecular orbitals analysis of the title compound in the ground state have been calculated by using the HF/6-31G(d, p), B3LYP/6-311G(d, p) and B3LYP/6-31G(d, p) methods. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the observed experimental bands. To determine conformational flexibility, molecular energy profile of (1) was obtained by semi-empirical (AM1) calculation with respect to a selected degree of torsional freedom, which was varied from $-180^{\circ}$ to $+180^{\circ}$ in steps of $10^{\circ}$. Molecular electrostatic potential of the compound was also performed by the theoretical method.

• 생명과학회지
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• 제14권4호
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• pp.593-607
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• 2004

유해성 적조생물 Cochlodinium polykrikoides/Gyrodinium aurelum을 포함한 43 종류의 와편조류를 대상으로 SSU 부위 유전자를 분석했다. 유전자 염기서열에 의거한 상호 계통수는 parisomny, distance, maxium 방법으로 실행했다. Noctilura scintillans, Gonyaulax spinifera와 Crythecodinium cohnii 종들은 와편모조류 중 가장 유전적으로 먼 것으로 보였다. Alexandrium과 Symbiodinium 종간의 bootstrap는 70% 이상의 상호 단일 계통도를 보인 반면에, Gymnodinium과 Gyrodinium은 근립절약계수와 최대 유사도 방법에서 다형 계통도를 나타내었다. Gyroddinium aurelum과 G. dorsum/G. galathenum의 유전적 분화율은 7.4% (45 bp) 였고, G. aurelum과 G. mikimotoi 상호간에는 0.9% (5bp) 밖에 나타나지 않았다. 또한 C. polykrikoides와 G. aurelum도 5.2% (31bp)로 낮은 유전적 분화율을 보였다. 계통도를 분석한 결과 G. aureolum과 C. polykrikoides는 Gyrodinium 보다 Gymnodinim 속에 훨씬 더 근접하게 나타났다.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.1025-1028
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• 2010

• Journal of Biosystems Engineering
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• 제31권3호
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• pp.168-174
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• 2006

The purpose of this study is to develop the cold chain system by developing optimal phase change materials (PCM). There are some benefits from developing this system such as keeping freshness of agriculture products, saving energy, etc. The major results are as follows. To decide a latent heat material, the characteristics of water, sodium, polyacrylate, ethanol and N-tetradecane are analysed. Also, an insulating material is made by mixing water, nucleating agent and latent heat material, using cementing method. In addition, the sensitivity analysis for developed latent heat material($K_l,\;K_2,\;K_3$) is conducted. For $K_l,\;K_2,\;K_3$ which cans keep latent heat temperature, ranging from $0\;to\;5^{\circ}C,\;5\;to\;10^{\circ}C,\;10\;to\;15^{\circ}C$. it can keeps latent heat temperature at radiant heat (5, 12, $17^{\circ}C$) and transportation latent heat container both melting temperature and amount of latent heat of Kl are $-1.6{\pm}1.0^{\circ}C$, 326.51 J/g, respectively and freezing temperature and latent heat are $-7.98{\pm}1.5^{\circ}C$ and 174.18 J/g. and $K_2$ are $7.41{\pm}1.5^{\circ}C$, 89.80 J/g, respectively and freezing temperature and latent heat are $-2.14{\pm}1.5^{\circ}C$ and 83.90 J/g. and $K_3$ are $9.54{\pm}1.0^{\circ}C$, 145.42 J/g, respectively and freezing temperature and latent heat are $0.21{\pm}1.0^{\circ}C$ and 152.48 J/g.

• 대한수학회보
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• 제31권2호
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• pp.289-295
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• 1994

Let (A,G,.alpha.) be a $C^{*}$-dynamical system. In [3] the classical notions of ergodic properties of topological dynamical systems such as topological transitivity, minimality, and uniquely ergodicity are extended and analyzed in the context of non-abelian $C^{*}$-dynamical systems. We showed in [2] that if G is a compact group, then minimality, topological transitivity, uniquely ergodicity, and weakly ergodicity of the $C^{*}$-dynamical system (A,G,.alpha.) are equivalent.alent.

• Applied Biological Chemistry
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• 제48권3호
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• pp.207-211
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• 2005

본 연구에서는 식물생장억제미생물 B. subtilis IJ-31이 생산하는 HCA의 최적생산조건을 검토하였다. HCA생산 최적조건으로 탄소원은 1%의 미강, 질소원은 0.5% tryptone, 무기염은 0.1% $ZnCl_2$, 배양 온도는 $37^{\circ}C$, 배양시간은 60시간, pH는 7.0에서 $90.5\;{\mu}g/ml$의 HCA를 생산하였으므로 이를 최적생산조건으로 확립하였다. 이를 바탕으로 통계프로그램(SAS) 중 반응표면 분석법(RSM)을 이용한 jar fermentor 배양에서의 HCA 최적생산 조건을 확립하였다. 즉 토양추출물 2.24% 첨가, 교반속도 290 ppm, tryptone 0.83% 첨가, 배양온도 $37^{\circ}C$, 배양시간 60시간, pH 7.0에서 $102.99\;{\mu}g/ml$의 HCA를 생산하는 최적생산 조건으로 예측되었다. 따라서 실제 상기 RSM 최적 조건에서 실험한 결과 HCA는 $102.5\;{\mu}g/ml$를 생산하였다. 이러한 결과는 플라스크에서 HCA는 $90.5\;{\mu}g/ml$로 생산되었으나 jar fermenter 배양에서는 플라스크 배양에 비하여 12%가량 HCA 생산량이 증가된 결과를 보여주는 것이다.

• Journal of Preventive Medicine and Public Health
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• 제28권4호
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• pp.863-873
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• 1995

This report describes a preperation and characterization of canine blood lead(Pb) standard reference material(SRM). Three adult beagle dogs(A, B, and C)were orally dosed with gelatin capsules containing $Pb(NO_3)_2$, equivalent to $10\sim80mg$ Pb/kg body weight. Blood was drawn 24 hours after the dose from the cephalic vein into lead free 500ml Pyrex beaker in which EDTA.K was contained as an anticoagulant. The amount of lead given to individual dog was varied arbitrarily. Three month later, 3 canine animals were orally dosed with lead secondarily to make mixed SRM(D1) which was mixed different concentrations of lead in bloods with A1, B1, and C1 in vitro. The SRMs for A, B, C, A1, B1, C1, and D1 were distributed 2ml each into more than 300 lead free bottles, and were stored in refregerator at $4^{\circ}C$. The amount of lead in canine whole blood samples were determined using a Varian 30A atomic absorption spectrophotometer(AAS) with a model GTA-96 graphite tube atomizer with D2 background correction and a Hitachi Z-8100 AAS with Zeeman background correction. The sensitivity and detection limits for lead determination of Varian 30A were $0.46{\mu}g/L,\;0.34{\mu}g/L,\;and\;0.56{\mu}g/L,\;0.14{\mu}g/L$ of Hitachi Z-8100, respectively. Day to day variations in determination of blood lead concentration in a certain sample were $31.11{\pm}1.36{\mu}g/100ml$ by Varian 30A, and $33.08{\pm}0.82{\mu}g/100ml$ by Hitachi Z-8100, showing the difference of 3% between the two results. At the blood lead concentrations of $56.31{\pm}1.98{\mu}g/100ml(A),\;40.89{\pm}0.80{\mu}g/100ml(B),\;59.01{\pm}1.38{\mu}g/100ml(C)$, the precisions of replicated measurements by AAS were 3.52%, 1.96%, and 2.34%, respectively. Coefficient variation(CV) of SRMs(A, B, and C) within a standard sample were ranged from 0.92% to 7.50%, and those between 5 standard samples were 1.21%, 2.64%, and 1.11%, respectively, showing inter-vial variation of $1{\mu}g/100ml$. Lead levels in SRMs during one month storage were unchanged. The overall recoveries were $89.6\sim100.4%,\;91.6\sim101.9%,\;90.3\sim100.0%$ for A, B, and C SRMs, means were $56.46{\pm}2.69{\mu}g/100ml,\;39.35{\pm}1.89{\mu}g/100ml,\;57.40{\pm}2.31{\mu}g/100ml$, and measurement ranges were$52.88{\pm}59.26{\mu}g/100ml,\;37.47{\pm}41.68{\mu}g/100ml,\;54.80{\pm}60.69{\mu}g/100ml$, respectively. Those results were laid within confidence limits values. The lead concentrations in the mixed sample(D1) stored over one month period were ranged from $32.76{\mu}g/100ml\;to\;33.54{\mu}g/100ml$, with CV ranging from 1.2% to 2.7%. The results were similiar to each of single samples(A1, B1, and C1) in respect of homogeneity and stability. Results of the mixed blood sample analysed after 1 month storage at $4^{\circ}C$ by four other laboratories(L1, L2, L3, L4) were similar with those of our laboratory($L5;31.18{\pm}0.24{\mu}g/100ml$, acceptable range by $CDC;25.18\sim37.18{\mu}g/100ml$), showing the concentrations of $25.91{\pm}1.19{\mu}g/100ml(L1),\;34.16{\pm}0.22{\mu}g/100ml(L2),\;35.68{\pm}0.85{\mu}g/100ml(L3),\;30.95{\pm}0.46{\mu}g/100ml(L4)$ in a each samples.

• 한국식품위생안전성학회지
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• 제31권3호
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• pp.210-215
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• 2016

본 연구에서는 국내산 고려엉겅퀴를 건강기능식품 소재로 활용시 기초자료 제공하고자 주요 산지별 pectolinarin 함량, 총 플라보노이드 함량, DPPH라디칼 소거능 및 ORAC 지수 등을 분석하였다. 산지별 고려엉겅퀴의 pectolinarin 함량은 $3.95{\pm}0.05{\sim}7.29{\pm}0.07mg/g$로 강원도 D농장(GW-D)에서 가장 높은 함량을 보였다. 총 플라보노이드 함량은 산지별로 $40.42{\pm}0.91{\sim}76.70{\pm}2.24mg\;PNE/g$ 수준으로 전라남도 A농장(JN-A) 추출물에서 가장 높은 함량을 나타내었고 강원도 A농장(GW-A) 추출물에서($40.42{\pm}0.91mg\;PNE/g$)로 가장 낮은 함량을 보였다. DPPH 라디칼 소거능의 경우, 산지별로 31.25% ~ 81.93%의 활성을 보였고, ORAC 지수는 산지별로 $179.62{\sim}514.49{\mu}M\;TE/g$로 강원도 D농장(GW-D)과 강원도 E농장(GW-E)에서 각각 514.49, $501.73{\mu}M\;TE/g$ 으로 가장 높은 ORAC 수치를 나타내었다. 결론적으로 고려엉겅퀴 추출물은 pectolinarin과 유용성분을 함유하고 DPPH 라디칼 소거능 및 ORAC 활성 등의 항산화활성을 갖는 것으로 나타났다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8963-8967
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• 2014

Background: Colon cancer is one of the most common cancers worldwide. Apoptosis is a necessary physiological process for cell elimination which is very important both cellular homeostasis and cell proliferation and differantiation. Dysregulation can lead to uncontrolled cell growth and tumor development. Survivin, a member of the IAP family, plays a key role in promotion of cell proliferation as well as inhibition of apoptosis in cancer cells. The aim of this study was to investigate whether specific genetic polymorphisms of survivin could be associated with colon cancer development and progression in a Turkish population. Our study is the first to our knowledge to investigate the relationship between colon cancer risk and survivin gene polymorphisms. Materials and Methods: The relation between colon cancer and survivin -31 G/C (rs9904341), -241 C/T (rs17878467) and -625 C/G (rs8073069) polymorphism in promotor site of survivin gene associated with apoptosis was investigated using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: Individuals with -31C allele and CC genotype were found to have a higher risk of developing colon cancer (OR=13.4, p=0.01). The -241 CT genotype considerably increased the risk of colon cancer (OR=12.0, p=0.0001). However, there was no significant varaition of the survivin -625 C/G polymorphism among colon cancer patients and controls in our study. Conclusions: This study provides the first evidence that survivin -31 G/C and -241 C/T SNP significantly contribute to the risk of colon cancer in the Turkish population.