• Analytical Science and Technology
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• v.10 no.5
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• pp.378-385
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• 1997

In order to clarify the functional role of Tyr7 in human glutathione S-transferase P1-1, we extensively investigated the effect of mutation of Tyr7 on the substrate specificity and inhibition characteristics. The mutational replacement of Tyr7 with phenylalanine lowered the specific activities with 1,2-dichloro-4-nitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy) propane for GSH-conjugation reaction to 3~5% of the values for the wild-type enzyme. The pKa of the thiol group of GSH bound in Y7F was about 2.4 pK units higher than that in the wild-type enzyme. The $I_{50}$ of hematin for Y7F was similar to that for the wild-type enzyme and those of benastatin A and S-(2,4-dinitrophenyl)glutathione were only moderately decreased. These results suggest that Tyr7 is considered to be important the catalytic activities not only for GSH-chloronitrobenzene derivatives but also for GSH-epoxide conjugation reaction, rather than to binding of the substrates.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.3
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• pp.255-256
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• 1993

Recently, Ghim and Son (1993) compared the air quality impacts of two point sources P1 and P3 in Seoul in the first quarter of 1988, whose emission rates were 99.9g/s and 49.4g/s, and whose stack heights were 75m and 21m. They said that higher concentrations from P3 in the nearby area were responsible for shorter stack height of P3. But concentrations were not raised so high only because the stack height was reduced from 75m to 21m. Volume of exit gas from P3 was also much smaller than that from P1.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.409-413
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• 1996

Paracalanus parvus and P. indicus collected in Korean coastal waters were redescribed to clarify taxonomical confusion. They showed the significant morphological difference in the $2nd\~4th$ swimming legs. In P. parvus the outer distal edge of 3rd segment of exopod of $2nd\~4th$ swimming legs is not serrated. The 1st basipodite has no spinules on the surface. In P. indicus the outer distal edge of 3rd segment of exopod of End and 3rd swimming legs is serrated, while that of the 4th swimming leg is not. This species has the 1st basipodite with a lot of spinules on the surface.

• Analytical Science and Technology
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• v.5 no.3
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• pp.249-261
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• 1992

Electrochemical behavior of the heavy lanthanide complexes of alizarin red S(ARS) has been investigated by d. c. polarography, differential pulse polarography and cyclic voltammetry. The reduction mechanism at a mercury electrode of alizarin red S as a complexing ligand showed a one step of two-electron transfer and the electron process is found to be reversible. Alizarin red S forms a 3:1 adsorptive complexes with lanthanides and the complexes are reduced via one step of two-elctron. The reduction potential of complex wave($P_2$) shifted more negatively than the ligand wave($P_1$). The linear calibration curves of the decreacing $P_1$ and increasing $P_2$ is obtained when the lanthanide concentration varies from $2.0{\times}10^{-6}M$ to $6.4{\times}10^{-5}M$ under the condition of pH 9.5, 0.1M LiCl and $1{\times}10^{-3}M$ ARS.

• Journal of environmental and Sanitary engineering
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• v.21 no.1 s.59
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• pp.21-34
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• 2006

To investigate anti-HIV-1 activity of water soluble chitosans, sulfated chitosan derivatives were prepared in mild condition. Various sulfated chitosan derivatives (N-3,6-O-S-chitosan, N-desulfated 3,6-O-S-chitosan, 3,6-O-S-chitin, and 3,6-O-sulfated-N-(o-carboxybenzoyl) chitosan) were synthesized with sulfurtrioxidepyridene complex in pyridine solvent. Characterization of the sulfated chitosan derivatives was carried out by $^{13}C$ NMR and IR spectroscopies. To observe ionic reaction properties, pKas of the sulfated chitosan derivatives and chitosan of low molecular weight were estimated by potentiometric titration. The sulfated chitosan derivatives had high water solubility, pKas (pKa : 7.7) of N-3,6-O-S-chitosan and N-desulfated 3,6-O-S-chitosan were increased than pKa of water insoluble chitosan (pKa : 6.2), These results suggest the participation of electrostatic interaction of amino and sulfate groups on the sulfated chitosans. Anti-HIV-1 drugs, such as AZT, ddC, and ddI for anti-HIV activity had higher selective index compared with SCB-chitosan but N-3,6-O-S-chitosan has shown higher selective index compared with ddC and ddI as HIV drugs.. These results suggest that sulfated chitosan derivatives were expected as an anti-HIV drug with differential driving force mechanism against some nucleoside analogs drug in the future.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.1-7
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• 2004

Fenoxaprop-p-ethyl[Ethyl (R)-2-{4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy}propionate] is well known as a herbicide for its specific activity against the weed grasses. This compound was synthesized by the reaction of 4-(6-chloro-1,3-benzoxazol-2-yloxy)phenol and ethyl (S)-O-(p-toluenesulfonyl)lactate in good yields with high optical pure(optical purity: 99.9% up). In this process Walden inversion occurs, whereby the S-configuration of the propionic acid derivative is converted to the R-configuration of the final product. 4-(6-Chloro-l,3-benzoxazol-2-yloxy)phenol was obtained by 5 step reactions in over-all 70% yields using inexpensive raw materials.

• Journal of the Chungcheong Mathematical Society
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• v.27 no.3
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• pp.427-431
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• 2014

In this paper, we show that groups of order $2^npq$, where p, q are primes of the from $p=2^n-1$, $q=2^{n-1}+p$ with $n{\geq}3$, are not simple and groups of order $2^npq^t$ for $t{\geq}2$, where p, q are odd primes of the form $p=2^m-1$, $q=2^n-1$ with m < n, are not simple.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.1076-1084
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• 1995

A mixture of aluminum isopropoxide (Al(OC3H7i)3) solution and sodium hydroxide (NaOH) solution was hydrolyzed in the range between pH 1~14. the powder obtained from sol-gel process was calcined at several temperatures and crystallization behaviors of various samples were investigated. The hydrolyzed sols of pH 1~6 wre clear, or near clear. On the other hand, powder precipitated from sols of pH 7~14. The sample obtained from pH 3 solution crystallized via complicated route, and $\beta$-Al2O3 and $\beta$"-Al2O3 phases appeared at lower temperature than samples from other pH conditions. And the quantity of remained $\beta$"-Al2O3 phase after heat treatment at 150$0^{\circ}C$ was more than samples from other pH conditions. After sintering, ionic conductivities were 1.3$\times$10-4S.cm-1 to 0.76$\times$10-4S.cm-1.0-4S.cm-1.

• Korean Journal of Applied Biomechanics
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• v.23 no.4
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• pp.285-294
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• 2013

The purpose of this study was to provide fundamental information for success factors of techniques through kinematic analysis including coordination of lower extremities and landing stability according to the success and failure of $540^{\circ}$ Dwihuryeochagi in Taekwondo. Twenty Taekwondo athletes: ten success group (S, age: $22.3{\pm}1.8$ yrs, height: $172.1{\pm}5.4$ cm, body mass: $64.4{\pm}4.2$ kg) and ten failure group (F, age: $22.3{\pm}1.8$ yrs, height: $172.1{\pm}5.4$ cm, body mass: $64.4{\pm}4.2$ kg) participated in this study. Three-dimensional motion analysis using a system of 3 video cameras with a sampling of 60 fields/s was performed during the competition of $540^{\circ}$ Dwihuryeochagi. Motions were divided into five events: pivot foot landing (E1), pivot foot toe off (E2), COM max height (E3), kick impact (E4) and landing (E5). At E1, the stride width was greater for S than for F (p<.05) while the time was greater for S than for F during P4 (p<.05). At E4, knee angle was greater for S than for F (p<.05). At E5, hip angle was greater for S than for F (p<.05) while kick distance was greater for S than for F (p<.05). Furthermore, at P3, the time would be related to kicking velocity (p<.05), while at P4, the time, range of hip angle and knee angle would be related to kick distance (p<.05). At P1, COM horizontal velocity would be related to COM vertical velocity of P1 and P2 (p<.05). Based on the findings, success factors of $540^{\circ}\acute{y}$ Dwihuryeochagi were COM horizontal velocity of P1, COM vertical velocity of P2, the time, kick distance, velocity, angle of lower extremities and coordination of P3-P4.

• Journal of Sasang Constitutional Medicine
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• v.17 no.1
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• pp.84-102
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• 2005

Objectives The purpose of this study was to objectify the diagnosis of Sasang constitution. It was analyzed the adult female voices into 44 factors with PSSC-2004. Methods The study was conducted on the subjects inputted /a/ 2.5-3 sec of 217 adult women voices to PSSC-2004. The statistical analyses are applied to three groups: total group, under 55 year-old group, over 55 year-old group. The group of total 216 was composed with 8 Taeyangins, 60 Soyangins, 66 Taeumins and 83 Soeumins. The under 55 year-old group was composed with 6 Taeyangins, 53 Soyangins, 55 Taeumins and 76 Soeumins. The over 55 year-old group was composed with 2 Taeyangins, 7 Soyangins, 11 Taeumins and 7 Soeumins. Results 1. In total group and under 55 year-old one, Soeumin's center pitch were significantly high compared with the others(P=0.005)(P=0.019). It was significant for distinction between Taeumin and Soeumin at the result of post mortem. 2. In over 55 year-old group, Soeumin's center freq.(total) and center freq.(1) were significantly high compared with the others(P=0.024)(P=0.016). In under 55 year-old group, Soeumin's center freq.(4) was significantly high(P=0.025). While Taeumin's center freq.(3) in under 55 year-old group and center freq.(4) in over 55 year-old group were significantly high(P=0.049)(P=0.043). 3. In over 55 year-old group, Soeumin's APQ(center), APQ(2/5), APQ(3/5), APQ(4/5) and APQ(2/3) were significantly high compared with the others. It was significant for distinction between Taeumin and Soeumin at the result of post mortem(P=0.004) (P=0.003) (P=0.004) (P=0.013) (P=0.004). 4. In over 55 year-old group, Soeumin's APQ(1/3), APQ(1/2), APQ(2/2) and zeroover APQ were significantly high compared with the others (P=0.013) (P=0.003) (P=0.008) (P=0.012). 5. In over 55 year-old group, Taeyangin's octave 3 shimmer was significantly high compared with the others(P=0.000). 6. In under 55 year-old group, Taeyangin's total energy was significantly high compared with the others(P=0.040). 7. In under 55 year-old group, Taeyangin's zeroover energy sum was significantly high compared with the others(P=0.038). Conclusions From above result, there is the possibility of efficiency standard guide for constitutional diagnosis by analyzation of the voices.