• Archives of Pharmacal Research
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• v.12 no.1
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• pp.1-4
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• 1989

6-Arylamino-3,7-dihydro-3,7-dimethy-2-oxo-1H-purine and 2-arylimino-6-arylamino-3,7-dihydro-3,7-dimethyl-1H-purine were obtained in a one-pot reaction when 3,7-dihydro-3,7-dimethyl-1H-purine-3,6-dione, phosphorus pentaoxide, triethylamine hydrochloride and appropriate amine amino are heated at $170^{\circ}$. Some derivatives were tested for their antitumor activity.

• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1224-1231
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• 2006

The stability and control derivatives of DURUMI-lI UAV using the flight test are obtained. The flight test data is gathered from the normal flight condition (normal mode) and the flight condition assumed as the right elevator fixed (fault mode). Using real-time parameter estimation techniques, applied to Fourier transform regression method, simulates the aircraft motion. From the result, the fault of control surface is to be detected. In this paper, the results of the real- time parameter estimation techniques are compared with the results of the Advanced Aircraft Analysis (AAA). Using the aerodynamic derivatives, it provides the base line of normal/failure for the control surface by using the on-line parameter estimation of Fourier transform regression. In flight, this approach maybe helpful to detect and isolate the fault of primary control surface. It is explained how to perform the flight condition assumed as the right elevator fixed in the flight test. Also, it is mentioned how to switch between the normal flight condition and the assumed fault flight condition.

• Journal of Life Science
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• v.12 no.5
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• pp.505-514
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• 2002

The aim of this study was to evaluate the anticonvulsant activity of four agents derived from tropinone (T-1: 2,4-dipyrrolylmethenylnortropinone, T-2: 2,4-diphenylmethenylnortropinone, T-3 : 2,4-difurfurylmethenylnortropinone, T-4 : 2,4-dimethoxyphenylmethenylnortropinone) in NIH Swiss mouse. Pentylenetetrazole (nZ) was injected via intraperi-toniurn in mouse and Maximal Electroshock (MES) stimulation was through both conjunctivas by electrodes. Tropinone derivatives were treated at 15 minutes before PTZ or MES procedure. PIZ of 25 mg/kg induced generalized seizure in mouse, effects of tropinone derivatives on PTZ-induced seizure were monitored. Compared with control group, T-4 decreased seizure grade most effectively. Also T-4 increased onset time of PTZ-induced seizure. This result showed that T-4 is most effective on PTZ-induced seizure. In MES-induced seizure, T-1 decreased seizure grade and recovery time. nNOS expression in hippocampus and cortex were increased in nZ- and MES-induced seizure animals compared with control. Pretreatment of tropinone derivatives in PTZ-induced seizure did not affected nNOS expression in brain tissues, but T-1 and T-4 decreased nNOS expression in cortex of MES-induced seizure animals. These findings suggest that tropinone derivatives have specific anticonvulsant activities according to PTZ- and MES-induced seizure. 2,4- dimethoxyphenylmethenylnoroopinone is most effective in PTZ-induced seizure and 2,4-di methoxyphenylmethenylnortropinone is most effective in MES-induced seizure.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.221-224
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• 2004

The feeding group, composed of weaning pigs fed 3 mL of glucosamine derivatives, was compared for the carcass and quality characteristics with the unfeeding control group for 25∼70 days since they were born. The results were as follows; There were no significant differences in carcass weight and back-fat thickness between the feeding group and the unfeeding group although the feeding group had low ranges of standard error when compared to the control. Feeding group had higher incidence frequencies of A grade (42.7%) than the control (29.2%). The feeding group and unfeeding group had no significant differences in meat color, cooking loss, WBS, pH, WHC and purge loss. Results from this study showed that feeding GD had effect on the decrease the market weight and production of consist carcass weight, however, the feeding GD had no effect on pork quality during rearing times after weaning.

• Natural Product Sciences
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• v.13 no.4
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• pp.378-383
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• 2007

Phenathrene derivatives, such as batatasins, are well-known constituents in Dioscorea Rhizoma. Although phenanthrenes have been reported as representative compounds in this plant, standard markers for quality control have been focused on the polar constituents (saponins and purine derivatives). Herein, simple, rapid and reliable HPLC method was developed to determine 3,5-dimethoxyphenanthrene-2,7-diol (DMP) and batatasin-I (BA-I) as non-polar standard maker compounds of Dioscorea Rhizoma. DMP and BA-I were analyzed under optimized HPLC conditions [column: Columbus $5{\mu}$ C18 100A ($30{\times}4.6mm$ i.d., $5{\mu}m$; mobile phase: $H_2O$ with 0.025% $CH_3COOH$ (v/v) for solvent A and $CH_3CN$ with 0.025% $CH_3COOH$ (v/v) for solvent B, gradient elution; flow rate: 2 mL/min; detection: 260 nm), and each experiment was finished within 13 min. Good linearity was achieved in the range from 0.5 to $10.0{\mu}g/mL$ for each compound, and intra- and inter-day precision were in the acceptable levels. The recovery test were performed with three different Dioscorea Rhizoma samples (D. opposita, D. batatas and D. japonica), and showed its accuracy values in the range of 97.2 - 102.8% for three different concentrations of DMP and BA-I. The content levels of DMP and BA-I were ranged under 0.0020%. These results demonstrated that amounts of DMP and BA-I are easily determined with conventional HPLC-UV-DAD method although the content levels were lower than those of saponins and allantoin in Dioscorea Rhizoma. This HPLC method could be used for quality control of various Dioscorea preparations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.644-651
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• 2021

Viral hemorrhagic septicemia virus (VHSV) is a fish pathogen responsible for causing enormous economic loss to the aquaculture industry not only in Korea but worldwide. Thus, it is necessary to identify natural compounds that can be used to control the spread of VHSV. In this study, the anti-VHSV activities of five catechol derivatives, i.e., catechol, pyrogallol, 3-methyl catechol, veratrole, and 3-methyl veratrole-extracted from green tea-were assessed. The antiviral activities of these derivatives were found to be dependent on their structure, i.e., the hydroxyl or methoxyl group and their substituent groups-on the benzene ring. Catechol, pyrogallol, and 3-methyl catechol exhibited relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities than veratrole, and 3-methyl veratrole. Moreover, 3-methyl catechol harboring a methyl substituent group increased the viability of the virus-infected cells and resulted in a 2.86 log reduction in the gene copies of VHSV N (per mL) in real-time PCR analysis. In conclusion, the catechol derivatives harboring hydroxyl groups in their benzene ring exhibited higher antioxidant activities than those harboring the methoxyl groups. However, catechol derivatives with a methyl group at the 3'-position of the benzene ring exhibited higher antiviral activity than those harboring a hydroxyl group. To our knowledge, this is the first study to evaluate the relationship between the structure and the anti-VHSV activity of catechol derivatives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1120-1127
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• 2007

This study was designed to examine the effects of n-6 PUFA rich corn oil, n-3 PUFA rich perilla oil and their conjugated double bond derivatives on serum lipids status in rats. Experimental diets containing lard (control), corn oil (CO), perilla oil (PO), conjugated double bond derivatives of n-6 PUFA rich corn oil (TCO) and n-3 PUFA rich perilla oil (TPO) at the level of 10% (w/w) were fed to male Sprague Dawley rats for 4 weeks. TCO was found to have three derivatives of linoleic acid and TPO had five derivatives of linolenic acid by GC. Serum total cholesterol levels were significantly lower in the all experimental groups than in the control group, and particularly, the lowest in TCO and TPO groups. HDL-cholesterol concentrations were a little higher in the all experimental groups than in the control group, and TCO and TPO groups were not significantly different from CO and PO groups. Serum LDL, LDL-cholesterol, chylomicron and triglyceride concentrations were significantly lower in the all experimental groups than in the control group, remarkably lower in TCO group and particularly, the lowest in the TPO group. Serum free cholesterol and cholesteryl ester concentrations were lower in TCO and TPO groups than in CO and PO groups. From the above research, TCO and TPO groups were effective on the improvement of the lipid compositions in serum and particularly, TPO group was the most effective on the improvement of serum lipids.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.101-108
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• 2002

A numerical simulation of an incompressible cavity flow is conducted. Two dimensional Navier-Stokes equations are integrated using staggered grid and a finite volume method with C-QUICK scheme for spatial derivatives and fully implicit scheme for the time derivatives. SIMPLE-C algorithm is employed to solve the pressure field. Computational results show that the third eddy is generated in the shear layer mode but not in the steady mode. This signifies that the third eddy plays an important role in cavity flow stability. As a means to control the flow, jet blowing is applied to a position below the cavity upstream edge. Effects of flow control parameters on the stability such as the frequency, the phase, and the velocity magnitude are reported.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.215-229
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• 2005

In this paper, constraint aggregation is combined with the adjoint and multiple shooting strategies for optimal control of differential algebraic equations (DAE) systems. The approach retains the inherent parallelism of the conventional multiple shooting method, while also being much more efficient for large scale problems. Constraint aggregation is employed to reduce the number of nonlinear continuity constraints in each multiple shooting interval, and its derivatives are computed by the adjoint DAE solver DASPKADJOINT together with ADIFOR and TAMC, the automatic differentiation software for forward and reverse mode, respectively. Numerical experiments demonstrate the effectiveness of the approach.

• Journal of Navigation and Port Research
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• v.39 no.3
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• pp.173-178
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• 2015

In these days, the world has been increasing the development of various underwater vehicles such as ROVs (Remotely operated underwater vehicles) and AUVs (Autonomous underwater vehicles). And the importance of submarine's maneuverability is especially being emphasized. Therefore, accurate values of the derivatives in equations of motion are required to control motion of the submarines. The aims of the present study are to experimentally derive Hydrodynamic derivatives derived by the vertical planar motion mechanism (VPMM) model test, and to estimate vertical dynamic stability was estimated by using the linear hydrodynamic derivatives, the hydrodynamic derivatives of the submarine, which have a high propriety, were provided by using the fourier analysis of measured forces and moments. Furthermore it is confirmed that the experimental derivatives shows well agreement with the theoretical estimations, and the dynamic stability of the submarine was estimated as a good state, which implies that the value is greater than zero.