• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.231-235
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• 2001

The single oral toxicity of JG-381 was studied in Sprague-Dawley rats of both sexes. In this study, rats were administrated orally with dosages of 267, 400, 600, 900 and 1350 mg/kg of JG-381. We daily examined number of deaths, clinical signs, body weights and gross findings for 14 days after JG-381 administration. When we administered different doses of 267, 400, 600, 900 and 1350 mg/kg, we found 1, 4, 4, 5 and 5 male rats died and 3, 5, 4, 5 and 5 female rats died within 1 day after administration, respectively. Some clinical signs (decrease locomotor activity, salivation, soft stool, prone position, lacrimation, crouching position, convulsion, ataxic gait, incontinence of urine) were also observed during the experimental period. Our findings suggest that oral L $D_{50s}$ (95% confidence limit) for male and female rats are 327 mg/kg (270~396 mg/kg) and 250 mg/kg (256~264 mg/kg), respectively.y.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.286-291
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• 2001

As part of fundamental studies on the degradation of the organic compounds in industrial waste water, the photocatalytic degradation properties of the organic compound by means of the UV/TiO$_2$degradation process have been investigated. The test organic compound of acetic acid was chosen in this study. The testing of photo catalytic degradation were performed under various operation conditions such as TiO$_2$dosages, initial concentration of the organic, the aqueous pH's, etc. The effects of various parameters on the short time activity of the present acetic acid-UV/TiO$_2$system could be demonstrated from this investigation.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.1
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• pp.73-77
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• 2001

Objective: To report the pregnancy which was made by in vitro fertilization using recombinant follicle stimulating hormone and gonadotropin releasing hormone antagonist. Material and Method: Case report. Results: Six oocytes were retrieved and all were fertilized by intracytoplasmic sperm injection. Six embryos were transferred and the pregnancy was confirmed. Conclusion: It is envisaged that the availability of recombinant gonadotropins and gonadotropin releasing hormone antagonists will ultimately lead to shorter, cheaper and safer treatments, using reduced dosages.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.3
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• pp.312-319
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• 2004

The optimum dosage control is presumably the goal of every water treatment plant. However it is difficult to determine the dosage rate of coagulant, due to nonlinearity, multivariables and slow response characteristics, etc. To deal with this difficulty, the real number genetic-fuzzy system was used in determining the dosage rate of the coagulant. The genetic algorithms are excellently robust in complex optimization problems. Since it uses randomized operators and searches for the best chromosome without auxiliary informations from a population which consists of codings of parameter set. To apply this algorithms, we made the real number rule table and membership function from the actual operation data of the water treatment plant. We determined optimum dosages of coagulant(LAS) using the fuzzy operation and compared them with the dosage rate of the actual operation data.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.81-87
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• 1996

The purpose of this research is to examine the utilization of oyster shells for neutralization and removal of heavy metal ions in plating wastewater, because oyster shells have been known to be very porous, to have high specific surface area and to have alkaline minerals such as calcium and magnesium. The results obtianed from this research showed that oyster shells had a buffer capacity to neutralize an acidic.alkali system in plating wastewater. Generally, it could be showed that the removal efficiencies of heavy metal ions were very influenced by reaction times and oyster shell dosages. In point of ocean waste, if oyster shells substituted for a valuable adsorbent such as actviated carbon, they could look forward to an expected economical effect.

• Geomechanics and Engineering
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• v.20 no.6
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• pp.505-516
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• 2020

In recent years, Nano-technology significantly invaded the field of Geotechnical engineering, particularly in soil stabilisation techniques. Stabilisation of weak soil is envisioned to modify various soil characteristics by the addition of natural or synthetic materials into the virgin soil. In the present study, laboratory experiments were executed to investigate the influence of nano-silica particles in the consistency limits, compressive strength of the soft clay blended with cement. The results revealed that the high compressibility behaviour of soft clay modified to medium-stiff condition with fewer dosages of cement and nano-silica. The mechanism behind the strength development is verified with the previous researches as well as from Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction test (XRD) and Scanning Electron Microscopy (SEM) analysis. Based on the results, the presence of nano-silica in soft clay blended with cement has a positive effect on the behaviour of soil. This technique proves to be very economical and less detrimental to the environment.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.926-928
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• 1999

Treeing inhibitors of barbituric acid derivatives effects on the electrical properties of crosslinked low density polyethylene under radiation environments were investigated. The electrical parameters for tree inception voltage, AC breakdown strength, volume resistivity, capacitance and dissipation factor at 1MHz and thermoluminescence, gel content measurements were discussed as a function of irradiated dosages. From the results, barbituric acid among the treeing inhibitors was shown the best treeing and radiation resistance.

• Reproductive and Developmental Biology
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• v.41 no.2
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• pp.33-40
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• 2017

X-chromosome inactivation is one of the most complex events observed in early embryo developments. The epigenetic changes occurred in female X-chromosome is essential to compensate dosages of X-linked genes between males and females. Because of the relevance of the epigenetic process to the normal embryo developments and stem cell studies, X-chromosome inactivation has been focused intensively for last 10 years. Initiation and regulation of the process is managed by diverse factors. Especially, proteins and non-coding RNAs encoded in X-chromosome inactivation center, and a couple of transcription factors have been reported to regulate the event. In this review, we introduce the reported factors, and how they regulate epigenetic inactivation of X-chromosomes.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.104-111
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• 1998

This study was performed to investigate the contents of preservatives in cosmetic lotions and creams. The 55 kinds of creams and the 45 kinds of lotions were tested, and the 6 kinds of preservatives such as sorbic acid (SA), benzoic acid (BA), methlparaben(MP), ethylparaben(EP), propylparaben(PP) and butylparaben(BP) were determined for domestic and foreign cosmetics by high performance liquid chromatography(HPLC). The recovery rates of methanol extraction and distillation method were respectively the range of 84.82 - 99.62% and 17.47 - 79.91% for the spiking concentration of 1.2% in the cosmetic lotions. Excellent isolation was showed at the wavelength of 230nm for 6 kinds of preservatives. Preservatives were detected for all tested samples and their concentration were not exceeded in cosmetic combination limits. Paraoxybenzoate esters(MP, EP, PP, BP) were used in the 98.0% of samples and not less than 2 kinds of preservatives were used in samples.

• Toxicological Research
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• v.27 no.2
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• pp.119-123
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• 2011

In this research, the genotoxic effect of Picrorrhiza Rhizoma (PR) aqueous extract was evaluated using the mouse micronucleus test. PR extract was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000 and 500 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control. The appearance of a micronucleus (MN) in polychromatic erythrocyte (PCE) is used as an index for genotoxic potential, and PCE ratio is used as an index of cytotoxicity. Although significant (p < 0.01) increase of the number of PCE with one or more nuclei (MNPCE) was detected in cyclophosphamide treated groups, no significant increases of MNPCE numbers were observed in all three different dosages of PR extracts treated mice with over 0.39 of the individual polychromatic erythrocyte ratio in all mice used in this study. The results obtained indicated that PR extract shows no genotoxicity effects up to 2000 mg/kg dosing levels.