• The korean journal of orthodontics
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• v.44 no.4
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• pp.203-216
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• 2014

The purpose of the current report is to present 6-year long-term stability and 10-year follow-up data for an adult patient who was treated with a tongue elevator for relapsed anterior open-bite. The 19-year-old male patient presented with the chief complaint of difficulty in chewing his food. Collectively, clinical and radiographic examinations revealed an anterior open-bite, low tongue posture, and tongue-tie. The patient opted for orthodontic treatment alone, without any surgical procedure. A lingual frenectomy was recommended to avoid the risk of relapse, but the patient declined because he was not experiencing tongue discomfort. Initial treatment of the anterior open-bite with molar intrusion and tongue exercises was successful, but relapse occurred during the retention period. A tongue elevator was used for retreatment, because the approach was minimally invasive and suited the patient's requirements regarding discomfort, cost, and time. The appliance changed the tongue posture and generated an altered tongue force, which ultimately resulted in intrusive dentoalveolar effects, and a subsequent counterclockwise rotation of the mandible. The results showed long-term stability and were maintained for six years through continual use of the tongue elevator. The results of this case indicated that a tongue elevator could be used not only as an alternative treatment for open-bite, but also as an active retainer.

• Korean Journal of Oriental Medicine
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• v.8 no.1
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• pp.109-126
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• 2002

The herbal extract (YMT_02) is a modified herbal extracts from Yukmijihwangtang (YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as an anti-aging herbal medicine for hundred years in Asian countries. The purpose of this study is to; 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by hehavior task, 2) identify candidate genes responsible for enhancing memory by cDNA microarray and 3) assess the anti-oxidant effect of YMT_02 on PC12 cell. Memory retention abilities are addressed by passive avoidance task with Sprague-Dawley (SD) male rat. Before the training session, the rats are subdivided into four groups and administrated with YMT_02, Ginkgo biloba, Soya lecithin and normal saline for 10 days. The retention test was performed. 24 hours after the training session. The retention time of the YMT_02 group was significantly (p<0.05) delayed $({\sim}100%)$, whereas Ginkgo biloba and Soya lecithin treatment delayed 20% and 10% respectively. The hippocampi of YMT_02 and control group were dissected and mRNA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied and mRNA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Incyte rat GEMTM 2 cDNA microarray. The microarray results show that prealbumin(transthyretin), phosphotidy lethanolamine N-methyltransferase, and PEP-19 are expressed abundantly in the YMT_02 treated group. Especially, PEP-19 is a neuron-specific protein, which inhibits apoptotic processes in neuronal cell. On the other hand, transcripts of RAB15, glutamate receptor subunit 2 and CDK 108 are abundant in control group. Besides, neuronal genes involved in neuronal death or neurodegeneration such as neuronal-pentraxin and spectrin are abundantly expressed in control group. Additionally, the YMT_02 shows an anti oxidative effect in the PC12 cell. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the memory-enhancing effect of herbal extracts YMT_02, for example, anti-apoptotic, anti-oxidative, and neuroprotective effects.

• Korean Journal of Environmental Agriculture
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• v.23 no.4
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• pp.234-239
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• 2004

[ $NO_3$ ]-N and T-N removal rates of cattail wetland cells were compared with those of reed wetland cells. The examined cells were a part of a pond-wetland system composed of two ponds in series and six wetland cells in parallel. Each wetland cell was 25m in length and 6m in width. Cattails (Typha angustifolia) were transplanted into three cells and reeds Phragmites australis) into another three ones in June 2000. Water of Sinyang stream flowing into Kohung Estuarine lake located in the southern part of the Korean Peninsula was pumped into the primary pond, its effluent was discharged into the secondary pond Effluent from the secondary pond was funneled into each cell. Two cattail and reed cells were chosen for this research. Water quantity and quality of influnt and effluent were analyzed front May 2001 through October 2001. The volume of influent and effluent of the cells averaged about $20.0\;m^3/day$ and $19.3\;m^3/day$, respectively. Hydraulic retention time was approximately 1.5 days. Influent $NO_3$-N concentration for the four cells averaged 2.39 mg/L. Effluent $NO_3$-N concentration far the cattail and reed cells averaged 1.74 and 1.78 mg/L, respectively. Average $NO_3$-N retention rate for the cattail and reed cells by mass was 30 and 29%, respectively. Influent T-N concentration far the four cells averaged 4.13 mg/L. Effluent T-N concentration for the cattail and reed cells averaged 2.55 and 2.61 mgL respectively. Average T-N retention rate for the cattail and reed cells by mass was 39 and 38%, respectively. $NO_3$-N and T-N concentrations in effluent from the cattail cells were significantly low (p=0.04), compared with those from the reed cells. Cattail wetland cells were more efficient for $NO_3$-N and T-N abatement than reed ones.

• Journal of Environmental Science International
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• v.13 no.7
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• pp.675-680
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• 2004

This study was conducted to remove organics and nutrients using 2 stage intermittent aeration reactor. First reactor, using suspended microbial growth in intermittent aeration instead of anaerobic reactor in the typical BNR process, used minimum carbon source to release P, and it was possible to reduce ammonia loading going to second reactor. In the second reactor, using moving media intermittent aeration, it was effective to reduce nitrate in non-aeration time by attached microorganisms having long retention time. In aeration time, nitrification and P uptake were taken place simultaneously. From the experiment, two major results were as follows. First, the removal of organics was more than 90%, and optimum aeration/non-aeration time ratio for organic removal was corresponded with aeration/non-aeration time ratio for nitrogen removal. Second, in the first reactor, optimum aeration/non-aeration time ratio was 15/75 (min.) because it was necessary to maintain 75 min. of non-aeration time to suppress of impediment of return nitrate and to lead release of phosphate. In the second reactor, optimum aeration/non-aeration time ratio was 45/90 (min.).

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.17-24
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• 2005

This study was carried out to investigate the removal efficiency of an intermittently aerated nonwoven fabric filter bioreactor fed continuously with domestic sewage. The hydraulic retention time(HRT) of the reactor was reduced from 12 hrs to 10 hrs to 8 hrs during an experimental period of 17 months. In order to search an optimum aeration/nonaeration time ratio for the nitrogen removal at each HRT, the cycle times of 3, 2 and 1 hr were tested at the aeration/nonaeration time ratio of 1. Then, the aeration/nonaeration time ratio was changed from 50 min/70 min to 40 min/80 min to 30 min/90 min at the cycle time of 2 hr which showed the best nitrogen removal. During the experimental period, the effluent SS concentration was always below 1.2 mg/L with more than 95% of BOD removal efficiency. The highest nitrogen removal of 90.1% was observed at the aeration/nonaeration time ratio of 40 min/80 min at the HRT of 10 hr. Oxidation-reduction potential could represent the degree of the nitrification and denitrification reaction in the reactor.

• Journal of Industrial Technology
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• v.17
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• pp.73-77
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• 1997

This study aims to develop the combined septic tank for middle-small scale sewage treatment. The developed process were circular and separate type. The circular combined septic tank was controlled sludge discharge and could be modified the advanced treatment system. The separate combined septic tank was could be applicated wastewater that discharge flow was varied, and was could be maintained F/M ratio constantly. The optimum hydraulic retention time was about 16 hours.

• YAKHAK HOEJI
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• v.31 no.2
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• pp.112-115
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• 1987

Gypsogenin was derivatized with 2, 4-dinitrophenylhyclrazine prior to analysis with HPLC. Reversed-phase column (Du pont ODS) was used and the mobile phase was acetonitrile and water (60:40). The effluent was detected at 550nm using an U.V. detector and the retention time was approximately 9.2min. The concentration was quantitated by measuring the area and the detection limit was 0.2$\mu\textrm{g}$.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.144-146
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• 2003

The removal effect of total nitrogen in municipal wastewater by decreasing hydraulic retention time(HRT) from 6 hour to 4 hour on MNR process was not decreased.. The removal efficiencies of nutrient removal process combining A2/O process with media for T-N were 63.1% in the reactor operated 6 hour, and 73.5% in the reactor operated 5 hour and 77.0% in the reactor operated 4 hour.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.150-154
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• 1987

A new mixed approximation method is proposed for the model reduction of high order linear and time-invariant dynamic systems. This method makes allowance for stability and feature retention simultaneously. After defining dominant frequency range which affects relative stability of systems, a part of denominator is obtained using the energy dispersion method and tests are obtained using dominant frequency response matching method. The proposed method reflects the characteristic of the original system more faithfully and guarantees absolute stability of the reduction model.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1408-1410
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• 1997

Arrhenius plots are useful in predicting long-term use temperatures of organic materials and in choosing parameters for accelerated aging. The effects of antioxidant on the heat resistance and temperature index of EPDM rubber used for electrical insulation were investigated. The short-time points were obtained by 50% retention of elongation at break.