• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.448-451
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• 2002

The possibility of using polypyrrole as a drug delivery system(DDS) has been studied using indicate (Phenol red) and substance with therapeutic activity(Sodium salicylate). In aqueous solution, negative potential is applied to polypyrrole then anion(with therapeutic activity) of sodium salicylate is released by redox processes of polypyrrole. The release amount of anionic drugs from polypyrrole is measured by UV-visible spectrometer which can measure UV-absorbance of materials. Electrode area that use for release amount measurement is$50mm^{2}(5{\times}10mm)$,and thickness of polypyrrole membrane is $15{\mu}m$. DC 1V applied in saline solution, the release amount according to time increased gradually. In various electrode area, release amount of anionic drug is directly to electrode area.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.77-78
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• 2018

Form-work is a must for construction work. In order to secure the best condition of the form surface and to increase the number of times, the form releasing agent is applied during the process of the form-work. The base oil of the form release agent which has been used already uses the oil which directly or indirectly affects the natural environment and the concrete. In this study, the basic study on the form release agent for concrete was carried out only for the effect of adhesion. The adhesive force of the tile is measured by the mortar to determine the change of the releasing agent and the adhesive strength.

• 대한소아치과학회지
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• 제25권2호
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• pp.259-267
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• 1998

For more than two decades, many investigators have tried a variety of methods for delivering antimicrobial agents to the oral cavity with the objective of eliminating mutans streptococci. In the belief that the effectiveness of chemotherapy might be improved by a more effective delivery system, the intention of the present study was to exploit a new drug delivery system delivering chlorhexidine to the oral cavity. The vehicle delivering chlorhexidine tested in this study was self-curing acrylic resin(polymethyl methacrylate). The powder of the acrylic resin was polymerized with the 5 different liquid preparations, in which $Chlorzoin^{(R)}$ was mixed with five different monomer/Chlorzoin ratios immediately prior to the polymerization, in a stainless steel mold ($40mm{\times}40mm{\times}2mm$). A total of 50 cured resin specimens were divided into 5 groups according to the different monomer preparations. Every specimen was soaked in an airtight container filled with distilled water (100 ml) and then kept in an incubator at $37^{\circ}C$. The solutions (0.8 ml) were collected from the container at every 24 hours, and the amount of released chlorhexidine in the solutions was measured in an ultraviolet spectrophotometer at 250nm. The container was refilled with distilled water every after measurement. This procedure was repeated for 14 days. It was found that chlorhexidine was continuously released from all of the 50 specimens during the experimental period. And it was noted that the pattern of chlorhexidine release was a type of sustained-release preparation, that is, the amount of the released chlorhexidine at the first day in all 5 groups was high (p<0.0001), and then the release was decreased during the rest of the experimental period (p<0.001).

• 환경영향평가
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• 제8권1호
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• pp.107-120
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• 1999

This study was performed to survey the general feature of reservoir sediment in Daecheong, Sapkyo and Kumkang reservoir. For investigations, sediments were sampled at four sites in Dae-Cheong and two sites in SapKyo and Kumkang in June and October. The items for investigation are as follows; water content, loss on ignition(IG), porosity of sediment, contents of element such as hydrogen, nitrogen, carbon, phosphorus contents and nutrient release rates. Loss on ignition was measured to determine the contents of organic substance. And its ranges were determined 2.4~16.2% in Daecheong reservoir, 5.6~27.9% in Sapkyo and 4.8~18.7% in Kumkang reservoir. And, total phosphorus contents in sediments were measured $677{\sim}5,238{\mu}g/g$ in Daecheong, $780{\sim}1,417{\mu}g/g$ in Sapkyo and $604{\sim}1,452{\mu}g/g$ in Kumkang reservoir. And release rates of nutrients were calculated $0.05{\sim}8.63mgP/m^2day$ and $4.99{\sim}36.56mgN/m^2day$ in Daecheong, $1.83{\times}10^{-3}{\sim}3.23{\times}10^{-2}mgP/m^2day$ and $1.97{\sim}.22mgN/m^2day$ in Sapkyo, $8.31{\times}10^{-3}{\sim}6.51{\times}10^{-2}mgP/m^2day$ and $0.89{\sim}4.42mgN/m^2day$ in Kumkang reservoir, respectively. And this study attempted to determine the humus level of sediments. As a result of elemental analysis, C/N ratio was determined 3.0~13.1 in Daecheong reservoir, 6.5~13.0 in Sapkyo and 3.6~12.6 in Kumkang reservoir, respectively. From the elemental analysis, humus levels of reservoirs were changed from mesohumic to oligohumic state in all reservoirs.

• Asian-Australasian Journal of Animal Sciences
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• 제10권6호
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• pp.599-602
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• 1997

Fluctuation of fungal zoospores on agar strips were observed in the rumen of sheep fed three different levels of dietary concentrate, timothy hay: concentrate = 3:0 (AF diet), timothy hay: concentrate = 2:1 (MC diet), timothy hay : concentrate = 1:2 (HC diet) respectively. The number of zoospores on the strip was drastically decreased after morning feed with AF diet. The number was the highest at 0 h ($1.34{\times}10^2/cm^2$), then declined to $2.0{\times}10^3/cm^2$ at 9 h after feeding. In the rumen of animals fed MC diet, the number of zoospores decreased with time after feeding, although the decrement was slower than that with AF diet. During 0-3 h after feeding, number of zoospores was $1.6{\times}10^4/cm^2$. Although the number slightly decreased at 6 and 9 h, relatively high levels were maintained. It seems that the inducers for zoospore-release were maintained at relatively high concentration throughout incubation period. The fluctuation pattern of number of germinated zoospores was different in the rumen of animals fed HC diet from those of AF and MC diets. The number of zoospores was constantly maintained at lower level ($1.0{\times}10^3/cm^2$) than the other diets. For MC diet, continuous high number of germinated zoospores may be due to the continuous release of zoospores by hemes in timothy hay and concentrate feed, and by unknown mechanisms. Unlike AF diet which promoted relatively rapid decline of zoosporogenesis, supplementation of concentrate feed to the timothy hay did not promote such rapid decline of zoosporogenesis. It was suggested that release of inducers for zoosporogenesis from concentrate feed persisted longer time than from timothy hay. HC diet promoted the lowest zoospore production, suggested the lowest fungal population size in this experiment. These results show that an appropriate amount of concentrate may support fungal growth and stimulate zoosporogenesis in the rumen.

• 대한물리의학회지
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• 제15권1호
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• pp.85-94
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• 2020

PURPOSE: This study examined the effects of the meridian muscle release technique on the pain and functional movement of patients with myofascial pain syndrome (MPS) of the shoulder joint. METHODS: The subjects of this study included 45 patients with MPS of the shoulder joint. The subjects were divided randomly into the following groups; the meridian muscle release technique group (n=15), the Graston technique group (n=15), and the control group (n=15). Both the meridian muscle release group and the Graston technique group received conventional therapy for 35 minutes initially and were then treated using the meridian muscle releases technique and Graston technique for 10 minutes, respectively. The control group received only conventional therapy for 35 minutes. All three groups underwent treatments three times a week for four weeks. Each subject was evaluated randomly using the VAS, PPT, SPADI and ROM both before and after treatment. RESULTS: The Graston technique group showed a significantly more substantial increase in functional movement (p<.05) than the meridian muscle release technique and control groups. The meridian muscle release technique group had significantly less pain (p<.05) compared to the Graston technique and control groups. CONCLUSION: These findings suggest that the meridian muscle release technique can be useful for decreasing pain and increasing the functional movement of patients with MPS of the shoulder joint.

• Journal of Pharmaceutical Investigation
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• 제23권3호spc1호
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• pp.9-18
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• 1993

Sugar spheres loaded with melatonin (MT) were coated with $Aquacoat^{\circledR}$ to control the release rate of MT over 8 hours. A zero-order release pattern over 8 hours was obtained with 20% coating on 8-10 mesh beads in USP basket dissolution studies. MT in 20% coated beads was quite stable at room temperature with less than 5% MT degraded during 6 months' storage. Dissolution profiles were also unchanged after 6 months. An oral preparation containing MT-loaded uncoated beads for immediate release and 20% coated beads with $Aquacoat^{\circledR}$ for controlled release over 8 hours was evaluated in six human subjects. When total 0.5 mg MT as low dose (immediate release portion of MT, 0.1 mg) was administered to four subjects, average peak plasma MT concentration was reached at about 600 pg/ml and maintained at about 10 pg/ml over 8 hours. Plasma MT concentration-time profiles were similar in shape to computer-simulated profiles. However, maximal plasma MT concentrations were three times greater compared to computer simulated curve. These results suggest that MT dose, ratio of immediate and controlled release MT, and pharmacokinetic parameters selected are adjusted to mimic endogenous MT concentration-time curve. In another study, 0.2 mg MT having 10% of immediate release portion and 80% controlled release portion produced plasma MT concentration-time curve which is more similar to endogenous profiles. A low bioavailability (<20%) may result from extensive first pass metabolism and remaining amounts of MT from controlled beads. A good correlation between plasma MT concentration and urinary excretion rate of 6-sulphatoxymelatonin (6-STMT), a major metabolite of MT was observed. As plasma MT concentration increased, urinary excretion rate of 6-STMT increased concomitantly. The linear relation between plasma MT and urinary excretion rate of 6-STMT was statistically significant. This result suggests that urinary 6-STMT may be used as an index of circadian rhythms of MT in humans.

• The Korean Journal of Physiology and Pharmacology
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• 제3권4호
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• pp.393-404
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• 1999

We have reported that hypoxia stimulates EDRF(s) release from endothelial cells and the release may be augmented by previous hypoxia. As a mechanism, it was hypothesized that reoxygenation can stimulate EDRF(s) release from endothelial cells and we tested the hypothesis via bioassay experiment. In the bioassay experiment, rabbit aorta with endothelium was used as EDRF donor vessel and rabbit carotid artery without endothelium as a bioassay test ring. The test ring was contracted by prostaglandin $F_{2a}\;(3{\times}10^{-6}\;M)$ which was added to the solution perfusing through the aorta. Hypoxia was evoked by switching the solution aerated with 95% $O_2/5%\;CO_2$ mixed gas to one aerated with 95% $O_2/5%\;CO_2$ mixed gas. Hypoxia/reoxygenation were interexchanged at intervals of 2 minutes (intermittent hypoxia). In some experiments, endothelial cells were exposed to 10-minute hypoxia (continuous hypoxia) and then exposed to reoxygenation and intermittent hypoxia. In other experiments, the duration of reoxygenation was extended from 2 minutes to 5 minutes. When the donor aorta was exposed to intermittent hypoxia, hypoxia stimulated EDRF(s) release from endothelial cells and the hypoxia-induced EDRF(s) release was augmented by previous hypoxia/reoxygenation. When the donor aorta was exposed to continuous hypoxia, there was no increase of hypoxia-induced EDRF(s) release during hypoxia. But, after the donor aorta was exposed to reoxygenation, hypoxia-induced EDRF(s) release was markedly increased. When the donor aorta was pretreated with nitro-L-arginine $(10^{-5}$ M for 30 minutes), the initial hypoxia-induced EDRF(s) release was almost completely abolished, but the mechanism for EDRF(s) release by the reoxygenation and subsequent hypoxia still remained to be clarified. TEA also blocked incompletely hypoxia-induced and hypoxia/reoxygenation-induced EDRF(s) release. EDRF(s) release by repetitive hypoxia and reoxygenation was completely blocked by the combined treatment with nitro-L-arginine and TEA. Cytochrome P450 blocker, SKF-525A, inhibited the EDRF(s) release reversibly and endothelin antgonists, BQ 123 and BQ 788, had no effect on the release of endothelium-derived vasoactive factors. Superoxide dismutase (SOD) and catalase inhibited the EDRF(s) release from endothelial cells. From these data, it could be concluded that reoxygenation stimulates EDRF(s) release and hypoxia/reoxygenation can release not only NO but also another EDRF from endothelial cells by the production of oxygen free radicals.

• 한국가스학회지
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• 제11권4호
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• pp.98-103
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• 2007

발생가능성 분석은 염소공정의 염소투입설비에서 누출 가능성을 교정하는데 자주 사용되고 있다. 그리고 이러한 시설은 전형적으로 압력용기, 기화기, 배관, 측량장비, 안전장치로 등으로 구성되어 있다. 이 논문에서는 가능성 분석절차와 기계적 요소들의 고장률에 대하여 사건 시나리오를 만들 인적오류도 고려하였다. 논문의 주된 목적은 결정된 각각의 시나리오의 발생가능성을 계산하는 것으로 발생가능성분석 방법에 근거하여 기계요소의 고장률과 인적오류를 포함하여 계산하였다. 그 결과, 주요 $Cl_2$ 취급공정에서 누출이 발생할 가능성이 $5.73{\times}10^{-5}$로 예측되었으며 세정시스템의 고장확률은 $4.11{\times}10^{-2}$로 나타났다.

• 대한정형도수물리치료학회지
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• 제23권2호
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• pp.75-81
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• 2017

Background: The purpose of this study is to examine the effects of myofascial release technique (MFR) on psychological and physical symptom in somatization with post traumatic stress disorder (PTSD). Based on this, proceed to present an effective physical treatments. Methods: In this study, three subjects were applied ABA design for a total of 12 weeks. Intervention was performed three times per week, and only MFR for 6 weeks was applied to the patient for 60 minutes. General physical therapy consisted of a total of 60 minutes including hot pack, electric therapy, and ultrasound. In this study, we measured three times in the second baseline stage at the initial evaluation before the commencement of intervention, somatization, depression, anxiety, sleep disorder, and pain after 6 weeks and 12 weeks. Results: In this study, the application of MFR showed significant differences in somatization symptoms, sleep disturbance, and headache. There was no significant difference in depression and anxiety. Conclusions: As a result, the application of MFR in PTSD patients with somatization can be suggested as a useful intervention to resolve the psychosomatic problem.