• Title/Summary/Keyword: stability period

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The Effect of Light on the Stability of IV admixture with 5-Fluorouracil (정맥주사제 혼주시 5-fluorouracil의 차광유무에 따른 안정성에 관한 연구)

  • Lee, Eun Kyung;Suh, Okkyung;Lee, Suk Hyang;Shin, Hyun Taek
    • Korean Journal of Clinical Pharmacy
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    • v.7 no.1
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    • pp.45-49
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    • 1997
  • The effect of the light on the stability of 5-fluorouracil admixture was investigated. Four sets of 5-fluorouracil admixture were prepared using 50 mg/ml injection in $5\%$ dextrose solution in PVC bags and glass bottles: (1) 5-fluorouracil 1 mg/ml concentration in glass bottles, (2) 5-fluorouracil 1 mg/ml in PVC bags, (3) 5-fluorouracil 10 mg/ml in glass bottles, and (4) 5-fluorouracil 10 mg/ml in PVC bags. In each set, one group was protected from the light (control group) and the other group was exposed to the fluorescent light (study group). All admixtures were stored at room temperature for 72 hours. Also, 5-fluorouracil injections (50 mg/ml) were prepared in plastic syringes. Half of the samples of 50 mg/ml concentration were protected from the light (control group) and the other half were exposed to the fluorescent light (study group). These were stored at room temperature for 48 hours. After visual inspection, the pHs of each admixture were determined. The 5-fluorouracil concentrations were measured by high-performance liquid chromatography with UV detection, with 5-bromouracil as an internal standard. Over the study period, no visual changes were observed. The pHs of 5-fluorouracil admixtures were in the range of $8.2\~8.5$. The peak area ratios (5-FU/5-BrU) of 5-fluorouracil admixtures protected from the light were compared with those of the admixtures exposed to the light. There was no statistically significant difference between two groups during the study period (p>0.05). In conclusion, 5-fluorouracil admixtures in $5\%$ dextrose solution exposed to the light were stable for 72 hours.

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The Effect of Oregano and Cinnamon Essential Oils on Fermentation Quality and Aerobic Stability of Field Pea Silages

  • Soycan-Onenc, Sibel;Koc, Fisun;Coskuntuna, Levent;Ozduven, M. Levent;Gumus, Tuncay
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.9
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    • pp.1281-1287
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    • 2015
  • This study was performed to determine the effect of field pea silages which were the organic acid (OA) alternative of oregano and cinnamon essential oils on fermentation quality and aerobic stability. Whole crop pea was harvested at full pod stage and wilted in the laboratory at the 48 h. The chopped pea was mixed and divided into equal portions allocated to five groups: CON (non-treated), distilled water, denoted as control group; OA group, a mixture of 60% formic acid, 20% sodium formate and 20% water applied at a rate of 5 g/kg fresh forage (Silofarm Liquid, Farmavet); origanum (ORE) group, Origanum onites essential oil at 400 mg/kg fresh forage; cinnamon (CIN) group, cinnamon essential oil at 400 mg/kg fresh forage; origanum+cinnamon (ORECIN) group, a mixture of ORE and CIN applied at an equal rate of 400 mg/kg fresh forage. Cinnamon decreased acetic acid (AA), ammonia nitrogen ($NH_3-N$) and weight loss (WL) at the end of 60 days silage. Crude protein (CP) and dry matter (DM) increased by cinnamon essential oil. Yeasts were not detected in any treatments, including the control, after 7 days of air exposure. The $CO_2$ amount decreased and the formation mold was inhibited in the aerobic period by the addition of cinnamon oil. Oregano did not show a similar effect, but when it was used with cinnamon, it showed synergic effect on AA and during aerobic period, it showed antagonistic effect on mold formation and DM losses. It was found in this study that cinnamon can be an alternative to organic acids.

Comparison of Thermal Stability of Alkali Refined and Esterified Rice Bran Oils (알칼리 정제(精製)와 에스테르화에 의한 미강유의 열안정성(熱安定性)의 비교(比較))

  • Kim, Hyun-Ku;Shin, Dong-Hwa;Shin, Hyo-Sun
    • Korean Journal of Food Science and Technology
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    • v.17 no.3
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    • pp.180-185
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    • 1985
  • The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were compared for their thermal stabilities at $150^{\circ}C$ and $180^{\circ}C$, respectively. The acid value gradually increased in ARBO during heating period but increased slowly in ERBO-2 and declined gradually in ERBO-1. The peroxide value was somewhat fluctuated during heating period, and the maximum peroxide value in all samples was 13.3 meq/kg. TBA value was sharply increased for the first 10 hr. heating and slowed down thereafter for all samples but ERBO were intensely colored after the heat treatment. The TG ratio of the oils after 90 hr. heating was not different at $150^{\circ}C$ but ERBO was 2-7% higher ratio of TG than ARBO at $180^{\circ}C$. The oxidative stability of ARBO was twice higher than ERBO according to the result of active oxygen test.

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Effects of Branched Dextrin on the Quality Characteristics of Frozen Soft Roll Dough and its Bread during Storage (분지 덱스트린 첨가가 냉동 소프트롤 반죽 및 빵의 저장 중 품질 특성에 미치는 영향)

  • Park, Jin-Hee;Lim, Chun-Son;Kim, Il-Hwan;Kim, Mun-Yong
    • Korean journal of food and cookery science
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    • v.27 no.5
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    • pp.507-522
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    • 2011
  • In this study, samples of wheat flour and dough were prepared by adding of 1, 3, or 5% branched dextrin, which is produced from the amylopectin of waxy corn starch using a cyclization reaction with a branching enzyme. The samples were then evaluated qualitatively in terms of farinogram, viscogram, and extensogram characteristics. The fermentation power of dough expansion, extensogram characteristics, specific volume, baking loss, external/internal surface appearance, and sensory qualities were also examined after 4 weeks of storage at -20$^{\circ}C$ to determine the effect on freeze-thaw stability and quality improvement of branched dextrins in the soft roll bread formulation. Furthermore, the samples along with a control were compared regarding their quality characteristics, including changes in moisture content, water activity, color, and textural characteristics during a storage period of 4 days at 20$^{\circ}C$ to determine the effect on preventing retrogradation of the branched dextrin. As the branched dextrin content increased, area and extensibility increased, whereas water absorption, fermentation power of dough expansion, resistance/extensibility ratio, baking loss, and brownness of the crust decreased. However, the control group presented significantly higher peak viscosity, resistance, specific volume, taste, overall acceptability, moisture content, water activity, springiness, cohesiveness, and resilience values than those of the branched dextrin samples, whereas lightness, hardness, and chewiness showed the reverse effect. As the storage period increased, lightness, hardness, and chewiness increased, whereas cohesiveness decreased. In conclusion, the results indicate that adding 1~3% branched dextrin into a soft roll bread formulation from frozen dough had no positive effect on freeze-thaw stability or preventing retrogradation but may provide good nutritional properties.

Assessment of the Toxicity and the Stability of Saeng Mak San by Using Repeated Intravenous Injections in Sprague-Dawley Rats

  • Lee, Hwa-Young;Kim, Sungchul;Cho, Seung-Hun
    • Journal of Pharmacopuncture
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    • v.19 no.3
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    • pp.231-238
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    • 2016
  • Objectives: This study used repeated intravenous injections of Saeng Maek San (SMS) injection in Sprague-Dawley (SD) rats to assess the toxicity and the stability of SMS. Methods: Six-week-old male and female SD rats reared by Orient bio Inc were chosen for this pilot study. They were randomly split into four groups: Group 1 (G1), the control group (0.3 mL of normal saline solution/day/animal), and Groups 2, 3 and 4 (G2, G3 and G4), the experimental groups (0.1, 0.2 and 0.3 mL/day/animal of SMS), respectively. Each animal received an intravenous injection of SMS once a day for four weeks. Clinical signs, body weight changes, and food consumption were monitored during the observation period, and urinalysis and hematology were conducted after four weeks of SMS or saline administration. Results: No deaths occurred in any of the four groups during the observation period. Compared to the control group, male and female rats in groups 3 and 4 (0.2 and 0.3 mL/animal/day) showed hemoglobinuria, but the low-dosage group (G2, 0.1 mL/animal/day) showed no significant changes in the clinical signs test. No significant changes due to SMS were observed in the experimental groups regarding body weight changes, food consumption urinalysis, or hematology. Conclusion: During this study, no mortalities were observed in any of the experimental groups and no hemoglobinuria was observed in the low dosage group (0.1 mL/animal/day) while it was intermittently observed in groups 3 and 4 (0.2 and 0.3 mL/animal/day). Thus, we suggest that the no-observed adverse-effect level (NOAEL) is 0.1 mL/animal/day in male and female SD rats.

Effect of the sampling time of high-frequency ZOH and a physical damper on stable haptic interaction (고주파 영차홀드의 샘플링 주기와 물리적 댐퍼가 안정적인 햅틱 상호작용에 미치는 영향)

  • Lee, Kyungno
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.649-654
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    • 2019
  • Stable haptic interaction with virtual environments is essential not only for the safety of the user but also for improving the immersion of the user. If the coefficient of a virtual spring is increased, the system becomes unstable. Therefore, the coefficient of the virtual spring is limited. The haptic system with the high-frequency zero-order-hold (HF-ZOH) is proposed to enhance the stability margin of a virtual spring. In this paper, the relationship among the sampling period of HF-ZOH, the coefficient of the physical damper, and the maximum stable margin of the virtual spring is analyzed. The lager the coefficient of the physical damper is, the shorter the sampling period of the HF-ZOH is, the larger the stable region of the virtual spring becomes. If the ratio N is larger than 40, the stable region of the proposed method is about three times to eight times that of the previous method, according to the coefficient of the physical damper. Hence the method enables to improve the user's realism in virtual environments.

Evaluation of the Effect of Traffic Control Program on the Ambient Air Quality in Seoul Metropolitan Area Using the Lower Level Stability Index of Atmosphere (하층대기의 연직 안정도 지표를 이용한 차량 2부제의 수도권 대기오염도 저감효과 분석)

  • Kim C.-H.;Park 1.-S.;Lee S.-J.;Kim J.-S.;Hong Y.-D.;Han J.-S.;Jin H.-A.
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.2
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    • pp.243-257
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    • 2005
  • The effects of Traffic Control Program (TCP) on the ambient urban air quality of SO$_{2}$, NO$_{2}$, O$_{3}$, and PM$_{10}$ were evaluated in Seoul metropolitan area by using the lower atmospheric vertical stability index and daily mean wind speeds. The vertical stability index; temperature lapse rate between 1000 hPa and 850 hPa geopotential height fields, were used to identify daily vertical stability index during the 2002 World Cup period where traffic amount was reportedly reduced to half the number of vehicles. The indicated air quality levels of TCP days were then compared with those of the cases observed with analogous vertical stability during the recent 3 years from 2000 to 2002. The result indicates that the effect of TCP on the primary air pollutants are found to be approximately 39$\%$, 23$\%$ and 20$\%$ lower for SO$_{2}$, NO$_{2}$ and PM$_{10}$, respectively. The secondary air pollutant; ozone, showed relatively smaller decreasing rate (13$\%$) of daily mean concentrations (even increased during the night time). The comparison of daily maximum or peak concentrations reveals that the pronounced decreasing effects of TCP on the ambient air quality for both primary and secondary air pollutants, suggesting that TCP is one of the effective strategies to control peak or higher concentrations for most urban scale air pollutants in and around the Seoul metropolitan area.

Stability Analysis for a Virtual Spring Model with an Extrapolation and High-frequency ZOH (외삽법과 고주파 영차홀드 출력이 포함된 가상 스프링 모델의 안정성 영역 분석)

  • Lee, Kyungno
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.12-17
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    • 2018
  • In order to enhance the realism of a virtual environment, a method of maximizing the stiffness of the virtual environment model is needed, which maintains the stability of the haptic system. In our previous research, we proposed a haptic system with a first order hold, instead of a zero order hold, and showed that the maximum available stiffness of a virtual spring with the first-order hold is larger than that with the zero-order hold. However, in terms of real system implementation, the zero order hold is a more common and easy method. In this paper, we propose an extrapolation method and a high frequency zero-order-hold output method in order to obtain the stability region using a zero order hold, which is equivalent to the method using the first-order-hold. The simulation results shows that the stability range of the virtual spring becomes almost the same as that of the method using the first order hold when the sampling period of the high frequency zero-order-hold method is decreased. Moreover, the stability range of the proposed method is several times to several tens of times greater than that of the method using the zero order hold only. Therefore, it is expected that the proposed method can enhance the realism of rigid bodies in a virtual environment.

THE EFFECT OF DIFFERENT SURFACE TREATMENT ON THE OSSEOINTEGRATION AND STABILITY OF IMPLANTS (처리 방법이 다른 표면이 임플랜트의 골유착 및 안정성에 미치는 영향)

  • Yang, Seoung-Wook;Lim, Heon-Song;Cho, In-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.44 no.5
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    • pp.606-616
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    • 2006
  • Purpose: This experiment examined the effect of different surface treatment on the osseointegration and stability of implants. Material and methods: In this study, 40 each of machined, SLA and RBM implants, which are the most commonly used implants, were implanted into the tibia of 20 normal rabbits using $OsseoCare^{TM}$. The rabbits were sacrificed after 1 week, 4 weeks, 8 weeks and 12 weeks for implant stability analysis, removal torque analysis, histologic and histomorphometric analysis. Result : ISQ showed significant difference between Machined and RBM at first week and at 4 weeks. There was significant difference between Machined and both SLA and RBM(p<0.05) but after 8 weeks there were no significant difference between each group. In the removal torque, RBM showd significantly higher values than SLA and Machined surface at 1st week. At 4th and 12th week, there was significant difference between Machined and SLA, RBM(p<0.05). In the bone to implant contact variable, there was no significant difference between each surface treatment method. In the Machined surface group, there was no significant difference between each time interval. but in SLA group, there were significant differences between the 1st week and 12th week and in RBM group, there were significant differences between the 1st week and 8th, 12th week and between 4th and 12th week(p<0.05). The bone area showed significantly higher values in SLA and RBM compared to Machined surface 1st and 8th week and significantly higher values in SLA than Machined surface at the 4th week(p<0.05). Conclusion: The roughened surface of implants showed positive effect in the early stages of implantation and assisted in bone formation After the bone formation stage, there was no statistical difference between Machined and roughened surface groups. In dental implantation, where initial stability is critical to the success of implants, the use of roughened surface implants should assist in reducing the healing period after implantation.

The Effect of Bacterial Inoculants and a Chemical Preservative on the Fermentation and Aerobic Stability of Whole-crop Cereal Silages

  • Filya, Ismail;Sucu, Ekin
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.378-384
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    • 2007
  • Three microorganisms and one chemical preservative were tested for their effects on the fermentation and aerobic stability of whole-crop wheat, sorghum and maize silages. Wheat at the early dough stage, sorghum at the late milk stage and maize at the one-third milk line stage were harvested and ensiled in 1.5-l anaerobic jars untreated or after the following treatments: control (no additives); Lactobacillus plantarum (LP) at $1.0{\times}10^6$ colony-forming units (CFU)/g of fresh forage; L. buchneri (LB) at $1.0{\times}10^6$ CFU/g; Propionibacterium acidipropionici (PA) at $1.0{\times}10^6$ CFU/g; and a formic acid-based preservative (FAP) at 3 ml/kg of fresh forage weight. Three jars per treatment were sampled on d 90 after ensiling, for chemical and microbiological analysis. At the end of the ensiling period, 90 d, the silages were subjected to an aerobic stability test lasting 5 d. In this test, $CO_2$ produced during aerobic exposure was measured along with chemical and microbiological parameters which serve as spoilage indicators. The silages inoculated with LP had higher concentration of lactic acid compared with the controls and the other treated silages (p<0.05). The controls and LP-inoculated silages spoiled upon aerobic exposure faster than LB, PA and FAP-treated silages. The controls and LP-inoculated silages spoiled upon aerobic exposure faster than LB, PA and FAP-treated silages due to more $CO_2$ production (p<0.05) in these two groups and development of yeasts unlike the other groups. In the experiment, the silages treated with LB, PA and FAP were stable under aerobic conditions. However, the numbers of yeasts was higher in the LP-inoculated wheat, sorghum and maize silages compared with the LB, PA and FAP-treated silages. The LB, PA and FAP improved the aerobic stability of the silages by causing more extensive heterolactic fermentation that resulted in the silages with high levels of acetic and propionic acid. The use of LB, PA and FAP as silage additives can improve the aerobic stability of whole-crop wheat, sorghum and maize silages by inhibition of yeast activity.