• Title/Summary/Keyword: Effective Dose Rate

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Propofol Patient-Controlled Sedation Using $Perfusor^{\circledR}$ fm (B. Braun, Germany) Infusion Pump in Dental Patients-Preliminary Study (치과 환자에서의 $Perfusor^{\circledR}$ fm 자가통증조절기를 이용한 Propofol 자가진정조절법)

  • Park, Chang-Joo;Yum, Kwang-Won;Kim, Hyun-Jeong
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.2 no.2 s.3
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    • pp.97-100
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    • 2002
  • Background: Patient-controlled sedation (PCS) has been blown for a safe and effective sedative method on the same pharmacological concepts of patient-controlled analgesia. Many different kinds of infusion devices have been used but they often have too long nominal infusion rate and lockout time. $Perfuser^{\circledR}$ fm (B. Braun, Germany) is a new PCA device with 999.9 ml/hr nominal infusion rate and minimum 1 min lockout time. In this study, the feasibility of propofol PCS using $Perfuser^{\circledR}$ fm was examined in order to provide a safe satisfactory sedation for dental patients. Methods: Eleven healthy patients presenting for oral surgery were studied. Propofol PCS was performed using $Perfuser^{\circledR}$ fm, which was set to deliver a bolus dose of 5 mg with 999.9 ml/hr nominal infusion rate and 1 min lockout time. Propofol loading dose was randomly assigned to a bolus dose ${\times}$ 0, 2, and 3 (initial bolus). Patients were told to press the bolus button as often as they needed to relieve discomfort. Results: Total infused dose of propofol was mean 1.8 mg/kg/hr and D (Delivery)/A (Attempt) ratio was mean 72.8%. All patients was awake and there were no clinically significant intraoperative side effects during the sedation. Almost all patients were very satisfied with this type of PCS. Conclusion: Propofol PCS using $Perfuser^{\circledR}$ fm infusion pump provided good conscious sedation for dental procedures.

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Detection Limit of a NaI(Tl) Survey Meter to Measure 131I Accumulation in Thyroid Glands of Children after a Nuclear Power Plant Accident

  • Takahiro Kitajima;Michiaki Kai
    • Journal of Radiation Protection and Research
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    • v.48 no.3
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    • pp.131-143
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    • 2023
  • Background: This study examined the detection limit of thyroid screening monitoring conducted at the time of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 using a Monte Carlo simulation. Materials and Methods: We calculated the detection limit of a NaI(Tl) survey meter to measure 131I accumulation in the thyroid gland of children. Mathematical phantoms of 1- and 5-year-old children were developed in the simulation of the Particle and Heavy Ion Transport code System code. Contamination of the body surface with eight radionuclides found after the FDNPP accident was assumed to have been deposited on the neck and shoulder area. Results and Discussion: The detection limit was calculated as a function of ambient dose rate. In the case of 40 Bq/cm2 contamination on the body surface of the neck, the present simulations showed that residual thyroid radioactivity corresponding to thyroid dose of 100 mSv can be detected within 21 days after intake at the ambient dose rate of 0.2 µSv/hr and within 11 days in the case of 2.0 µSv/hr. When a time constant of 10 seconds was used at the dose rate of 0.2 µSv/hr, the estimated survey meter output error was 5%. Evaluation of the effect of individual differences in the location of the thyroid gland confirmed that the measured value would decrease by approximately 6% for a height difference of ±1 cm and increase by approximately 65% for a depth of 1 cm. Conclusion: In the event of a nuclear disaster, simple measurements carried out using a NaI(Tl) scintillation survey meter remain effective for assessing 131I intake. However, it should be noted that the presence of short-half-life radioactive materials on the body surface affects the detection limit.

Effects of Low Dose ${\gamma}$ Radiation on the Radiosensitivity of Soybean(Glycine max L.) Plant (저선량 ${\gamma}$선 조사가 대두 식물체의 방사선 감수성에 미치는 영향)

  • Kim, Jae-Sung;Chae, Sung-Ki;Back, Myung-Hwa;Kim, Dong-Hee
    • Korean Journal of Environmental Agriculture
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    • v.19 no.4
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    • pp.324-327
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    • 2000
  • Soybean (Glycine max L. cv. Hwangkeum) seeds were irradiated with the dose of $0{\sim}20$ Gy to investigate the effect of the low dose ${\gamma}-ray$ radiation on the early growth and resistance to subsequent high dose of radiation. Germination rate was not enhanced in the seeds irradiated with low dos ${\gamma}-ray$ but plant height and fresh weight increased in the low dose irradiation group. The optimal radiation dose for the growth increasing was 8 Gy in soybean plant. Growth inhibition of soybean plants by high dose radiation was noticeably reduced by pre-irradiation of low dose radiation, Resistance to subsequent high dose of radiation was effective in 8 Gy and 20 Gy irradiation group.

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Dose Effect of Phytosanitary Irradiation on the Postharvest Quality of Cut Flowers

  • Kwon, Song;Kwon, Hye Jin;Ryu, Ju Hyun;Kim, Yu Ri
    • Journal of People, Plants, and Environment
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    • v.23 no.2
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    • pp.171-178
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    • 2020
  • The present study was conducted to determine the effects of electron beam irradiation on the postharvest quality of cut flowers. Cut flowers were irradiated with electron beam at 100, 200, 400, 600, 800, 1,000, and 2,000 Gy with a 10 MeV linear electron beam accelerator to evaluate their irradiation tolerance. Postharvest quality was determined by monitoring fresh weight loss, flower longevity, flower diameter, flowering rate, visual quality of flowers and leaves, and chlorophyll content. Cut flowers showed a radiation-induced damage with increasing the irradiation dose. Flower longevity and fresh weight of cut flowers decreased when the irradiation dose was increased. Flower bud opening was also inhibited in a dose-dependent manner. The effective irradiation doses for 10% reduction of postharvest quality (ED10) values were 144.4, 451.6, and 841.2 Gy in the 'Medusa' lily, 'Montezuma' carnation, and 'Rosina White' eustoma, respectively. Although tolerance of cut flowers to electron beam irradiation vary according to species, cultivars, or maturity stage conditions, it is conceivable that 'Montezuma' carnation and 'Rosina White' eustoma could be tolerated and maintained overall postharvest quality up to 400 Gy, the generic irradiation dose approved by the Animal and Plant Health Inspection Service (APHIS) and the International Plant Protection Convention (IPPC) for postharvest phytosanitary treatments.

Study of Radiation dose Evaluation using Monte Carlo Simulation while Treating Extrahepatic Bile Duct Cancer with High Dose Rate Intraluminal Brachytherapy (간외 담도암 고선량률 관내근접방사선치료 시 몬테카를로 시뮬레이션을 통한 주변장기의 선량평가 연구)

  • Park, Ju-Kyeong;Lee, Seung-Hoon;Cha, Seok-Yong;Lee, Sun-Young
    • The Journal of the Korea Contents Association
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    • v.14 no.2
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    • pp.467-474
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    • 2014
  • The relative dose calculated by MCNPX and the relative dose measured by ionization chamber and solid phantoms evaluated the accuracy comparing with Monte Carlo simulation. In order to apply Monte Carlo simulation the intraluminal brachytherapy of extrahepatic bile duct cancer, 192Ir sealed radioactive source replicate, Bile duct and surrounding organs were made using KMIRD phantom based on a South Korea standard man. To check the absorbed dose of normal organs around bile duct, we set the specific effective energy and initial radioactivity to 1 Ci using MCNPX. Evaluation of the accuracy of the Monte Carlo simulation, the difference of the relative dose is the most 1.96% that satisfy the criteria that is the relative error less than 2% suggested by MCNPX code. In addition, The specific effective energy and absorbed dose of normal organs that were relatively adjacent to bile duct such as right side of kidney, liver, pancreas, transverse colon, spinal cord, stomach and small intestine were relatively high. on the contrary, the organs that were relatively distant to bile duct such as left side of kidney, spleen, ascending colon, descending colon and sigmoid colon were relatively low.

Removal of Chloramphenicol, Salicylic Acid and Ketoprofen using Various Oxidation Processes : Oxidation Kinetic Evaluation (다양한 산화공정을 이용한 수중의 Chloramphenicol, Salicylic Acid 및 Ketoprofen 의약물질 제거 : 산화 동력학 평가)

  • Son, Hee-Jong
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.2
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    • pp.219-226
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    • 2010
  • In order to evaluate a removal characteristic of chloramphenicol, salicylic acid and ketoprofen according to dose of oxidants, $Cl_2$, $O_3$ and $O_3/H_2O_2$ are used as oxidants in this study. In case of that $Cl_2$ is used for oxidizing harmaceuticals, chloramphenicol, salicylic acid and ketoprofen is not removed entirely at $Cl_2$ dose rang of 0.5~5.0 mg/L for 60 min. However, removal tendency of salicylic acid is so obviously at $Cl_2$ dose higher than 1.0 mg/L. In addition, as $Cl_2$ dose and contact time increase, the removal rate of salicylic acid is enhanced. When $O_3$ is used as oxidant, chloramphenicol and ketoprofen is not eliminated at $O_3$ dose range of 0.2~2.0 mg/L. On the contrary, 30~70% of salicylic acid is removed at $O_3$ dose of 1.0~5.0 mg/L. Only 30% removal of salicylic acid is achieved at contact time of 5 min, however, the removal rate is enhanced remarkably at contact time over 10 min. In experiments using $O_3/H_2O_2$ as an oxidant, we can find that $O_3/H_2O_2$ is much more effective than $O_3$ only for removal of 3 pharmaceuticals, and the efficiency is raised according to increase of $H_2O_2$ dose. On reaction rate constant and half-life of 3 pharmaceuticals depending on $Cl_2$, $O_3$ and $O_3/H_2O_2$ dose, experiments using $O_3/H_2O_2$ show that oxidation of pharmaceuticals is less effective as the $H_2O_2/O_3$ ratio increases to above pproximately 1.0 related to reaction rate constant. An oxidation of salicylic acid by $Cl_2$ and $O_3$ particularly has a comparatively high reaction rate constant comparing $O_3/H_2O_2$, and thus salicylic acid is easily eliminated in oxidation processes.

High Dose of FGF-2 Induced Growth Retardation via ERK1/2 De-phosphorylation in Bone Marrow-derived Mesenchymal Stem Cells

  • Shim, Kwang Yong;Saima, Fatema Tuj;Eom, Young Woo
    • Biomedical Science Letters
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    • v.23 no.2
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    • pp.49-56
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    • 2017
  • Fibroblast growth factor (FGF)-2 is one of the most effective growth factors to increase the growth rate of mesenchymal stem cells (MSCs). Previously, we reported that low dose of FGF-2 (1 ng/ml) induced proliferation of bone marrow-derived mesenchymal stem cells (BMSCs) through AKT and ERK activation resulting in reduction of autophagy and senescence, but not at a high dose. In this study, we investigated the effects of high dose FGF-2 (10 ng/ml) on proliferation, autophagy and senescence of BMSCs for long term cultures (i.e., 2 months). FGF-2 increased the growth rate of BMSCs in a dose dependent manner for a short term (3 days), while during long term cultures (2 months), population doubling time was increased and accumulated cell number was lower than control in BMSCs when cultured with 10 ng/ml of FGF-2. 10 ng/ml of FGF-2 induced immediate de-phosphorylation of ERK1/2, expression of LC3-II, and increase of senescence associated ${\beta}$-galactosidase (SA-${\beta}$-Gal, senescence marker) expression. In conclusion, we showed that 10 ng/ml of FGF-2 was inadequate for ex vivo expansion of BMSCs because 10 ng/ml of FGF-2 induced growth retardation via ERK1/2 de-phosphorylation and induction of autophagy and senescence in BMSCs.

The Clinical Usefulness Evaluation of Normal Saline Injection in Coronary Artery Computed Tomography Angiography(Coronary CTA) (관상동맥 전산화단층촬영 조영검사에서 생리식염수 투여를 통한 임상 유용성 평가)

  • Jung, Kang-Kyo;Lee, Mi-Hwa;Cho, Pyong-Kon
    • Journal of radiological science and technology
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    • v.37 no.4
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    • pp.307-313
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    • 2014
  • The purpose of this study is that in coronary artery angiography computed tomography (coronary CTA), to gain high quality of image and to use low dose radiation by administrating normal saline and converting the mode of scanning heart rate (HR) characteristics before infusing contrast media. All patients data (total specimens: 200, male: 108, female: 92) were measured by using appropriate mode of scanning the heart rate (HR) after injection of saline. in addition we measured radiation dose (CTDIvol, effective dose) in all examinations. CT number and noise, and blurring of coronary artery (proximal RCA, middle RCA, proximal LCA) were measured and compared. The result of this study after injection of saline, mean heart rate was decreased about $4.8{\pm}0.3bpm$ (beats per minute). 33 patients (13%) got converting scan mode due to reducing heart rate (HR). In prospective gating mode, radiation dose were measured less $6.0{\pm}1.0mSv$ (54.1%) than retrospective gating mode. Also showed a significant difference in heart rate decrease in image evaluation.

Nonparmetric Method for Identifying Effective and Safe Doses using Placement (유효하고 안전한 용량 결정에 위치를 이용한 비모수적 방법)

  • Kim, Sunhye;Kim, Dongjae
    • The Korean Journal of Applied Statistics
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    • v.27 no.7
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    • pp.1197-1205
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    • 2014
  • Typical clinical dose development studies consist of the comparison of several doses of a drug with a placebo. The primary interest is to find therapeutic window that satisfying both efficacy and safety. In this paper, we propose nonparametric method for identifying effective and safe doses in linear placement using score function. The Monte Carlo simulation is adapted to estimate the power and the family-wise error rate(FWE) of proposed procedure are compared with previous methods.

Methyl Methanesulfonate Stimulated $^3H$-Thymidine Uptake in Synchronized HeLa $S_3$ Suspension Cells Pretreated with Thymidine Analogs

  • Park, Sang-Dai
    • The Korean Journal of Zoology
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    • v.19 no.3
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    • pp.113-122
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    • 1976
  • The rate of $^{3}H$-thymidine uptake induced by MMS in asynchronous HeLa $S_3$ suspension cells was decreased in direct proprotion to dose increase. The combined treatment of BUdR or IUdR with MMS was more effective in reducing the rate of $^{3}H$-thymidine uptake. MMS-stimulated $^{3}H$-thymidine uptake was detected in synchronized $G_2$ stage cells of HeLa $S_3$ suspension cultures following treatment with thymidine double shock. BUdR and IUdR greatly enhanced MMS-stimulated $^{3}H$-thymidine uptake. IUdR was found to be a more effective sensitizer than BUdR in this respect.

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