• Title/Summary/Keyword: Effective Half-life

Search Result 180, Processing Time 0.023 seconds

A Study on the Comparisons of Home Economics Educational Effect between Coeducational Class and One-sex Class of Middle School in a Chungnam Rural Area (충남 일부 농촌 중학교 남녀혼성반과 분리반의 가정교과의 교육 효과 비교 연구 -식생활 단원을 중심으로-)

  • 강경심;김갑영
    • Journal of Korean Home Economics Education Association
    • /
    • v.7 no.2
    • /
    • pp.51-66
    • /
    • 1995
  • The purpose of this thesis is to expound reference data on class management such as class formation and so on by comparing Home Economics Education effect of coeducational class and one-sex class in the coeducational middle school. The major findings were follow: 1. More than half of those teacher who answered choose a coeducational class style as an effective class style(51.7%) because of active class atmosphere, preparation for future home life and getting over fixed sexual ideas by equal curricula content. 2. The results of research for basic knowledge about the Part of Food and Nutritional Science, which was conducted before the class, showed that the score of the one-sex class was higher than that of the coeducational calss(p<0.05) 3. The results of evaluation after class were as follows: The score of one-sex class was higher in the protein food group(p<0.01) and carbohydrate food group(p<0.05). The difference of each class in the calcium food group, the mineral and vitamin food group and the oil and fats food group was very small. The total score of two classes was of little difference.

  • PDF

Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

  • Back, Geum-mun;Park, Sung Ho;Kim, Tae-Hyung
    • Progress in Medical Physics
    • /
    • v.28 no.2
    • /
    • pp.45-48
    • /
    • 2017
  • This paper evaluated the amount of radiation generated by wedge filters during radiation therapy using a high-energy linear accelerator, and the dose to the worker during wedge replacement. After 10-MV photon beam was irradiated with wedge filter, the wedge was removed from the linear accelerator, and the dose rate and energy spectrum were measured. The initial measurement was approximately 1 uSv/h, and the radiation level was reduced to 0.3 uSv/h after 6 min. The effective half-life derived from the dose rate measurement was approximately 3.5 min, and the influence of AI-28 was about 53%. From the energy spectrum measurements, a peak of 1,799 keV was measured for AI-28, while the peak for Co-58 was not measured in the control room. The peaks for Au-106 and Cd-105 were found only measurement was done without wedge removement from the linear accelerator. The additional doses received by the radiation worker during wedge replacement were estimated to be 0.08-0.4 mSv per year.

A Study on Sample manufacturing and Performance Evaluation for Vibration Insulation Material of Noise Barrier for High-Speed Railway (고속철도구간 방음벽 제진재 시험제작 및 성능평가에 관한 연구)

  • Kim Soon-Cheol;Kang Jeong-Ok;Han Kwang-Seob;Jeon Byung-Chan;Han Jong-Moon
    • Proceedings of the KSR Conference
    • /
    • 2005.05a
    • /
    • pp.522-529
    • /
    • 2005
  • The commercial service of KTX from April 1st 2004 has realized that whole country has shrunk into half-day life zone and it opened the times of speed. However, some technical problems unexpected before service have been raised and, among them, the noise generation at train passing was claimed by the residents living nearby the track and it is often publicized by the broadcastings and newspapers. In case where the residential area is close to the track, the installation of noise barrier at trackside is the general measures for noise reduction on bridge section and earthwork section. In case of KTX project, such measures were actually taken without any exception; however, the noise level is still high. In this study, analysis for the reason of higher noise level in spite of which the noise barriers are being installed was carried out, the sample of insulation material effective for noise barrier was manufactured and the performance of the insulation material was evaluated to verify its effectiveness

  • PDF

The Effect of Circadian Rhythm on the Gentamicin Pharmacokinetics in Rabbits (가토에서 생체리듬이 겐타마이신의 약물동태에 미치는 영향)

  • Ko, Jae Won;Baek, Chae Sun;Choi, Jun Shik
    • Korean Journal of Clinical Pharmacy
    • /
    • v.10 no.3
    • /
    • pp.125-129
    • /
    • 2000
  • The effect of circadian rhythm on gentamicin pharmacokinetics was studied in rabbits who took a single intravenous 2 mg/kg dose of gentamicin at 09:00 in the morning (a.m.) and 22:00 in the evening (p.m.). A significant circadian rhythm of pharmacokinetic parameters as a function of time of day was noted in rabbits, showing lower total body clearance $CL_t$ and higher serum area under the curve (AUC) when given in the evening. The half-life $t_{1/2}$ was shorter in the morning $(3.88\pm0.62h)$ when compared to the evening $(4.76\pm0.75\;h)$. The AUC was greater in the evening $(25.92\pm3.49\;{\mu}g/ml{\cdot}hr)$ than that in the morning $(22.42\pm3.42\;{\mu}g/ml{\cdot}hr)$, most likely because the CLt was significantly higher when gentamicin was given in the morning $(0.18\pm0.28\;ml/hr)$ versus in the evening $(0.15\pm0.26\;ml/hr)$. The $t_{1/2}$ of gentamicin in the evening was increased significantly(p<0.05) compared to those of gentamicin in the morning. It is reasonable to consider individual circadian rhythm for effective dosage regimen of gentamicin in clinical chronotherapeutics.

  • PDF

Effective Exhibition Communication of Science: An Analysis of the South Korea's National Science Museum (PEP/IS 모델을 적용한 과학관의 적극적 활용에 관한 연구 : 국립중앙과학관 사례분석과 대안모색)

  • Lee, Eun-A;Kim, Hak-Su
    • Journal of Technology Innovation
    • /
    • v.16 no.2
    • /
    • pp.95-123
    • /
    • 2008
  • As a medium for communication on science and technology, science museum could be important to adults who finished formal school education. By analysing all the exhibits at the National Science Museum and conducting a face-to-face interview survey toward 100 adult visitors, based on the PEP / IS model's perspective(Kim, 2007), this study aimed to find a way to induce many adults to visit science museum from the information consumer's viewpoint, not the information provider's one. The result was that most of the exhibits were not related to problems which people focused attention on. About half of visitors, therefore, did not relate their problems with exhibits and responded that there was no relationship between exhibits and their everyday life. However, they had an idea that science and technology could contribute to solving their problems. These findings could suggest that first, science exhibits in relation to people's focused problems or issues are to be developed, second, programs for parents who are accompanied by their children are to be developed, and last, adults' engagement in planning the science museum exhibits is to be considered.

  • PDF

The Removal of Carbon-14 Scrubber for Removal of Environmental Radioactive Carbon in a Heavy Water Reactor (중수로 환경방출 방사성이산화탄소 제거 장치 개발)

  • 강덕원;지준화;엄희문
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2003.11a
    • /
    • pp.509-513
    • /
    • 2003
  • The radioactive Carbon, C-14, although present in small amount, emits a high energy(up to 0.156MeV) $\beta$ ray and has extremely long half-life(5730years). So special monitoring and management on its generation and discharge is inevitable. A PHWR, due to its own specific designs generates about six times as much C-14 as a PWR does and over 90% of the discharged C-14 comes from the Moderator system and discharged in to the environment through the process of periodic purging of the moderator cover gas system. The present study focussed on the development of effective C-14 scrubber and after production of a test facility and experiments using it, we found that our test facility is very efficient in $CO_2$ removal.

  • PDF

Gynura procumbens Extract Alleviates Postprandial Hyperglycemia in Diabetic Mice

  • Choi, Sung-In;Park, Mi Hwa;Han, Ji-Sook
    • Preventive Nutrition and Food Science
    • /
    • v.21 no.3
    • /
    • pp.181-186
    • /
    • 2016
  • This study was designed to investigate the inhibitory effect of Gynura procumbens extract against carbohydrate digesting enzymes and its ability to ameliorate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. G. procumbens extract showed prominent ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory effects. The half-maximal inhibitory concentration ($IC_{50}$) of G. procumbens extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase was $0.092{\pm}0.018$ and $0.084{\pm}0.027mg/mL$, respectively, suggesting that the ${\alpha}$-amylase inhibition activity of the G. procumbens extract was more effective than that of the positive control, acarbose ($IC_{50}=0.164mg/mL$). The increase in postprandial blood glucose levels was more significantly alleviated in the G. procumbens extract group than in the control group of STZ-induced diabetic mice. Moreover, the area under the curve significantly decreased with G. procumbens extract administration in STZ-induced diabetic mice. These results suggest that G. procumbens extract may help alleviate postprandial hyperglycemia by inhibiting carbohydrate digesting enzymes.

Development of Vancomycin Dosing Nomogram Based on Clinical Pharmacokinetic Data of Korean Adult Patients (한국성인환자의 임상약동학 자료를 이용한 반코마이신 용량설정표 (nomogram)의 개발)

  • 배성미;김상일;강문원;조혜경
    • YAKHAK HOEJI
    • /
    • v.45 no.2
    • /
    • pp.153-160
    • /
    • 2001
  • This research developed an intravenous (IV) vancomycin dosing nomogram based on the clinical pharmacokinetic data of Korean adult patients. Total 99 pairs of steady-state peak and trough serum concentrations of vancomycin were obtained from 73 adult patients in a tertiary general hospital. Serum vancomycin concentrations were determined to assess the appropriateness of initial vancomycin dosing. Only 47.2% of the cases were within therapeutic range. To characterize the clinical pharmacokinetics (PK) of vancomycin, PK parameters including elimination rate constant ( $K_{e}$) half-life( $T_{1}$2/), clearance (C $l_{van}$), volume of distribution ( $V_{d}$) were calculated by using one-compartment, first order pharmacokinetic equations. PK parameters were evaluated based on the differences of patients'renal function and age. Regression analysis showed a significant correlation between C $l_{van}$ and $C_{cr}$ (C $l_{van}$ = -1.89+0.914 $C_{cr}$ , r=0.763) and between $K_{e}$ and $C_{cr}$ , ( $K_{e}$=-0.0037+0.00139 $C_{cr}$ =0.724). The relationship between $K_{e}$ and $C_{cr}$ , and the mean $V_{d}$ were utilized for developing the nomogram to individualize the initial dosing regimen of vancomycin for the patients with various degrees of renal functions. The nomogram may be used as an efficient tool to determine safe and effective doses of vancomycin for the Korean adult patients.nts.nts.nts.s.nts.

  • PDF

A Study on the Synthesis of Oxidized Polyethylene Wax by Controlling Reaction Parameters (공정변수를 조절한 폴리에틸렌 산화왁스 합성에 관한 연구)

  • Yang, Chun-Hoe
    • Journal of the Korean Applied Science and Technology
    • /
    • v.20 no.2
    • /
    • pp.141-147
    • /
    • 2003
  • Oxidized polyethylene wax is obtained by oxidation of polyethylene wax and it is composed of various chemicals, e.g., fatty acid, alcohol, ketone and ester. The application of oxidized polyethylene wax is determined by the composition of these chemical substances. In this basic study we observed the basic reaction parameters of time, temperature, oxygen concentration and catalysts on the oxidation reaction of low molecular weight polyethylene(PE wax) by analyzing the acid value, physical and chemical properties of oxidized PE wax to develop a new oxidation process. Acid values are increased with temperature increase in the rage of $150^{\circ}C^{\sim}180^{\circ}C$ but decreased beyond 190$^{\circ}C$. Acid values are also increased with oxygen concentration. As the oxidation reaction proceeds the molecular weight and softening points of oxidation products are decreased by cracking reaction, but the viscosities are increased. To observe the crystallinity of oxidation products SEM experiment was performed. To obtain a high acid-value product in a mild condition, we adopted free radical catalysts and the acid value of the product using catalyst was higher than the product obtained without catalyst in the same reaction condition. The effective initiators were dicumyl peroxide(DCPO), t-butylperoxy-2-ethyl hexanoate(HOPO) and benzoyl peroxide(BPO) having long half-life.

Drug Interaction Between Verapamil and Pioglitazone Long-term Administered to Rats (흰쥐에서 베라파밀과 장기투여된 피오그리타존과의 약물상호작용)

  • Choi, Dong-Hyun;Kim, Hyun-Yong;Choi, Jun-Shik
    • Korean Journal of Clinical Pharmacy
    • /
    • v.18 no.1
    • /
    • pp.6-10
    • /
    • 2008
  • This study investigated the effect of long-term administration of pioglitazone on the pharmacokinetics of verapamil in rats. Pharmacokinetic parameters of verapamil were determined after oral administration of verapamil (9 mg/kg) in rats coadministered pioglitazone (0.5 mg/kg) or pretreated with pioglitazone (0.5 mg/kg) for 3 and 9 days. Compared to oral control group, the presence of pioglitazone significantly (p<0.05) increased the area under the plasma concentration-time curve (AUC) of verapamil by 48.6% (coad), 61.1% (3 days) and 56.5% (9 days), and the peak concentration($C_{max}$) by 65.1% (coad), 76.8% (3 days) and 66.4% (9 days). The absolute bioavailability (AB%) of verapamil was significantly (p<0.05) higher by 6.2% (coad), 6.7% (3 days), 6.5% (9 days) compared to control (4.2%), and presence of pioglitazone was no significant change in the terminal half-life ($t_{1/2}$) and the time to reach the peak concentration($T_{max}$) of verapamil. Our results indicate that pioglitazone significantly enhanced oral bioavailability of verapamil in rats, implying that presence of pioglitazone could be effective to inhibit the CYP3A4-mediated metabolism of verapamil in the intestine. Drug interactions should be considered in the clinical setting when verapamil is coadministrated with pioglitazone.

  • PDF