• Title/Summary/Keyword: low-dose

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The Dielectric Properties due to the Temperature and Applied Voltage of Oriented Polypropylene Film Irradiated by $^{60}/Co-${\gamma}$$ ($^{60}/Co-${\gamma}$$선으로 조사된 이축연신 폴리프로필렌 필림의 온도 및 전압에 따른 유전특성)

  • 홍진웅;이수원;김왕곤
    • Journal of the Korean Society of Safety
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    • v.9 no.1
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    • pp.48-55
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    • 1994
  • In this paper, It is studied that the variation of the dielectric absorption of the specimen according to the change with $^{60}$ Co-${\gamma}$ ray irradiation dose of the influence of temperature and applied voltage. In order to investigate the effect of irradiated oriented polypropylene film, we have observed dielectric properties within the temporature range of 30~130 ($^{\circ}C$) and voltage range of 100~250 (V). As for the dependency of temperature by tan $\delta$, the $\alpha$ peak which appears at high temperature increases accordingly to the increment of irradiation dose which is contributed by the crystal region and moves towards the high temperature. The $\beta$ peak which appears the orientation by dipoles and molecular motions in the amorphous region at low temperature. For the dependency of voltage by tan $\delta$ at low temperature, the peak of the tan $\delta$ shifts accordingly to the increment of irradiation dose towards the high temperature region.

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The Effect of the Electron Beam with a Low Dose on the Dielectric Characteristics of Transformer Oils (II) (변압기유의 유전특성에 미치는 저조사량 전자선의 영향 (II))

  • Lee, Yong-Woo;Cho, Don-Chan;Shin, Jong-Yeol;Kim, Wang-Kon;Hong, Jin-Woong
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1559-1561
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    • 1996
  • In this experiment, it is decided to irradiated with a low dose of electron beam. Such that being things, the specimen is produced by the different dose, for example, 0.5[Mrad], 1[Mrad], 2[Mrad] except for original specimen. From the result of the analysis for the physical properties using FT-IR spectrum, it is confirmed that carbonyl groups of irradiated specimen is increased more than that of non-irradiated specimen. And all of nitric compound are disappeared by irradiating with electron beam. From the result of the dielectric characteristics, the specimen irradiated with 2[Mrad] is excellent.

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Effects of Fish Oil Supplementation to Korean Lactasting Women -II. The Effects on Lipid Content and Fatty Acid Composition of Breast Milk- (한국인 수유부에 어유의 보충 급여 효과에 관한 연구 - II. 모유의 지질 농도 및 지방산 조성에 미친 영향-)

  • 임현숙
    • Journal of Nutrition and Health
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    • v.29 no.2
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    • pp.188-191
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    • 1996
  • This study was undertaken to determine the effects of fish oil supplementation with low dose on the lipid content and fatty acid composition of breast milk. Among 18 lactating women who were exclusively breast-fed their babies, 6 were in control group and 12 were in fish lil groups. The subjects in fish oil groups were supplemented with 1.96g/d or 3.92g/d of fish oil for 2 weeks from 10 to 12 weeks of postpartum. All subjects consumed their usual diet at home. Breast milk samples were collected at the final day of experiment. By fish oil supplementation, the concentrations of triglyceride, cholesterol, free fatty acid and phospholipid as well as total lipid in breast milk tended to increase, but not significant. There was no dose-dependent response. The fatty acid composition of breast milk was not changed by fish oil supplementation. These results suggest that low dose of fish oil supplementation may increase of lipid content, but does not affect on the fatty acid composition of breast milk.

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The Characteristics of Volume Resistivity for the Transformer Oil irradiated with the Electron Beam of Low Dose (저조사량 전자선에 대한 변압기유의 체적고유저항 특성)

  • 이용우;이우영;조돈찬;김왕곤;홍진웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.211-215
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    • 1996
  • In this paper, the volume resistivity of transformer oil is made researches so that the electrical properties for transformer oil is investigated. The specimen is produced by the irradiation of electron beam classified into the low dose, such as 0.5[Mrad], 1[Mrad], 2[Mrad]. The effect of electron team irradiation is studied by investigating the electrical properties of dielectric liquid due to the difference of electron beam dose. To measure the physical properties of transformer oil, courier Transform-Infrared Spectroscopy is investigated. And the study far the electrical properties is made by measuring the volume resistivity of each specimen. By means of the result from this experiments, it is introduced that the movement of carrier to contribute to the volume resistivity on the electrical properties.

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Electrical Properties of Transformer Oils due to Electron Beam Irradiation (전자선 조사에 따른 변압기유의 전기적 특성)

  • 이용우;조돈찬;홍진웅
    • Electrical & Electronic Materials
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    • v.10 no.8
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    • pp.756-762
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    • 1997
  • In this paper the change of electrical properties of transformer oil due to electron beam irradiation is investigated. The specimens are produced with a some different dose of 0.5[Mrad], 1[Mrad] and 2[Mard] except for original specimen. The physical properties of each specimen is analyzed by using the FT-IR spectrum. So it is confirmed that carbonyl groups are increased according to the increase of electron beam dose and also that the nitric compounds are disappeared. The magnitude of dielectric dissipation factor appears maximum value by the contribution of dipoles and ions in the low temperature low voltage region and it is stable due to the saturation of carriers in the high temperature high voltage region in the electric conduction characteristics. Volume resistivity is also measured one of original specimen is larger than irradiated specimen.

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Antidiabetic Activity of Formular containing an Euonymus alata and Mori Foluim in Multiple Low Dose Streptozotocin-induced Rats

  • Chung, Sung-Hyun;Lee, Sung-Hyun;Kim, Hee-Ja
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.97.1-97.1
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    • 2003
  • Antidiabetic activity of formular containing an Euonymus alata (EA) and Mori Foluim (MF) was investigated in oral glucose tolerance test (OGTT) and multiple low dose Streptozotocin (MLDSTZ)-induced rats. Optimum ratio between EA and MF was found to be 1:1 in OGTT, and two strengths (250 and 500 mg/kg for each medicinal plant) were coadministered with 20 mg/kg of STZ in 5 consecutive days. At 3rd week, water and food intakes were compared between groups and polydipsia and polyphagia shown in diabetic control were markedly improved in dose dependent manner. (omitted)

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Evaluation of the Low Tube Voltage in the Computed Tomography Scan Technique using a Low Concentration Contrast Agent (저농도 조영제를 사용한 CT검사에서 저관전압 기법에 따른 유용성 평가)

  • Jung, Kang-Kyo;Cho, Pyong-Kon
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.71-79
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    • 2016
  • The purpose of this study is computed tomography contrast agent at low concentrations and low tube voltage technique to evaluate the usefulness on the phantom image. By varying the degree of mixture by the contrast medium concentration it was inserted in phantom. It was taken by changing the tube voltage and tube current step by step, and to evaluate the dose and the CT value obtained from the phantom image. As a result, low-contrast, low tube voltage(300 mgI/ml, 100 kV) was reduced by an average 21%(CTDIvol; computed tomography dose indexvol) more standard condition(350 mgI/ml, 120 kV). SNR was increased at all depths of the phantom, respectively 1:10 and 1:20(by diluting a contrast agent and normal saline) 12.2(26%) 6.2(17%). CNR was increased at all depths of the phantom, respectively 1:10 and 1:20(by diluting a contrast agent and normal saline) 11.5(32%), 6.3(26%). Research work on the CT scan is necessary in a variety of studies on the low contrast concentration and low tube voltage techniques for dose reduction and reducing of side effects the contrast agent.

Evaluation of the Lens Absorbed Dose of MVCT and kV-CBCT Use for IMRT to the Nasopharyngeal Cancer Patient (비인두암 환자에 대한 세기조절 방사선치료 시 이용되는 MVCT와 kV-CBCT의 수정체 흡수선량 평가)

  • Choi, Jae Won;Kim, Cheol Chong;Park, Su Yeon;Song, Ki Weon
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.2
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    • pp.131-136
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    • 2013
  • Purpose: Quantitative comparative evaluation of the difference in eye lens absorbed dose when measured by MVCT and kV-CBCT, though such a dose was not included in the original IMRT treatment plan for the nasopharyngeal cancer patient. Materials and Methods: We used CT (Lightspeed Ultra 16, General Electric, USA) against an Anderson rando phantom (Alderson Research Laboratories Inc, USA) and established the plan for tomotherapy treatment (Tomotherapy, Inc, USA) and linear accelerator treatment (Pinnacle 8.0, Philips Medicle System) for the achieved CT images on the same condition with the nasopharyngeal cancer patient treatment plan. Then, align the ther-moluminescence dosimeter (TLD100 Harshaw, USA) with the eye lens, shot the lens with Tomotherapy MVCT under 3 conditions (Fine, Normal, and Coarse), and shot both lenses with kV-CBCT under 2 conditions (Low Dose Head and Standard Dose Head) 3 times each. Results: When we analyzed the eye lens absorbed dose according to MVCT and kV-CBCT images by using both Tomotherapy and Pinacle 8.0, we achieved the following result; According to Tomotherapy MVCT, RT 0.8257 cGy in the Coarse mode, LT 0.8137 cGy, RT 1.089 cGy and LT 1.188 cGy in the Normal mode, and RT 2.154 cGy and LT 2.082 cGy in the Fine mode. According to Pinacle 8.0 kV-CBCT, RT 0.2875 cGy and LT 0.1676 cGy in the Standard Dose mode and RT 0.1648 cGy and LT 0.1212 cGy in the Low-Dose mode. In short, the MVCT result was significantly different from that of kV-CBCT, up to 20 times. Conclusion: We think kV-CBCT is more effective for reducing the amount of radiation which a patient is receiving during intensity modulated radiation treatment for other purposes than treatment than MVCT, when we consider the absorbed dose only from the viewpoint of image-guided radiation therapy. Besides, we understood the amount of radiation is too sensitive to the shooting condition, even when we use the same equipment.

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Controversies about Radioactive Iodine-131 Remnant Ablation in Low Risk Thyroid Cancers: Are We Near A Consensus?

  • Zaman, Maseeh Uz;Fatima, Nosheen;Padhy, Ajit Kumar;Zaman, Unaiza
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6209-6213
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    • 2013
  • Well differentiated thyroid cancers (WDTC), including papillary (80%) and follicular (10%) types, are the most common endocrine cancers globally. Over the last few decades most the diagnosed cases have fallen into low risk categories. Radioactive iodine-131 (RAI) has an established role in reducing recurrence and improving the survival in high risk patients. In patients with primary tumor size <1 cm, RAI is not recommended by many thyroid societies. However, low risk WDTC has been an arena of major controversies, most importantly the role and dose of adjuvant RAI for remnant ablation to minimize chances of recurrence and improving survival. This review is an attempt to update readers about the previous and existing practice based on results of non-randomized trials and evolving trends fueled by recently published randomized studies.

Effects of Cyclosporin A, FK506, and 3-Deazaadenosine on Acute Graft-versus-host Disease and Survival in Allogeneic Murine Hematopoietic Stem Cell Transplantation (마우스 동종 조혈모세포 이식모델에서 Cyclosporin A, FK506, 3-Deazaadenosine 등의 약제가 급성 이식편대 숙주병과 생존에 미치는 영향)

  • Jin, Jong Youl;Jeong, Dae Chul;Eom, Hyeon Seok;Chung, Nak Gyun;Park, Soo Jeong;Choi, Byung Ock;Min, Woo Sung;Kim, Hack Ki;Kim, Chun Choo;Han, Chi Wha
    • IMMUNE NETWORK
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    • v.3 no.2
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    • pp.150-155
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    • 2003
  • Background: We investigated the effect of donor marrow T cell depletion, administration of FK506, cyclosporin A (CSA), and 3-deazaadenosine (DZA) on graft versus host disease (GVHD) after allogeneic murine hematopoietic stem cell transplantation (HSCT). Methods: We used 4 to 6 week old Balb/c ($H-2^d$, recipient), and C3H/He ($H-2^k$, donor) mice. Total body irradiated recipients received $1{\times}10^7$ bone marrow cells (BM) and $0.5{\times}10^7$ splenocytes of donor under FK506 (36 mg/kg/day), CSA (5 mg/kg/day, 20 mg/kg/day), and DZA (45 mg/kg/day), which were injected intraperitoneally from day 1 to day 14 daily and then three times a week for another 2 weeks. To prevent the GVHD, irradiated Balb/c mice were transplanted with $1{\times}10^7$ rotor-off (R/O) cells of donor BM. The severity of GVHD was assessed daily by clinical scoring method. Results: All experimental groups were well grafted after HSCT. Mice in experimental group showed higher GVHD score and more rapid progression of GVHD than the mice with R/O cells (R/O group) (p<0.01). There were relatively low GVHD scores and slow progressions in FK506 and low dose CSAgroups than high dose CSA group (p<0.01). The survival was better in FK506 group than low dose CSA group. All mice treated with CSA died within 12 days after HSCT. The GVHD score in DZA group was low and slow in comparison with control group (p<0.05), but severity and progression were similar with low dose CSA group (p=0.11). All mice without immunosuppressive treatment died within 8 days, but all survived in R/O group (p<0.01). Survival in low dose CSA group was longer than in control group (p<0.05), but in high dose CSA group, survival was similar to control group. The survival benefit in DZA group was similar with low dose CSA group. FK506 group has the best survival benefit than other groups (p<0.01), comparable with R/O group (p=0.18), although probability of survival was 60%. Conclusion: We developed lethal GVHD model after allogeneic murine HSCT. In this model, immunosuppressive agents showed survival benefits in prevention of GVHD. DZA showed similar survival benefits to low dose CSA. We propose that DZA can be used as a new immunosuppressive agent to prevent GVHD after allogeneic HSCT.