• Title/Summary/Keyword: S2S Radiation

Search Result 2,859, Processing Time 0.04 seconds

Analysis of solar radiation and simulation of thermal environment in plastic greenhouse - I. Analysis of solar radiation in plastic greenhouse (플라스틱 온실(溫室)의 일사량분석(日射量分析)과 열적환경(熱的環境)의 시뮬레이션에 관(關)한 연구(硏究) - I. 플라스틱 온실(溫室)의 일사량분석(日射量分析))

  • Park, Jae-Bok;Koh, Hak-Kyun
    • Solar Energy
    • /
    • v.6 no.2
    • /
    • pp.22-32
    • /
    • 1986
  • This study was carried out to analyze solar radiation in plastic greenhouse which is covered with polyethylene or polyvinyl chrolide film. A computer model for solar radiation analysis in the plastic greenhouse was developed and solar gain factors for E-W and N-S oriented plastic greenhouse in the greenhouse farming area during winter were investigated. Solar gain factors for E-W plastic greenhouse were 60 to 75 percent which were 10 to 15 percent higher than those for N-S plastic greenhouse from November to January. However, the values were apparently decreased in February and reversed in March, showing 3 to 5 percent higher in E-W plastic greenhouse. About 67 to 72 percent of the total solar radiation was attributed to the south-directed wall and roof for the E-W plastic greenhouse and about 30 percent through walls and 60 percent through roofs for the N-S plastic greenhouse.

  • PDF

The Role of Fas/FasL in Radiation Induced Apoptosis in vivo (방사선에 의한 Apoptosis에서 Fas/Fas L의 역할)

  • Kim, Sung-Hee;Seong, Jin-Sil
    • Radiation Oncology Journal
    • /
    • v.21 no.3
    • /
    • pp.222-226
    • /
    • 2003
  • Purpose: The interaction of the Fas: Fas ligand has been recognized to play an important role in radiation induced apoptosis. The purpose of this study was to investigate the role of Fas and Fas ligand mutations, in radiation-induced apoptosis in vivo. Materials and Methods: Mice with a mutation in the Fas ($C57BL/6J-Fas^{lpr}$) and its normal control (C57BL/6J) and the Fas ligand ($C3H/HeJ-Fas^{gld}$) and its normal control (C3H/HeJ), were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed at various time intervals, and their spleens collected. Tissue sample was stained with hematoxylin-eosin, and the numbers of apoptotic cells scored. The regulating molecules of apoptosis including the p53, Bcl-2, Bax, $Bcl-X_L\;and\;Bcl-X_s$ genes were also analyzed by Western blotting. Results: With 2.5 Gy and 10 Gy of irradiation, the levels of apoptosis were lower in the $C57BL/6J-Fas^{lpr}\;and\;C3H/HeJ-Fas^{gld}$ mice than in the control mice (p<0.05). With the expression of apoptosis regulating molecules, the Bax was increased in both the C57BL/6J and C3H/HeJ mice in response to radiation; the peak levels of Bax in the C57BL6J and C3H/HeJ were 3 and 3.3-fold higher after 8hr, respectively. However the Bax was not increased in either the $C57BL/6J-Fas^{lpr}\;or\;C3H/HeJ-Fas^{gld}$mice. The p53, Bcl-X_L,\;Bcl-X_S$and Bcl-2 showed no significant changes in the $C57BL/6J-Fas^{lpr},\;C3H/HeJ-Fas^{gld}$, C57BL/6J and C3H/HeJ mice. Conclusion: The levels of radiation-induced apoptosis were lower in the lpr and gld, than the control mice, which seemed to be related to the level of Bax activation due to the radiation in the lpr and gld mice. This result suggests that Fas/Fas L plays an important role in radiation-induced apoptosis in vivo.

The Cell Cycle Dependence and Radiation-induced Apoptosis in SCK Mammary Adenocarcinoma Cell Line (SCK선암 세포주에서 방사선에 의한 Apoptosis와 세포 주기)

  • Lee Hyung Sik;Park Hong Kyu;Hur Won Joo;Seo Su Yeong;Lee Sang Hwa;Jung Min Ho;Park Heon Joo;Song Chang Won
    • Radiation Oncology Journal
    • /
    • v.16 no.2
    • /
    • pp.91-98
    • /
    • 1998
  • Purpose : The relationship between environmental PH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. Material and Methods : Mammary adenocarcinoma cells of A/J mice(SCK cells) in exponential growth phase were irradiated with a $l37^Cs$ irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at $37^{\circ}C$ for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Bssults : The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in $G_2/M$ phase rapidly increased to about $70\%$ at 12 h after an exposure to 120y and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in $G_2/M$ increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about $45\%$ at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as $30-35\%$ of the cells were still in the Ga/M phase 48 h after irradiation. The percentage of cells in G1 phase then increased as the Ga/M arrest began to recede. The radiation-induced Ga/M arrest in PH 0.0 medium lasted markedly longer than that in pH 7.5 medium. Conclusion : Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced Ga/M arrest is prolonged in an acidic environment indicating that the suppression of radiation-induced apoptosis and prolongation of radiation-induced Ga/M arrest in an acidic environment are related.

  • PDF

The Public Impression of Radiation as a Product of Science Communication (방사선과 과학커뮤니케이션: 성공과 실패 -북한 핵실험 관련 사례분석-)

  • Kim, Hak-Soo;Oh, Mi-Young;Choi, Jinmyeung;Ha, Hyo-Suk
    • Journal of Radiation Industry
    • /
    • v.2 no.1
    • /
    • pp.35-42
    • /
    • 2008
  • The purpose of this study is to observe how the public impression of radiation is changing over the North Korea's nuclear bomb test. We found that the nuclear bomb test brought more negative impressions of radiation, but, in one year, more positive ones prevailed as in the pre-bomb-test. Those positive impressions were found to be composed of useful and positive elements mostly relative to health care. This suggests that we need to apply radiation (fusion) technology to solving everyday life problems in order to bring more positive impressions of radiation.

Effects of Low Dose Gamma Radiation on the Formation of Shikonin Derivatives on Callus Cultures of Lithospermum erythrorhizon (지치(Lithospermum erythrorhizon S.)의 캘러스배양에서 Shikonin 유도체 생산에 미치는 저선량γ선의 효과)

  • Hwang, Hye-Yeon;Kim, Jae-Sung;Lee, Young-Bok
    • Journal of Plant Biotechnology
    • /
    • v.30 no.3
    • /
    • pp.293-299
    • /
    • 2003
  • The effects of low dosage ${\gamma}$-radiation on the cell growth and the formation of shikonin derivatives were investigated in callus cultures of Lithospermum erythrorhizon under different medium and light conditions. Gamma radiation significantly affected the cell growed and formation of shikonin derivatives, depending on the culture conditions. In the cell cultures grown on M-9 medium, 2Gy and 16Gy of ${\gamma}$-radiation increased the calli growth and the formation of shikonin derivatives, respectively under 16hr day light condition. When calli were cultured for 60 days in the dark after irradiation of ${\gamma}$-radiation, cell growth was increased at low dosage of 1Gy and 2Gy in LS medium containing BA 2mg/L and IAA 0.2mg/L. Interestingly, calli grown in M-9 medium by 2Gy irradiation for 60 days significantly stimulated the formation of shikonin derivatives(13.21mg/g cell fresh wt), which was approximately 6 times higher than untreated cells.

Change in Flavor Patterns of Gamma Irradiated Raw Oyster and Oyster Cooking Drip Determined using an Electric Nose (전자코에 의한 감마선조사 생굴과 굴자숙액의 향기패턴 변화)

  • Han, In-Jun;Park, Jae-Seok;Choi, Jong-Il;Kim, Jae-Hun;Song, Beom-Seok;Yoon, Yo-Han;Byun, Myung-Woo;Chun, Soon-Sil;Lee, Ju-Woon
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.42 no.3
    • /
    • pp.209-214
    • /
    • 2009
  • This study was conducted to evaluate changes in the flavor patterns of gamma irradiated raw oyster and oyster cooking drip using an electronic nose, which consisted of a GC equipped with a surface acoustic wave sensor. The raw oyster was irradiated with 1, 2, 3, 4 and 5 kGy, while the oyster cooking drip was irradiated with 10 and 50 kGy. In the case of raw oyster, the intensities of peaks at retention times (RT) of 2.1 sand 6.8 s were increased, but the peak at a RT of 9.0 s was decreased depending on irradiation dose. In the case of oyster cooking drip, the intensities of peaks at RT 2.5 sand RT 4.1 s increased linearly, but at the peak at RT 5.1 s decreased as the irradiation dose increased. The total amount of flavor components measured in raw oyster increased, while that of oyster cooking drip decreased in response to irradiation.

Study on the Effectiveness of Radiological Technologist's Thyroid Shielding in Pediatric Paranasal Sinus X-ray Examination (어린이 부비동 엑스선 검사에서 검사자의 갑상선 차폐 효과성에 관한 연구)

  • Chang-Kyo Kwak;Jeong-Taek Kwon;Kwang-Je Lee;Il-Hwan Bae;Hye-Jung Kim;So-Mi Lee;Do-Byung Rhee
    • Journal of radiological science and technology
    • /
    • v.47 no.3
    • /
    • pp.197-203
    • /
    • 2024
  • During paranasal sinus X-ray examinations in children, the radiological technologist's thyroid shield is often not implemented to shorten the examination time. This study measured the radiation exposure before and after the implementation of thyroid shielding by analyzing the difference in radiation exposure, the radiological technologist's could receive depending on the actual thyroid shielding. In the left TLD, when thyroid shielding was not performed(N), the radiation exposure dose(mSv) was 2.869 for the depth dose[Hp(10)] and 2.886 for the surface dose[H(3)], and when thyroid shielding was performed(Y), the Hp(10) was 0.033 and the H(3) was 0.034. In the right TLD, when thyroid shielding was not performed(N), the radiation exposure dose was 3.149 for Hp(10) and 3.137 for H(3), and when thyroid shielding was performed, the Hp(10) of (Y) was 0.013 and the H(3) was 0.015. The differences in the overall exposure dose measurement values are all statistically significant (p<0.05). The difference in radiation dose between when thyroid shielding was not performed and when thyroid shielding was performed was more than 99.2% in both cases, indicating a high radiation shielding rate.

Phase II Study on Breast Conservative Surgery Plus Chemo- and Radiotherapy in Treating Chinese Patients with Early Staged Breast Cancer

  • Liu, Yang-Chen;Zhou, Shao-Bing;Gao, Fei;Yin, Xiao-Xiang;Zhao, Ying;Huang, Xin-En
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.6
    • /
    • pp.3747-3750
    • /
    • 2013
  • Purpose: To evaluate the efficacy of conservative surgery plus chemo-, radio-therapy in treating patients with early stage breast cancer. Patients and Methods: Eligible patients were treated by postoperative chemotherapy as well as whole-breast irradiation with tumor bed boost. Postoperative radiotherapy consisted of 6 MV whole breast linear accelerator irradiation with two tangential half fields to a total dose of 45~50 Gy, followed by $10{\sim}15MeV{\beta}$ boost irradiation to tumor bed for 10~20Gy, total dose 56~66Gy. Results: Fifty-two patients were enrolled. Overall 1-, 2- and 3 year survival rates were 98.1%, 92.3%, and 90.4%, respectively, with a local recurrence rate of 5.77%. Cosmetic results were evaluated as good by doctors in 90.4% of patients. Conclusions: Breast conservative surgery combined with chemo- radio-therapy could be a treatment option for Chinese patients with early stage breast cancer.

Fluoroscopic Radiation Exposure during Percutaneous Kyphoplasty

  • Choi, Hyun-Chul
    • Journal of Korean Neurosurgical Society
    • /
    • v.49 no.1
    • /
    • pp.37-42
    • /
    • 2011
  • Objective: The author measured levels of fluoroscopic radiation exposure to the surgeon's body based on the different beam directions during kyphoplasty. Methods: This is an observational study. A series of 84 patients (96 vertebral bodies) were treated with kyphoplasty over one year. The patients were divided into four groups based on the horizontal and vertical directions of the X-Ray beams. We measured radiation exposure with the seven dosimetry badges which were worn by the surgeon in each group (total of 28 badges). Twenty-four procedures were measured in each group. Cumulative dose and dose rates were compared between groups. Results: Fluoroscopic radiation is received by the operator in real-time for approximately 50% (half) of the operation time. Thyroid protectors and lead aprons can block radiation almost completely. The largest dose was received in the chest irrespective of beam directions. The lowest level of radiation were received when X-ray tube was away from the surgeon and beneath the bed (dose rate of head, neck, chest, abdomen and knee: 0.2986, 0.2828, 0.9711, 0.8977, 0.8168 mSv, respectively). The radiation differences between each group were approximately 2.7-10 folds. Conclusion: When fluoroscopic guided-KP is performed, the X-Ray tube should be positioned on the opposite side of the operator and below the table, otherwise the received radiation to the surgeon's body would be 2.7-10 times higher than such condition.

Reconsideration of CN Radiation an d $C_2$ Dissociation Rate Coefficient ($C_2$의 해리 반응 계수와 CN 복사에 대한 재고찰)

  • Hyun, Seong-Yoon;Park, Chul;Chang, Keun-Shik
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.92-95
    • /
    • 2008
  • We performed the theoretical calculation of CN Violet radiation using the code SPRADIAN07 to predict the Lee et al.'s experimental measurements and to reinvestigate $C_2$ dissociation rate. CN Violet radiations are calculated under the Boltzmann and non-Boltzmann distribution using two chemical reaction sets: Park-Losev-G\"{o}kcen-Tsang and Park-Losev-G\"{o}kcen-Tsang-Lee models. Our SPRADIAN07 calculations show improvement in prediction of absolute radiation intensity of CN Violet and its decay rate by Park-Losev-G\"{o}kcen-Tsang reaction set with $C_2$ dissociation rate coefficient of $k_f$ = 1.5${\times}$10$^{16}$ exp(-71,600/$T_x$) cm$^3$ mole$^{-1}$ s$^{-1}$.

  • PDF