• Title/Summary/Keyword: 14-3-${\gamma}$

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Investigation of the Jets of the Blazar 3C 279 with Korean VLBI Network (KVN) 22-129 GHz Observations

  • Yoo, Sungmin;Lee, Sang-Sung;Kim, Sang-Hyun;An, Hongjun
    • Journal of Astronomy and Space Sciences
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    • v.38 no.4
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    • pp.193-202
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    • 2021
  • We present analysis results of Korean VLBI Network (KVN) four-band data for the highly variable blazar 3C 279. We measured the 22, 43, 86, and 129 GHz flux densities and spectral indices of the source using contemporaneous data taken over 5.6 years. We used the discrete correlation function to investigate correlations between the radio emission properties and those measured in the optical (2 × 1014 - 1.5 × 1015 Hz), X-ray (0.3-10 keV), and gamma-ray (0.1-300 GeV) bands. We found a significant correlation between the radio spectral index and gamma-ray flux without a time delay and interpreted the correlation using an extended jet scenario for blazar emission.

A Study on Quality Assurance for Gamma Knife (감마나이프 정도관리에 관한 연구)

  • 서원섭;신동오;지영훈;임영진
    • Progress in Medical Physics
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    • v.14 no.3
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    • pp.184-188
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    • 2003
  • It is strongly recommended that periodic quality assurance should be carried out in the Gamma Knife that is used in radiosurgery since high radiation is delivered in one session. Since the protocols for Gamma Knife recommended by associations or agencies on quality assurance are absent in Korea, hospitals possessing the Gamma Knife have developed their own protocols. In order to develop a quality assurance protocol suitable for Korea, we reviewed the protocols of the Gamma Knife manufacturer, USA and Japan. we categorized the periodic items into three parts,: radiation dose, mechanical and safety part. The USA recommended and regulated more strict than the manufacturer. Japan recommended the items and frequency based on the USA. In conclusion, we tried to suggest a basic Gamma Knife quality assurance protocol suitable for Korea.

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The change on cell wall composition and physiological characteristic of astringent persimmon fruits by gamma irradiation (감마선 처리에 의한 떫은감 과육의 세포벽 성분 및 물성 변화)

  • Kim, Byung-Oh;Cha, Won-Seup;Ahn, Dong-Hyun;Cho, Young-Je
    • Food Science and Preservation
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    • v.22 no.4
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    • pp.512-519
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    • 2015
  • In this study, the effects of gamma-radiation treatment on cell wall composition and physiological characteristics of astringent persimmon fruit were investigated. The soluble tannin contents of gamma-radiated samples were reduced by the radiation treatment. The hardness of the radiated fruit was decreased when compared to non-radiated fruit. Alcohol-insoluble component of the cell wall in the radiated fruit was decreased from 39.3 mg/g to 37.2 mg/g. The water-soluble content of the radiated fruit was increased from 11.4 mg/g to 13.9 mg/g. The cell wall content of the non-radiated fruit was 26.6 mg/g whereas the cell wall content of radiated fruit was decreased to 23.1 mg/g. Due to the maturation of astringent persimmon fruit by gamma-radiation, water-soluble compounds were increased whereas decreasing in cell wall compounds. The contents of lignin, pectin, and cell wall were decreased from 0.82 mg/g and 3.56 mg/g to 0.77 mg/g and 3.14 mg/g, respectively. Acid-soluble hemicellulose content was decreased by gamma-radiation, while alkali-soluble hemicellulose and cellulose contents were increased. Activities of sotening enzyme as polygalacturonase, pectinesterase and $\beta$-galactosidase existed in persimmon fruit were increased by gamma-radiation. In the sensory evaluation, gamma-radition treated persimmon showed very low astringent taste when compared to the non-radiated fruit. In hardness test, the non-radiated persimmon maintained the hardness while gamma-treated persimmon showed softened outer layer due to the condensation of tannin during radiation treatment. Therefore, gamma-radiation treatment will be used for the removal of its astringency of persimmon fruit and for enhancement of its maturation.

Studies on Measuring Volatile Terpenoids in Carrots Using the Direct Headspace Sampling Method (Direct Headspace Sampling 방법을 이용한 당근의 휘발성 Terpenoids 분석에 관한 연구)

  • Park, Yong;Ryu, Jang-Bal;Park, Sang-Gyu;Park, Shin
    • Applied Biological Chemistry
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    • v.40 no.6
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    • pp.536-540
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    • 1997
  • Volatile terpenoids of carrots were measured by the direct headspace sampling method(DHS) with gas chromatography as a study for the breeding of high quality carrots. Using this method, 7 terpenoids such as ${\alpha}-pinene$, ${\beta}-pinene$, ${\beta}-myrcene$, ${\alpha}-terpinene$, limonene, ${\gamma}-terpinene$, and terpinolene were clearly separated. However ${\alpha}-phellandrene$ was not clearly separated from ${\beta}-myrcene$. In addition to this, higher boiling point compounds such as terpinen-4-ol, bornyl acetate, and ${\alpha}-bisbolol$ were not found. The coefficients of $determination(r^2)$ for the 7 terpenoids were higher than 0.99 and the standard curves were highly significant. Four replicated samples using this method demonstrated great reproducibility; the coefficidnt of variation (C.V.) for ${\alpha}-pinene$, ${\beta}-pinene$, ${\beta}-myrcene$, limonene, ${\gamma}-terpinene$, terpinolene, and total terpenoids were 6.8, 6.8, 8.4, 7.1, 3.8, 10.1, 7.1%. Sixty five carrot cultivars breeded worldwide were evaluated for the 7 terpenoids and total terpenoids; the range for ${\alpha}-pinene$, ${\beta}-pinene$, ${\beta}-myrcene$, ${\alpha}-terpinene$, limonene, ${\gamma}-terpinene$, terpinolene, and total terpenoids were $0.28{\sim}2.48\;ppm$, $0.35{\sim}1.87\;ppm$, $0.56{\sim}1.51\;ppm$, 0 ppm, $0.59{\sim}1.84\;ppm$, $0.87{\sim}3.33\;ppm$, $5.15{\sim}35.81\;ppm$, and $9.07{\sim}42.30\;ppm$, respectively. Big differences in each terpenoid and total terpenoids were found among cultivars. On the total terpenoids of the 65 cultivars, 5 cultivars(7.7%) contained less than 10 ppm, 15 cultivars (23.1%) $10{\sim}11.99\;ppm$, 14 cultivars(21.5%) $12{\sim}13.99\;ppm$, 9 cultivars(13.8%) $14{\sim}15.99\;ppm$, 10 cultivars(15.4%) $16{\sim}17.99\;ppm$, 4 cultivars(6.2%) $18{\sim}19.99\;ppm$, 5 cultivars(7.7%) $20{\sim}29.99\;ppm$, and 3 cultivars(4.6%) were higher than 30 ppm. Generally, cultivars developed in Japan contained less total terpenoids than cultivars developed in Europe and America.

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Change in Plasma Vascular Endothelial Growth Factor after Gamma Knife Radiosurgery for Meningioma : A Preliminary Study

  • Park, Seong-Hyun;Hwang, Jeong-Hyun;Hwang, Sung-Kyoo
    • Journal of Korean Neurosurgical Society
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    • v.57 no.2
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    • pp.77-81
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    • 2015
  • Objective : The purpose of this study was to investigate changes in the plasma level of vascular endothelial growth factor (VEGF) after Gamma Knife radiosurgery (GKRS) for the treatment of meningioma. Methods : Fourteen patients with meningiomas had peripheral venous blood collected at the time of GKRS and at 1 week, 1 month, 3 month and 6 month visits. Plasma VEGF levels were measured using commercially available enzyme-linked immunosorbent assay. For controls, peripheral blood samples were obtained from 20 healthy volunteers. Results : The mean plasma VEGF level (29.6 pg/mL) in patients with meningiomas before GKRS was significantly lower than that of the control group (62.4 pg/mL, p=0.019). At 1 week after GKRS, the mean plasma VEGF levels decreased to 23.4 pg/mL, and dropped to 13.9 pg/mL at 1 month, 14.8 pg/mL at 3 months, then increased to 27.7 pg/mL at 6 months. Two patients (14.3%) with peritumoral edema (PTE) showed a level of VEGF 6 months after GKRS higher than their preradiosurgical level. There was no significant association found in an analysis of correlation between PTE and tumor size, marginal dose, age, and sex. Conclusion : Our study is first in demonstrating changes of plasma VEGF after stereotactic radiosurgery (SRS) for meningioma. This study may provide a stimulus for more work related to whether measurement of plasma level has a correlation with tumor response after SRS for meningioma.

Direct Synthesis of Dimethyl Ether from Synthesis Gas (합성가스로부터 디메틸에테르 직접 합성)

  • Hahm, Hyun-Sik;Kim, Song-Hyoung;Kang, Young-Gu;Shin, Ki-Seok;Ahn, Sung-Hwan
    • Journal of the Korean Institute of Gas
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    • v.13 no.4
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    • pp.8-14
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    • 2009
  • Dimethyl ether(DME) was synthesized from synthesis gas by a one-step process in which a hybrid catalyst was used. The hybrid catalyst consisted of Cu-ZnO-$Al_2O_3$ for the methanol synthesis reaction and aluminum phosphate or $H_3PO_4$-modified $\gamma$-alumina for the methanol dehydration reaction. The prepared catalysts were characterized by XRD, BET, SEM, FT-IR and $NH_3$-TPD. From the XRD analysis, it was verified that the aluminum phosphate was successfully synthesized. The specific surface areas of the synthesized aluminum phosphates were varied with the ratio of P/Al. The hybrid catalyst in which P/Al ratio of the aluminum phosphate was 1.2 showed the highest CO conversion of 55% and DME selectivity of 70%. There was no remarkable decrease in catalytic activity with the phosphoric acid treatment of $\gamma$-alumina. However, when treated with concentrated phosphoric acid(85%), the catalytic activity and DME selectivity decreased.

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Effect of Gamma-Irradiation on Trans Fatty Acid, Free Amino Acid and Sensory Evaluation of Dry-fermented Sausage (감마선 조사가 건조-발효소시지의 Trans 지방산, 유리아미노산 및 관능검사 특성에 미치는 영향)

  • Kim, Il-Suk;Yang, Mi-Ra;Jo, Cheorun;Ahn, Dong-Uk;Kang, Suk-Nam
    • Food Science of Animal Resources
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    • v.31 no.4
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    • pp.580-587
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    • 2011
  • In this study, the effects of gamma-irradiation (1, 2 and 4 kGy) on texture profiles, fatty acid composition, free amino acids and sensory evaluation of dry-fermented sausage were evaluated. The hardness and adhesiveness of irradiated samples were significantly lower (p<0.01) than that of the control, while the gumminess of samples irradiated with 2 and 4 kGy was higher than the other tested samples (p<0.01). The sample irradiated at 4 kGy had a higher saturated fatty acid (SFA) content (C14:0, C16:0, C18:0) and significantly lower (p<0.05) unsaturated fatty acid content (UFA) (C16:1, C18:1, C18:3), trans, n-3 and n-6 fatty acid than the non-irradiated sample. Gamma-irradiation resulted in an increase (p<0.05) in phosposerine, aspartic acid and glutamic acid and a decrease (p<0.05) in glutamic acid in free amino acids. For the samples irradiated at 4 kGy, the sulfur odor and fat pungent flavor were significantly higher (p<0.05) and the moldy odor and moldy flavor were significantly lower than the control sample. In conclusion, gamma-irradiation had a significant effect on the texture profiles, fatty acid composition and sensory evaluation of dry-fermented sausage.

Mucosal Immunity Related to FOXP3+ Regulatory T Cells, Th17 Cells and Cytokines in Pediatric Inflammatory Bowel Disease

  • Cho, Jinhee;Kim, Sorina;Yang, Da Hee;Lee, Juyeon;Park, Kyeong Won;Go, Junyong;Hyun, Chang-Lim;Jee, Youngheun;Kang, Ki Soo
    • Journal of Korean Medical Science
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    • v.33 no.52
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    • pp.336.1-336.12
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    • 2018
  • Background: We aimed to investigate mucosal immunity related to forkhead box P3 ($FOXP3^+$) regulatory T (Treg) cells, T helper 17 (Th17) cells and cytokines in pediatric inflammatory bowel disease (IBD). Methods: Mucosal tissues from terminal ileum and colon and serum samples were collected from twelve children with IBD and seven control children. Immunohistochemical staining was done using anti-human FOXP3 and anti-$ROR{\gamma}t$ antibodies. Serum levels of cytokines were analyzed using a multiplex assay covering interleukin $(IL)-1{\beta}$, IL-4, IL-6, IL-10, IL-17A/F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon $(IFN)-{\gamma}$, soluble CD40L, and tumor necrosis factor-${\alpha}$. Results: $FOXP3^+$ Treg cells in the lamina propria (LP) of terminal ileum of patients with Crohn's disease were significantly (P < 0.05) higher than those in the healthy controls. $ROR{\gamma}t^+$ T cells of terminal ileum tended to be higher in Crohn's disease than those in the control. In the multiplex assay, serum concentrations (pg/mL) of IL-4 ($9.6{\pm}1.5$ vs. $12.7{\pm}3.0$), IL-21 ($14.9{\pm}1.5$ vs. $26.4{\pm}9.1$), IL-33 ($14.3{\pm}0.9$ vs. $19.1{\pm}5.3$), and $IFN-{\gamma}$ ($15.2{\pm}5.9$ vs. $50.2{\pm}42.4$) were significantly lower in Crohn's disease than those in the control group. However, serum concentration of IL-6 ($119.1{\pm}79.6$ vs. $52.9{\pm}39.1$) was higher in Crohn's disease than that in the control. Serum concentrations of IL-17A ($64.2{\pm}17.2$ vs. $28.3{\pm}10.0$) and IL-22 ($37.5{\pm}8.8$ vs. $27.2{\pm}3.7$) were significantly higher in ulcerative colitis than those in Crohn's disease. Conclusion: Mucosal immunity analysis showed increased $FOXP3^+$ T reg cells in the LP with Crohn's disease while Th17 cell polarizing and signature cytokines were decreased in the serum samples of Crohn's disease but increased in ulcerative colitis.

Application of RAPD markers for characterization of ${\gamma}$-ray-induced rose mutants and assessment of genetic diversity

  • Chakrabarty, D.;Datta, S.K.
    • Plant Biotechnology Reports
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    • v.4 no.3
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    • pp.237-242
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    • 2010
  • Six parent and their 12 gamma ray-induced somatic flower colour mutants of garden rose were characterized to discriminate the mutants from their respective parents and understanding the genetic diversity using Random amplification of polymorphic DNA (RAPD) markers. Out of 20 primers screened, 14 primers yielded completely identical fragments patterns. The other 7 primers gave highly polymorphic banding patterns among the radiomutants. All the cultivars were identified by using only 7 primers. Moreover, individual mutants were also distinguished by unique RAPD marker bands. Based on the presence or absence of the 48 polymorphic bands, the genetic variations within and among the 18 cultivars were measured. Genetic distance between all 18 cultivars varied from 0.40 to 0.91, as revealed by Jaccard's coefficient matrix. A dendrogram was constructed based on the similarity matrix using the Neighbor Joining Tree method showed three main clusters. The present RAPD analysis can be used not only for estimating genetic diversity present in gamma ray-induced mutants but also for correct identification of mutant/new varieties for their legal protection under plant variety rights.