• Title/Summary/Keyword: Non-Radiation

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Time-dependent Evolution of Accretion Disk Mass in a Black Hole Microquasar Candidate A0620-00 (블랙홀 마이크로퀘이사 후보 A0620-00의 강착원반 질량의 시간적 진화)

  • Kim, Soon-Wook
    • Journal of the Korean earth science society
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    • v.29 no.7
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    • pp.579-585
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    • 2008
  • The time-dependent evolution of disk mass for outburst limit cycle in a black hole microquasar is calculated based on the non-linear hydrodynamic model of thermally unstable accretion disk. The physical parameters such as black hole mass, disk size and mass transfer rate are adopted to reproduce the historical 1975 outburst observed in a prototype black hole X-ray nova A0620-00. The time-dependent effect of irradiation from the central hot region to the disk is considered in two ways: direct irradiation and indirect irradiation reflected from hot accretion flow above the disk. The accretion disk thermal instability model can account for the bolometric luminosity appropriate to typical characteristics of system luminosity observed in X-ray transients during the whole cycle of the outburst evolution. The maximum mass of the accretion disk, ${\sim}4.03{\times}10^{24}g$, is achieved at the ignition of an outburst, and the minimum value, ${\sim}8.54{\times}10^{23}g$, is reached during the cooling decay to quiescence. The disk mass varies ${\sim}5$ times during outburst limit cycle.

Anti-Ionizing Radiation Effect of Selenium on Osteoporosis Model during Bone Repair Process (골다공증 모델의 뼈 재생기에 있어 셀레늄(Selenium)의 방사선 보호작용)

  • Kim, Hyun;Cho, Sang-Rae;Choe, Changyong;Seong, Hwan-Hoo
    • Journal of Embryo Transfer
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    • v.30 no.3
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    • pp.201-206
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    • 2015
  • Selenium (Se) is an essential trace element for humans and animals, and several findings suggest that dietary Se intake may be necessary for bone health. Accumulating evidence indicates that Se compounds possess anticancer properties. Se is specifically incorporated into proteins in the form of selenocysteine and non-specifically incorporated as selenomethionine in place of methionine. This study evaluated protection by Se in the bone repair process in ovariectomized rats after irradiation. For such purpose, 80 ovariectomized female Sprague-Dawley rats were randomly divided into 4 experimental groups: ovariectomized (Ov), Ov/Se, Ov/irradiated (Irr) and Ov/ Se/Irr. A bone defect was created on the tibia of all animals 40 days after ovariectomy. Two days after surgery, only the Ov/Se and Ov/Se/Irr rats received 0.8 mg Se/kg. Three days after surgery, only the Ov/Irr and Ov/Se/Irr rats received 10 Gy of X-rays on the lower limb region. The animals were euthanized at 7, 15, 22 and 29 days after surgery to assess the repair process, which was evaluated by analysis of trabecular bone number (Masson Trichrome) and birefringence analysis (Picrosirius). It was possible to observe a delay in the bone repair process in the ovariectomized/irradiated group and similarity between the ovariectomized, Ov/ Se and Ov/Se/Irr groups. Our findings suggest that sodium selenite may influence a radioprotective effect in the bone repair of tibia of ovariectomized rats without toxicity.

Estimation of Rice Canopy Leaf Area Index(LAI) by Spectral Reflectance of Solar Radiation in Paddy Field (태양광 반사율을 이용한 벼 군락의 엽면적지수 추정)

  • 이정택;이춘우;주문갑;홍석영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.2
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    • pp.173-181
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    • 1997
  • To estimate the leaf area index(LAI) of rice plant by non-destructive method, spectral reflectance from rice plant canopy was measured by using the spectroradiometer (LI-1800, LICOR Inc.) with one week interval during the rice growing season at Suwon paddy field in 1993. LAI of two medium late maturing varieties, Daechungbyeo and Ilpumbyeo, and one early maturing variety, Jinbubyeo, were observed and compared with those estimated by vegetation index. The reflectance(R) of visible wavelength remained less than 0.1 over entire growing season, but that of near infrared wavelength remained from 0.1 to 0.5 with the significant positive correlation with LAI. Vegetation index determined by the reflectance of visible against near infrared wavelength showed high correlation with LAI of rice canopy. Vegetation index derived from wide band ratio, NIR(720~1, 100nm) /Blue(400~500nm), showed the highest correlation coefficient with LAI. Vegetation index derived from narrow band(10nm interval) ratio, R910/R460, from transplanting to heading stage corresponded well to measured values (Y=0.16799X-0.79776 ; $R^2$=0.94). But another vegetation index, NIR(720~1, 100nm) /Red (600~700nm), showed higher correlation with LAI than NIR /Blue did from heading stage to maturity.

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Effect of Meteorological Condition during Ripening on the Grain Shattering of Rice Plant (등숙기 기상조건이 벼알의 탈립성에 미치는 영향)

  • J. C. Shin;Y. W. Kwon;C. J. Chung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.3
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    • pp.229-234
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    • 1982
  • Environmental factors are known in general to influence much on the development of abscission layer and thereby on shedding of plant parts. The present study was carried out to determine the effect of meterological condition during ripening on the grain shatterability of rice plants at harvest. Different meteorological conditions were obtained by shifting transplanting timing of 40 days old rice seedlings 4 times with a 15 days-interval. Grain shatterability was measured as tensile strength of rice grains: it varied within a range of 214g. to 251g. in a practically non-shattering Japonica variety'Jinheung' and l27.5g. to 204g. in an easy shattering Indica \times Japonica progeny variety'Taeback'. In view of field loss of rice, the variation in tensile strength with time of transplanting and harvest did not matter in Jinheung, but was an important factor in Taeback. In Taeback the tensile strength was significantly correlated positively with mean, maximum and minimum air temperature and relative humidity during a certain period of grain ripening, especially during 30 days period before harvest, but diurnal range of air temperature showed a significant, negative correlation with it. The tensile strength seemed to be more closely related with min. air temperature than max. air temperature, and it was not significantly correlated with radiation amount during any period of pre-harvest. Meteorological effect on grain shatterability may vary with variety, but temperature regime during ripening appears to play major role among the meteorological factors in easy shattering and more thermophilic Indica \times Japonica varieties: lower the temperature, greater the shatterability.

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Bacillus ginsengihumi sp. nov., a Novel Species Isolated from Soil of a Ginseng Field in Pocheon Province, South Korea

  • Ten Leonid N.;Im Wan-Taek;Baek Sang-Hoon;Lee, Jung-Sook;Oh, Hee-Mock;Lee, Sung-Taik
    • Journal of Microbiology and Biotechnology
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    • v.16 no.10
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    • pp.1554-1560
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    • 2006
  • A Gram-positive, aerobic or facultative anaerobic, non motile, endospore-forming bacterial strain, designated Gsoil $114^T$, was isolated from a soil sample of a ginseng field in Pocheon Province (South Korea), and was characterized taxonomically by using a polyphasic approach. It grew well on nutrient agar medium and utilized a limited number of organic substrates as sole carbon sources, including D-xylose and some other carbohydrates, but did not utilize L-amino acids and organic acids. The isolate was positive for oxidase test but negative for catalase, and negative for degradation of macromolecules such as starch, cellulose, xylan, casein, chitin, and DNA. The G+C content of the genomic DNA was 41.8 mol%. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major fatty acids were $anteiso-C_{15:0}$ (32.1%), $iso-C_{15:0}$ (30.5%), and $anteiso-C_{17:0}$ (30.2%). Comparative 16S rRNA gene sequence analysis showed that strain Gsoil $114^T$ fell within the radiation of the cluster comprising Bacillus species and joined Bacillus shackletonii LMG $18435^T$ with a bootstrap value of 95%. The highest 16S rRNA gene sequence similarities were found with Bacillus shackletonii LMG $18435^T$ (97.6%), Bacillus acidicola DSM $14745^T$ (96.9%), Bacillus sporothermodurans DSM $10599^T$ (96.5%), and Bacillus oleronius DSM $9356^T$ (96.5%). The phylogenetic distance from any other validly described species within the genus Bacillus was less than 96%. DNA-DNA hybridization experiments showed that the DNA-similarities between strain Gsoil $114^T$ and closest phylogenetic neighbors were less than 39%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil $114^T$ (=KCTC $13944^T$=DSMZ $18134^T$) was classified in the genus Bacillus as the type strain of a novel species, for which the name Bacillus ginsengihumi sp. nov. is proposed.

Analysis of Intrafractional Mass Variabilities Using Deformable Image Registration Program (영상변조 프로그램을 이용한 호흡 위상 간 종양의 움직임 특성 분석)

  • Cho, Jeong-Hee;Kim, Joo-Hoo;Seo, Sun-Youl;Han, Dong-Kyoon
    • Journal of radiological science and technology
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    • v.35 no.2
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    • pp.173-181
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    • 2012
  • The aim of this study is to compare the geometric characteristics of the lung tumor, such as tumor centroid, HU change relative to breath phase, depending on tumor location and adhesion using 4DCT and deformable image registration program (MIMVista). The Y axis change was most significant and the mean Y axis centroid fluctuation was $7.32{\pm}6.88mm$ in lower lung tumor. The mean HU variation in lower lung mass has changed more than other locations, and its mean HU variation was $7.7{\pm}4.97%$ and non-adhered mass was more changed. Correlation for the mass volume between 3DCT and MIP was very high and its coefficient was 0.998. The effect of tumor location, adhesion and diaphragm excursion to geometric uncertainties was analyzed by linear regression model, it was influenced to mass deformation and geometrical variation so much except diaphragm excursion. but intra-fractional and inter-patient's uncertainties were great, so it couldn't find any exact deformation trend.

The Development of Classification System of Medical Procedures in Korea (한국표준의료행위 분류체계 개발)

  • Park, Hyoung-Wook;Sohn, Myong-Sei;Kim, Han-Joong;Park, Eun-Cheol;Yu, Seung-Hum
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.4 s.55
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    • pp.877-897
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    • 1996
  • In recent years, the Korean Medical Association has undertaken the feat of establishing the Korean Standard Terminology of Medical Procedures with the dedicated help of 32 medical academic societies. However, because the project is being conducted by several different circles, it has yet to see a clear system of classification. This thesis, therefore, proposes the three principles of scientific properties, usefulness and ideology as the basis for classification system and has developed the Classification System of Medical Procedures in Korea upon their foundation. The methodology and organization of this thesis as follows. First, by adopting scientific classification system of Feinstein(1988), an analysis of the classification systems of the medical procedures in the United States, Japan, Taiwan, WHO was carried out to reveal the framework and the basic principles in each system. Second, the direction of classification system has been constructed by applying the normative principle of medical field in order to show the future direction of the medical field and realize its ideology. Third, a finalized framework for the classification system will be presented as based on the direction of classification system. Of the three basis principles mentioned above, the analysis on the principles of usefulness was left out of this thesis due to the difficulty of establishing specific standards of analysis. The results of the study are as follows. The overall structure of the thesis is aimed at showing the 'Prevention-Therapy-Rehabilitation' quality of comprehensive health care and consists of six chapters; I. Prevention and Health Promotion II. Evaluation and Management III. Diagnostic Procedures IV. Endoscopy V. Therapeutic Procedures VI. Rehabilitation Chapter three Diagnostic Procedures is divided into four parts : Functional Diagnosis, Visual Diagnosis, Pathological Diagnosis, Biopsy and Sampling. Chapter five Therapeutic Procedures is divided into Psychiatry, Non-Invasive Therapy, Invasive Therapy, Anaesthesia and Radiation Oncology. Of these sub-divisions, Functional Diagnosis, Biopsy and Sampling, Endoscopy and Invasive Therapy employs the anatomical system of classification. On the other hand, Visual Diagnosis, Pathological Diagnosis, Anesthesia and Diagnostic Radiology, namely those divisions in which there is little or no overlapping in services with other divisions, used the classification system of its own division. The classification system introduced in this thesis can be further supplemented through the use of the cluster analysis by incorporating the advice and assistance of other specialists.

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Evaluation of the Postoperative Motor Function for Metastatic Brain Tumors Around the Motor Cortex (운동중추 주변에 위치한 전이성 뇌종양의 수술 후 운동 기능에 대한 평가)

  • Kim, Sang Hyo;Jung, Shin;Kang, Sam Suk;Lee, Jung Kil;Kim, Tae Sun;Kim, Jae Hyoo;Kim, Soo Han;Lee, Je Hyuk
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup1
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    • pp.25-29
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    • 2001
  • Objective : Intracranial metastasis is responsible for nearly 50% of mortalities of systemic cancers. Although its frequency is increasing and there is little doubt that improving the quality and expectancy of life is the final goal, the mode of treatment is still disputed. The authors report the postoperative motor function after surgery in patients with metastatic tumors around the motor cortex. Materials and Methods : We studied 24 patients with metastatic tumors around the central sulcus during the last 22 months. Motor function was assessed pre- and post-operatively as well as its response to corticosteroids. MRI, neuronavigation system and intraoperative ultrasonography were used for tumor localization and functional MRI and cortical stimulator were used to define the motor cortex. Results : Single metastasis was found in 13 cases(54%) and 11 cases(44%) had multiple foci. Thirteen cases were located in precentral, 7 in postcentral, and 4 in superior or middle-frontal lobe. The most common primary focus was the lung(16 cases). There was no difference in postoperative motor function improvement between the steroid responsive group and non-responsive group(92% versus 90%). Ninty-two percent of the patients showed significant improvement of motor function and lived independently but there was worsening in the upper extremity in one and in another no improvement. Whole brain radiation of 3000cGy was given in all cases and 4 patients died of recurrence in primary or intracranial focus during mean follow-up periods of 14 monthes. Conclusion : Surgery may provide substantial improvement of the motor function and quality of life of the patients with metastatic tumors around the motor cortex.

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Effects of Shield Materials on the Growth and Yield Characteristics of Melon Grown inside a Plastic Greenhouse in Summer Season (고온기 멜론 시설재배 시 자재별 차광 효과)

  • Lee, Jae Han;Lee, Jung Sup;Kwon, Joon Kook;Yeo, Kyung Hwan;Bang, Ji Woong;Kim, Jin Hyun;Lee, Choung Keun;Park, Kyoung Sub;Myung, Dong Ju
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.304-311
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    • 2021
  • This Experiment was conducted to determine the effects of light shield materials when melon grown inside a plastic greenhouse in summer season. The average temperatures were 36.6℃, 34.5℃ and 34.0℃ respectively for the control(non-shield), coating agent, and the white net. The light transmittances were 69% and 75%, respectively inside the greenhouse treated with the coating agent and white net immediately after applicants, compared with that inside the control greenhouse. At the 40 and 80 days after treatment, the light transmittances for the coating agent were 92% and 98%, respectively, indicating it was slowly decomposed and removed, but there was no change in the transmittance for the white net. While the leaf number did not differ among the treatments, the plant height was higher in the white net and shading agent than in control. The weight of the leaves, fresh-weight and dry-weight were no different from that of shading, but it became heavier in the later stages. The marketable fruit yield was increased by 6% for white nets and 5% for the coating agent compared to control, there was no statistical significance. Therefore, coating agent is considered as an effective method to lower temperature during high temperature period, but it is preferable to use it in consideration of cultivation period, because the coating agent is gradually removed.

A Study on the Distribution of Microorganisms in Department of Radiography (영상의학과 촬영실의 미생물 분포에 관한 연구)

  • Chang, Jeong-Hyun;Yang, Eun-Ju;Kim, Young-Jae
    • Journal of the Korean Society of Radiology
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    • v.15 no.2
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    • pp.165-171
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    • 2021
  • To prevent the secondary hospital-acquired infection (cross-infection) from occurring in the general radiographic room in the department of radiology, the microbial measurement was conducted at the points making direct close contact with radiologists and patients. For the case of radiologists, the microbial measurement and incubation were focused on the x-ray tube handle of the radiation generating device, and, for the case of patients, the microbial measurement and incubation were focused on the chin supporting device, chest-contact point, and handle. Once disinfected with Aniosurf, the sterilized media were gathered and identified, and the microorganisms were confirmed. Based on the identification results, it was confirmed that the points making direct close contact with radiologists showed a value of 103 CFU for Proteus mirabilis, Staphylococcus epidermidis, Bacillus spp. and Candida spp., and that the points making direct close contact with patients showed a value of 103~5 CFU for Proteus mirabilis, Enterococcu faecium, Pseudomonas aeruginosa, NTM(Non-Tuberculosis Mycobacteria) and Candida spp.. It was also confirmed that the types and number of microorganisms gathered from the points making direct close contact with patients were greater. Fortunately, most of the involved microorganisms were observed to be on the skin surface and are known to become extinct when disinfected in accordance with the hospital-acquired infection control rules. However, since even minor exposure to such microorganisms may be lethal for patients with reduced immunity, caution must be taken. In particular, since the points making contact with patients showed a high level of microbial measurement, it was thought that it would be necessary for radiologists and personnel having frequent access to strictly disinfect the parts, such as instruments and handles, making frequent contact with patients. The purpose of this study was to announce the importance of safe microbial control in the radiographic inspection room in hospital, and this study is expected to be used as the baseline data for preventing hospital-acquired secondary infection and Nth infectious diseases.