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Managing Technological Risk and Risk Conflict : Public Debates on Health Risks of Mobile Phones EMF (기술위험 관리와 위험갈등 : 휴대전화 전자파의 인체유해성 논란)

  • Jung, Byung-Kul
    • Journal of Science and Technology Studies
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    • v.8 no.1
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    • pp.97-129
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    • 2008
  • We are living in the time of high probability of technological risk due to increased rate of technology development and diffusion of new technologies. Resolving uncertainties, the basic attribution of risk, by accumulating knowledge over the risk factors of certain technology is critical to management of technological risk. In many cases of technological risks, high uncertainty of knowledge is commonly mentioned reason for public controversies on risk management. However, the type of technological risk with low social agreement and low uncertainty of knowledge, the main reason for public controversy is absence of social agreement. Public debates on the risks of mobile phones electromagnetic fields(EMF) to human health comes under this category. The knowledge uncertainty on human health effect of mobile phones EMF has been lowered increasingly by accumulating enormous volume of knowledge though scientists have not reached a final conclusion whether it pose a risk to the physical and mental health of the general population or not. In contrast with civil organizations calling for precautionary approach based regulation, the mobile phone industry is cling to the position of no-regulation-needed by arguing no clear evidence to prove health risks of mobile phone EMF has found. In Korea, government set exposure standards based on a measurement called the 'specific absorption rate'(SAR) and require the mobile phone industry to open SAR information to the public by their own decision. From the view of pro-regulation side based on precautionary approach, technology risk managament of mobile phones EMF in Korea is highly limited and formalized one with limited measuring of SAR on head part only and problematic self-regulated opening of information about SAR to the public. As far as the government keeps having priority on protecting interest of mobile phone industry over precautionary regulation of mobile phones EMF, the disagreement between civil organizations and the government will not resolved. The risk of mobile phones EMF to human health have high probability of being underestimated in the rate and damage of risk than objectively estimated ones due to familiarity of mobile phone technology. And this can be the cause of destructive social dispute or devastating disaster. To prevent such disastrous results, technology risk management, which integrating the goals of safety with economic growth in public policy and designing and promoting risk communication, is required.

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Detection of Brain Metastatses Using Limited Brain MR Imaging : Usefulness of Limited Contrast-Enhanced MR Imaging in Brain Metastasis (뇌전이암 진단을 위한 제한적 뇌 자기공명영상의 유용성에 관한 연구)

  • Kwon, Sun Jung;Lee, Yun Sun;An, Jin Yong;Park, Hee Sun;Jung, Sung Soo;Kim, Ju Ock;Kim, Jin Hwan;Song, Chang Joon;Kim, Sun Young
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.499-505
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    • 2003
  • Background : The brain is a common site of a metastasis in lung cancer patients. If left untreated, the patients succumb to progressive neurological deterioration with a lower survival rate than with other metastases sites. Contrast-enhanced MR imaging in the absence of symptoms or clinical signs is not recommended for identifying a cerebral metastasis in lung cancer patients because of management effectiveness. This pilot study was performed to estimate whether or not limited brain MR imaging, which has a lower cost, could be used to replace conventional brain MR imaging. Method : Between April 1999 and March 2001, 43 patients with a primary lung cancer and the others (breast cancer, stomach cancer, colon cancer, malignant melanoma etc), who had neurological symptoms and signs, were examined using conventional brain MR imaging to examine brain metastases. The control group involved four patients who had no evidence of brain metastases the sensitivity, specificity and correlation of limited brain MR imaging were compared with conventional brain MR imaging. Results : All the 43 patients who were examined with conventional brain MR imaging showed evidence of brain metastases, whereas limited brain MR imaging indicated that 42 patients had brain metastases(sensitivity=97.67%). One patient in whom limited brain MR imaging showed no brain metastasis had a metastasis in the cerebellum, as shown by the contrast-enhanced T1 weighted axial view using conventional brain MR imaging. The conventional brain MR imaging and the limited brain MI imaging of the 4 control patients both indicated no brain metastases (specificity=100 %). The Pearson Correlation of the two groups was 0.884(Confidence Interval : 99%) observed. Conclusion : Limited brain MR imaging can detect a brain metastasis with the same accuracy. In addition, it is cost-effective (229,000 won, 180$) compared to conventional brain MR imaging(529,000 won, 480$) when patients had neurological symptoms and signs or staging.

Tuberculin Survey to Estimate the Prevalence of Tuberculosis Infection of the Elementary Schoolchildren under High BCG Vaccination Coverage (고 비시지 접종률 상태에서 초등학생들의 투베르쿨린 조사를 통한 감염률 추정 조사)

  • Kim, Hee Jin;Oh, Soo Yeon;Lee, Jin Bum;Park, Yun Sung;Lew, Woo Jin
    • Tuberculosis and Respiratory Diseases
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    • v.65 no.4
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    • pp.269-276
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    • 2008
  • Background: Although the prevalence of tuberculosis infections (PTBI) is one of the basic epidemiologic indices, no survey has been carried out since 1995 because the nation-wide tuberculosis prevalence survey was changed to a surveillance system. Subjects without a BCG scar are examined in a tuberculin survey. However, it is very difficult to select these subjects under high vaccination coverage. It is important to evaluate the impact of BCG vaccinations on the tuberculin response and estimate the PTBI regardless of the BCG vaccination status. Methods: A nation-wide, school-based cross-sectional tuberculin survey was carried out among first graders in elementary school in 2006. A total of 5,148 children in 40 schools were selected by quota sampling. Tuberculin testing with 0.1 ml of two tuberculin units of PPD RT23 was carried out on 4,018 children. The maximum transverse diameter of induration was measured 48 to 72 hours later. The presence of a BCG scar was checked separately. Results: There were no BCG scars in 6.3% of the subjects. The mean induration size of tuberculin testing was $3.7{\pm}4.4mm$, which included 1,882 (46.8%) subjects with an induration size of 0 mm. The PTBI was 10.9% (439 subjects) using a cut-off point of ${\geq}10mm$ (conventional method). The annual risk of tuberculosis infections (ARTI) was 1.9% when the mean age of the subjects was assumed to be 6 years. There was no difference in the PTBI according to the presence or absence of a BCG scar [11.2% vs 7.6% (OR: 1.54, 95% CI: 0.98~2.43)]. Using a mirror image technique with 16 mm as the cut-off point, the PTBI and ARTI had decreased to 2.4% and 0.4% respectively. Conclusion: PTBI and ARTI, as estimated by conventional methods, appear to be high among BCG vaccinated children. A mirror image technique is more suitable for estimating the indices in a country with an intermediate burden of tuberculosis than the conventional method.

3-D Conformal Radiotherapy for CNS Using CT Simulation (입체조준장치를 이용한 중추신경계의 방사선 입체조형치료 계획)

  • 추성실;조광환;이창걸
    • Progress in Medical Physics
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    • v.14 no.2
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    • pp.90-98
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    • 2003
  • Purpose : A new virtual simulation technique for craniospinal irradiation (CSI) that uses a CT-simulator was developed to improve the accuracy of field and shielding placement as well as patient positioning. Materials and Methods : A CT simulator (CT-SIM) and a 3-D conformal radiation treatment planning system (3D-CRT) were used to develop CSI. The head and neck were immobilized with a thermoplastic mask while the rest of the body was immobilized with a Vac-Loc. A volumetric image was then obtained with the CT simulator. In order to improve the reproducibility of the setup, datum lines and points were marked on the head and body. Virtual fluoroscopy was performed with the removal of visual obstacles, such as the treatment table or immobilization devices. After virtual simulation, the treatment isocenters of each field were marked on the body and on the immobilization devices at the conventional simulation room. Each treatment fields was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR) and digitally composited radiography (DCR) images from virtual simulation. Port verification films from the first treatment were also compared with the DRR/DCR images for geometric verification. Results : We successfully performed virtual simulations on 11 CSI patients by CT-SIM. It took less than 20 minutes to affix the immobilization devices and to obtain the volumetric images of the entire body. In the absence of the patient, virtual simulation of all fields took 20 min. The DRRs were in agreement with simulation films to within 5 mm. This not only reducee inconveniences to the patients, but also eliminated position-shift variables attendant during the long conventional simulation process. In addition, by obtaining CT volumetric image, critical organs, such as the eyes and the spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. Differences between the DRRs and the portal films were less than 3 m in the vertebral contour. Conclusion : Our analysis showed that CT simulation of craniospinal fields was accurate. In addition, CT simulation reduced the duration of the patient's immobility. During the planning process. This technique can improve accuracy in field placement and shielding by using three-dimensional CT-aided localization of critical and target structures. Overall, it has improved staff efficiency and resource utilization by standard protocol for craniospinal irradiation.

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Taxonomy of the infraspecific taxa of Adonis amurensis Regel et Radde (Ranunculaceae) (복수초(미나리아재비과)의 종내분류군에 대한 분류)

  • Son, Dong Chan;Ko, Sung -Chul
    • Korean Journal of Plant Taxonomy
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    • v.41 no.2
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    • pp.144-155
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    • 2011
  • The infraspecific taxa of Adonis amurensis Regel et Radde are currently known to include one subspecies (subsp. nanus Y. Lee), two varieties (var. ramosa Makino, and var. dissectipetalis Y. Lee) and two forms (for. argentatus Y. Lee, and for. viridescensicalyx Y. Lee). Among them, the remaining three taxa except for subsp. nanus and var. dissectipetalis are unified with A. amurensis. Therefore, we examined the morphological characteristics and geographical distribution of A. amurensis in effort to elucidate the taxonomic status of subsp. nanus and var. dissectipetalis. After the subsp. nanus samples had been transplanted from their type locality, i.e. highland at more than 1,000 m above sea level, to a lowland habitat, we measured the samples' morphological characteristics. The range of values we recorded of the plant height and floral diameter from the subsp. nanus samples were within the parameters used to characterize A. amurensis. Accordingly, subsp. nanus has been characterized as an ecophene of A. amurensis. It is considered as a synonym of A. amurensis. Among the populations of A. amurensis (sensu Y.Lee, author), those with highly dissected petals at their apices have previously been described as var. dissectipetalis. However, this characteristic has been observed together with obtuse or rounded petal apices not only in one population but also in a single individual. However, populations with these characteristics belong to A. pseudoamurensis due to the simultaneous development of leaves and flowers, branched stems, acute leaf apices, and petals that are shorter than sepals. Therefore, we suggest that A. amurensis var. dissectipetalis be unified with A. pseudoamurensis. Very useful characteristics for distinguishing A. amurensis from its relative species are anthesis, the presence or absence of branches, the development of scales into normal leaves, the relative length of the sepals and petals, and the position of the stipules. A. amurensis is geographically restricted to E. Asia, including E. Siberia, and especially on the Korean Peninsula, it is distributed throughout the northern provinces of Gyeonggi province and in Gangwon province, Gyeongbuk province (Mt. Bohyeon-san) and Jeonbuk province (Mt Jeoksang-san) along Baekdudaegan mountain.

A Study on the Oral Health Behavior of High School Students in Jeolla-bukdo (전북지역 일부 고등학생의 구강보건형태에 관한 연구)

  • Yu, Mi-Sun;Goo, Kyong-Mi;Kim, Jeong-Suk
    • Journal of dental hygiene science
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    • v.9 no.2
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    • pp.225-230
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    • 2009
  • This study executed questionnaire 388 high school boy students in Jeolla-bukdo Namwon from June 9, 2008 to 20th prepares basic data about boy student's oral health behavior, and examines closely the connection factor and plans oral health promotion. Questionnaire distributed getting classroom teacher's cooperation and reclaimed through classroom teacher after make questionnaire by students. The collected data executed Chi-square test and descriptive statistics using SPSS program and the result is as following. 1. Response that responded that students of 61.1% are 2 times in toothbrushing number of times on 1 day, and appeared by thing which 69.1% does toothbrushing most much after way in the morning, and cleans up and down by toothbrushing method was the most by 36.6%. A student of only 8.5% was using auxiliary oral hygiene devices. 2. The oral medical examination and treatment engine use experience rate was 93.6%, and students of 82.9% do treatment as reason by last oral medical examination and treatment use purpose and did coming to help. The 1 year within use experience rate was 47.7%, and students of 77.1% were satisfied for medical examination and treatment. 3. Toothbrushing frequency of smoked students appeared low compared to students woo do not smoke, and students, who do drinking, was expose toothbrushing number by 3 limes compared to students who do not. 4. The activity limitation experience rate by oral disease was 16.0%, and the year absence experience rate was 5.2%, and the studies achievement hindrance experience rate appeared by 13. 1%. As a result, is considered to strengthen on-time oral medical examination and oral health education, and need prevention and policy of early treatment putting first.

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Experimental Model of Cardiac Xenograft, Mouse Heart to Rat. (이종이형의 심장이식의 실험적 모델)

  • Kim, Byung-Il;Sohn, Sang-Tae;Shin, Sung-Ho;Chung, Won-Sang;Kim, Hyuk;Kim, Young-Hak;Kang, Jung-Ho;Jee, Heng-Ok;Lee, Chul-Burm;Seo, Jung-Kuk
    • Journal of Chest Surgery
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    • v.32 no.1
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    • pp.1-4
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    • 1999
  • Background: The transplantation of organs between phylogenetically disparate or harmonious species has invariably failed due to the occurrence of hyperacute rejection or accerelated acute rejection. But, concordant cardiac xenograft offer us an opportunity to study xenotransplantation in the absence of hyperacute rejection. Current therapeutics for the prolongation of survival of rodent concordant xenotransplantation are not ideal with many regimens having a high mortality rate. Cyclosporine A & Mycophenolate Mofetil are new immunosuppresive agent which has been shown to be effective at prolonging survival of allograft, as purine synthesis inhibitor. Material and Method: We used white mongrel rats as recipient and mice as donor, divided 4 groups(n=6), control group(Group 1) has no medication or pretreatment, Group 2 has splenectomy as pretreatment 7∼10 days before transplantation, Group 3 has Cyclosporine A treatment group, Group 4 has combined treatment of Cyclosporine A & Mycophenolate Mofetil(RS 61443). We compared survival time. Reuslt: We can't find significant difference of survival time between each groups. Conclusion: We concluded that rejection of cardiac xenograft was different from rejection of allograft, and new immunossuppresive Agent(Mycophenolate Mofetil, Cyclosporine A) was not effective for prolongation of survival time after cardiac xenograft.

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Anti-inflammatory effect of Polygonum multiflorum extraction in activated RAW 264.7 cells with lipopolysaccharide (Lipopolysaccharide로 활성화된 RAW 264.7 세포에서 적하수오(Polygonum multiflorum) 추출물의 항염증 효과 검증)

  • Lee, Eunsu;Kim, Hyeongjeong;Yu, Jae-Myo;Cho, Yong-Hun;Kim, Dong-In;Shin, Yuhyeon;Cho, Yeongje;Kwon, O-Jun;An, Bongjeon
    • Food Science and Preservation
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    • v.21 no.5
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    • pp.740-746
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    • 2014
  • The anti-inflammatory effects of Polygonum multiflorum water extracts (PMWs) and Polygonum multiflorum 70 % ethanol extracts(PMEs) were investigated using lipopolysaccharide-induce by inflammatory response. The inhibitory effects of PMWs and PMEs on the production of nitric oxide (NO) and pro - inflammatory cytokines in LPS - activated Raw 264.7 cells were investigated. The effects were examined after reducing production of Nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein levels. RAW 264.7 cells were cultured with LPS ($1{\mu}g/mL$) in the presence or absence of PMWs and PMEs for 24 h to determine their NO, iNOS, COX-2 levels. During the entire experimental period 10, 25, 50 and $100{\mu}g/mL$ of PMWs and PMEs showed no cytotoxicity. At these concentrations, PMWs and PMEs concentration dependently reduced the production of nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-$1{\beta}$ (IL-$1{\beta}$). PMWs and PMEs were inhibited the activittion of iNOS, COX-2 by 89%, 54%, 91% and 57% respectively, at $100{\mu}g/mL$. These results indicate that PMWs and PMEs significantly reduces the effect of oxidative and inflammatory cytokines.

Diversity, Saccharification Capacity, and Toxigenicity Analyses of Fungal Isolates in Nuruk (누룩곰팡이 분리균의 다양성 및 당화능 분석과 독소생산능 조사)

  • Kim, Min Sik;Kim, Sinil;Ha, Byeong-Seok;Park, Hye-Young;BaeK, Seong-Yeol;Yeo, Soo-Hwan;Ro, Hyeon-Su
    • The Korean Journal of Mycology
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    • v.42 no.3
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    • pp.191-200
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    • 2014
  • Nuruk samples collected from various regions in Korea were investigated in terms of fungal contents and diversity. In measurement of colony forming unit (CFU) in Nuruk suspensions on DRBC agar, Nuruk samples MS4, MS8, and MS10 were among the highest fungal density, with $1,278.9{\pm}21.6$ (${\times}10^4$), $1,868.0{\pm}27.7$ (${\times}10^4$), and $775.1{\pm}19.2$ (${\times}10^4$) were among the samples showing the highest fungal density. CFU per 20 mg Nuruk, respectively. The majority of fungal components were yeasts, including Pichia anomala, P. kudriavzevii, Kluyveromyces marxianus, and Saccharomycopsis fibuligera, whereas Aspergillus oryzae and Rhizopus oryzae, the representative Nuruk fungi, were predominant only in the low fungal density Nuruks (MS2, MS5, and MS11). Saccharification capability of the fungal isolates was assessed by measurement of amylase activity in the culture broth. The highest amylase activity was found in A. niger and A. luchuensis, followed by S. fibuligera. A. oryzae and R. oryzae showed fair amylase activity but significantly lower than those of the three fungal species. R. oryzae was suggested to play an additional role in degradation of ${\beta}$-glucan in crop component of Nuruk since R. oryzae was the only fungus that showed ${\beta}$-glucanase activity among the fungal isolates. To confirm the safety of Nuruk, aflatoxigenicity of the isolated Aspergillus was estimated using the DNA markers norB-cypA, aflR, and omtA. All of the isolates turned out to be non-aflatoxigenic as evidenced by the deletion of gene markers, norB-cypA and aflR, and the absence of aflatoxin in the culture supernatants shown by TLC analysis.

The Formation and Significance of Korean Ceramics Collections in Modern Britain (근대 영국의 한국도자 컬렉션의 형성 과정과 그 의미)

  • Kim, Yunjeong
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.104-123
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    • 2019
  • Various European countries were active rather early on in the formation and research of Korean ceramics, which are considered a representative genre of Korean art. Of these, England is especially noteworthy due to its relatively large volume of extant archival material related to the procurement of Korean ceramics in modern Britain. The material is important in that it contributes to our understanding of the formation and economic worth of these collections. Especially meaningful are the previously unknown documents dating to the period when institutions such as the British Museum and the Victoria & Albert Museum were most actively collecting Korean ceramics. These documents provide insight into the circumstances-process, prices, standards, perceptions, etc.-of procurement for the Korean ceramics now in British collections. The changes in the perception of Korean ceramics and the intention for forming such collections in modern Britain can be divided into three periods. The first, starting from the late 1870s and ending in the late 1880s, is categorized by the collectors' misguided ideal of Korean ceramics in the absence of a true understanding of the subject. During the late 1880s up until 1910, the Korean ceramics entering British collections were mostly ethnographic in nature and examples of implements used in Koreans' daily lives. Lastly, from 1910 to 1940, Korean ceramics were regarded as art objects to be collected, and Goryeo celadons formed the core of many of the British collections being assembled at the time. As for the matter of collecting standards and processes, the matter is examined through the study of three individuals who visited Korea and acquired Korean ceramics in the early 20th century. After 1910, the British started to make trips to the Far East via boat or the Trans-Siberian Express and purchase Korean ceramics during their travels. It has been confirmed that former bureaucrats were able to acquire 'good and old Goryeo ceramics' at reasonable prices from either tomb robbers or through direct visits to regions where such wares were being excavated. In addition, this study also focuses on the previously unfamiliar company Kavanaugh & Co, which made important sales and provided transport of various objects, including Korean ceramics, to its Western clients. The final part of this study examines the standards of appraisal for the Korean ceramics collected in modern Britain. The main criterion the balance between form and price of the piece. In other words, the best pieces were those that were of superior quality but acquired at the cheapest prices. British collectors particularly valued not only the Goryeo celadons favored by the Japanese but also Joseon ceramics for their innovative form, design, and technique. These standards of aesthetic and form were important factors that influenced the formation of diverse Korean ceramic collections in modern Britain.