• Title/Summary/Keyword: Human Exposure

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Effect of High Tube Voltage and Scatter Ray Post-processing Software on Image Quality and Radiation Dose During Chest Anteroposterior Radiography (흉부 전·후방향 검사 시 고관전압 및 산란선 후처리 소프트웨어 적용이 화질과 선량에 미치는 영향)

  • Kim, Jong-Seok;Joo, Young-Cheol;Lee, Seung-Keun
    • Journal of radiological science and technology
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    • v.44 no.4
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    • pp.295-300
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    • 2021
  • This study aims to present new chest AP examination exposure conditions through a study on the effect on image quality and patient dose by applying high tube voltage and scatter ray post-processing software during chest AP examination in digital radiography equipment. This study was used a human body phantom and in the chest AP position, the dosimeter was placed horizontally at the thoracic spine 6. The experiment was conducted by dividing into a low tube voltage (70 kVp, 400 mA, 3.2 mAs) group and a high tube voltage (100 kVp, 400 mA, 1.2 mAs) group. The collimation size (14″× 17″) and the source to image receptor distance(110 cm) were same applied to both groups. Radiation dose was presented to dose area product and entrance surface dose. Image quality was compared and analyzed by comparing the difference between the signal-to-noise ratio and the contrast-to-noise ratio of the image according to the application of the scatter ray post-processing software under each condition. The average value of the entrance surface dose in the low and high tube voltage conditions was 93.04±0.45 µGy and 94.25±1.51 µGy, which was slightly higher in the high tube voltage condition, but the dose area product was 0.97±0.04 µGy and 0.93±0.01 µGy. There was a statistically significant difference in the group mean value(p<0.01). In terms of image quality, the values of the signal-to-noise ratio and the contrast noise ratio were higher in the high tube voltage than in the low tube voltage, and decreased when the scattering line post-processing function was used, but the contrast resolution was improved. If there is a scatter ray post-processing function during chest AP examination, it is helpful to actively utilize it to improve the image quality. However, when this function is not available, I thought that applying a higher tube voltage state than a low tube voltage state will help to realize images with a large amount of information without changing the dose.

Molecular Mechanisms Involved in Peptidoglycan-induced Expression of Tumor Necrosis Factor-α in Monocytic Cells (펩티도글리칸에 의한 단핵세포의 Tumor necrosis factor-α 발현 기전 연구)

  • Jeong, Ji-Young;Son, Yonghae;Kim, Bo-Young;Kim, Koanhoi
    • Journal of Life Science
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    • v.29 no.11
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    • pp.1251-1257
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    • 2019
  • Peptidoglycan (PG) is found in atheromatous lesions of arteries, where monocytes/macrophages express inflammatory cytokines, including tumor necrosis factor-alpha ($TNF-{\alpha}$). This study investigated the effects of PG on $TNF-{\alpha}$ expression and examined possible cellular factors involved in $TNF-{\alpha}$ upregulation. The overall aim was to identify the molecular mechanisms underlying inflammatory responses to bacterial pathogen-associated molecular patterns in the artery. Exposure of human THP-1 monocytic cells to PG enhanced the secretion of $TNF-{\alpha}$ and induced its gene transcription. Inhibition of TLR-2/4 with OxPAPC significantly inhibited $TNF-{\alpha}$ gene expression, whereas inhibition of LPS by polymyxin B did not. The PG-induced expression of $TNF-{\alpha}$ was also significantly suppressed by pharmacological inhibitors that modulate activities of cellular signaling molecules; for example, U0126 (an ERK inhibitor), SB202190 (a p38 MAPK inhibitor), and SP6001250 (a JNK inhibitor) significantly attenuated PG-induced transcription of $TNF-{\alpha}$ and secretion of its gene product. $TNF-{\alpha}$ expression was also inhibited by rapamycin (an mTOR inhibitor), LY294002 (a PI3K inhibitor), and Akt inhibitor IV (an Akt inhibitor). ROS-regulating compounds, like NAC and DPI, also significantly attenuated $TNF{\alpha}$ expression induced by PG. These results suggest that PG induces $TNF-{\alpha}$ expression in monocytes/macrophages by multiple molecules, including TLR-2, PI3K, Akt, mTOR, MAPKs, and ROS.

Analysis of Minimum Detectable Activity Concentration of Water Samples and Evaluation of Effective Dose (물 시료의 최소검출가능 농도 분석과 유효선량 평가)

  • Jang, Eun-sung;Kim, Yang-su;Lee, Sun-young;Kim, Jung-Soo
    • Journal of the Korean Society of Radiology
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    • v.14 no.7
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    • pp.857-862
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    • 2020
  • In March 2011, a tsunami off Japan caused radioactive material that had seeped into the sea from the Fukushima nuclear accident to flow to the Pacific Ocean, causing pollution to sea life. For a comparative evaluation with the area surrounding the site of a nuclear power plant by the release of radioactive materials, an area 20 to 30 km away from the emergency protection plan area was selected as a comparative point considering weather conditions, population distribution, etc. In addition, the government intends to analyze the minimum detection radiation received by residents around the nuclear power plant and evaluate the effective dose. Analysis of tritium radiation from water samples showed that most of the samples were not detected and that 0.0014 % to 0.777 % of the annual legal standard of 1 mSv for the general public had little effect on the human body. Therefore, the measurement and analysis of water samples around the nuclear power plant site is expected to help relieve anxiety, such as exposure to the general public and neighboring residents due to radiation release.

A Study on the Risk of Halogen Lamp for Pigsty Heating and Fire Prevention (축사 난방용 할로겐램프의 위험성 및 화재 예방에 관한 연구)

  • Lee, Jae kyung;Seo, Seong Hyeon;Lee, Jae Wook
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.3
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    • pp.553-564
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    • 2021
  • This study analyzed the the risk of halogen lamp for pigsty heating and its fire prevention. Halogen lamps are used for keeping warm in pen because of their excellent economy and convenience. However, there is a high risk of fire due to poor safety management and exposure to animal movements. In fact, after exploring old pigsty and cattle shed, it was easy to confirm that they were exposed to fire risks. We noted this point and studied the possibility of fire by experiment due to combustible contact with halogen lamp and carelessness in use. The experiment was conducted under conditions similar to the actual use environment. After installing halogen lamps to the height used in actual pen, the temperature change was observed with infrared camera with straw, sawdust and rice husks on the floor. And assuming abnormal conditions, the experiment was also conducted under conditions the lamp dropped on the floor or combustible material came into contact with the glass tube inside the lamp. If halogen lamps were used in normal condition, there was no risk of fire. However, in abnormal use environments, smoke comes out or even ignited. Even if it is convenient for use or highly utilized, high risk of fire will require setting up fire prevention measures or regulation of use. Through in-depth fire investigation and research, we should promote the risk of fire and make efforts to prevent fire to minimize human life and property damage.

Development of integrated disaster mapping method (II) : disaster mapping with risk analysis (통합 재해지도 작성 기법 개발(II) : 리스크 분석을 적용한 재해지도 작성)

  • Park, Jun Hyung;Kim, Byunghyun
    • Journal of Korea Water Resources Association
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    • v.55 no.1
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    • pp.85-97
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    • 2022
  • In this study, a method for an integrated flood risk mapping was proposed that simultaneously considers the flood inundation map indicating the degree of risk and the disaster vulnerability index. This method creates a new disaster map that can be used in actual situations by providing various and specific information on a single map. In order to consider the human, social and economic factors in the disaster map, the study area was divided into exposure, vulnerability, responsiveness, and recovery factors. Then, 7 indicators for each factor were extracted using the GIS tool. The data extracted by each indicator was classified into grades 1 to 5, and the data was selected as a disaster vulnerability index and used for integrated risk mapping by factor. The risk map for each factor, which overlaps the flood inundatoin map and the disaster vulnerability index factor, was used to establish an evacuation plan by considering regional conditions including population, assets, and buildings. In addition, an integrated risk analysis method that considers risks while converting to a single vulnerability through standardization of the disaster vulnerability index was proposed. This is expected to contribute to the establishment of preparedness, response and recovery plans for providing detailed and diverse information that simultaneously considers the flood risk including social, humanistic, and economic factors.

Effects of Endocrine Disrupting Chemicals on the Nervous System (내분비계 교란물질이 신경계에 미치는 영향)

  • Shin, Hyun Seung;Wi, Jae Ho;Lee, Seung Hyun;Choi, Soo Min;Jung, Eui-Man
    • Journal of Life Science
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    • v.32 no.1
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    • pp.70-77
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    • 2022
  • Endocrine disrupting chemicals (EDCs) have been attracting significant attention in modern society, owing to the increased incidence rate of various diseases along with population growth. EDCs are found in many commercial products, including some plastic bottles and containers, detergents, liners of metal food cans, flame retardants, food, toys, cosmetics, and pesticides. EDCs have a hormonal effect on the human body, which disrupts the endocrine system, notably affecting sexual differentiation and normal reproduction, and can trigger cancer as well. Recently, the association between neurological diseases and EDCs has become a hot topic of research in the field of neuroscience. Considering that EDCs negatively affect not only neuronal proliferation and neurotransmission but also the formation of the neuronal networks, EDCs may induce neurodevelopmental disorders, such as autism spectrum disorders and attention-deficit/hyperactivity disorder as well as neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. In light of these potentially deleterious outcomes, important efforts have been underway to minimize the exposure to EDCs through appropriate regulations and policies around the world, but chemicals that have not yet been associated with endocrine disrupting properties are still in wide use. Therefore, more epidemiological investigations and research are needed to fully understand the effects of EDCs on the nervous system.

In vitro Anti-oxidant and Anti-inflammatory Effects of Moringa Folium and Eucommiae Cortex 2:1 (g/g) Mixed Formula (모링가:두충 2:1 (g:g) 복합 조성물의 in vitro 항산화 및 항염 효능 연구)

  • Heo, Seok-Mo;Yang, Jin-Won;Kim, Jong-Lae;Park, Mi-Ryeong;Kim, Tae Gi;Ku, Sae-Kwang;Park, Soo-Jin
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.36 no.4
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    • pp.125-129
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    • 2022
  • The purpose of study is to evaluate in vitro anti-oxidant and anti-inflammatory effects of Moringa Folium and Eucommiae Cortex 2:1 (g/g) mixtures (MEMix). HaCaT and human normal dermal fibroblast were treated with 0.01-1 mg/mL of MEMix to monitor cytotoxicity. Radical scavenging activities of MEMix were examined by DPPH assay. To explore anti-inflammatory effect, Raw 264.7 cells were pretreated with MEMix for 1h and subsequently exposed to LPS for 18h. NO release and cytotoxicity of Raw 264.7 cells were measured by adding Griess and MTT reagents, respectively. TNF-α, IL-1β, IL-6, and PGE2 productions were examined by ELISA. Immunoblot analysis was conducted to examine COX-2 expression in MEMix pretreated Raw 264.7 cells. Up to 1 mg/mL concentration, treatment of MEMix for 24 h did not affect normal dermal fibroblast viability and significantly reduced cell viability of HaCaT cells with no concentration dependency. MEMix increased DPPH radical scavenging activity with concentration dependency. Radical scavenging activities by 1 mg/mL of MEMix was comparable with 30 µM of trolox. Pretreatment of MEMix did not change the reduction of Raw 264.7 cell viability. Exposure of LPS in Raw 264.7 cells significantly increased NO, TNF-α, IL-1β, IL-6, and PGE2 productions, and MEMix pretreatment attenuated these productions by LPS concentration dependently. However, pretreatment with MEMix did not change COX-2 expression by LPS in Raw 264.7 cells. MEMix showed in vitro anti-oxidant and anti-inflammatory activities. MEMix would be useful candidate agent against inflammation.

A Study on the Distribution and Reduction Method of Indoor Radon Concentration in Daejeon Metropolitan City (대전광역시 주택 실내 라돈 농도 분포와 저감 공법 적용 연구)

  • Jang, Yong-Chul;Yang, Jae Hwan;Kim, Hongkyoung;Lee, Gain;Song, Hakyun;Kim, Byeonghwan;Kwon, Youngsun
    • Journal of Environmental Impact Assessment
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    • v.31 no.5
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    • pp.286-295
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    • 2022
  • In this study, the concentration distribution of indoor radon in Daejeon Metropolitan City was investigated and the reduction efficiency was evaluated by applying the radon reduction methods. Based on the results of the National Institute of Environmental Research, indoor radon measurements were conducted on 24 selected houses, and the average value of District A was 261 Bq/m3, far exceeding the standard, and even in the same house, indoor radon concentration was affected by measurement point and time. In the case of eight houses that applied the soil venting method to reduce radon, the indoorradon level was significantly lowerthan the standard value, and the average reduction efficiency was also around 55%, indicating a good reduction effect. In addition, the average reduction efficiency was around 90% in the two houses that carried out the shielding method, showing the very excellent effect of the indoorradon reduction. Even if the same reduction method is applied when reducing radon, the reduction efficiency may vary depending on various factors such as the structure of the building, the frequency of ventilation, and the season, so it is necessary to accurately evaluate the effectiveness of the reduction method in the future. Based on this, it is necessary to establish indoor radon management measures in Daejeon Metropolitan City to reduce human harm caused by radon exposure.

The Effect on Attention of College Students by Epidermal Cooling in Posterior and Lateral of Upper Cervix (경추부 후면 및 측면 피부 냉각 작용이 대학생의 주의력에 미치는 영향)

  • Chang, Ji Hong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.15 no.5
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    • pp.328-334
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    • 2022
  • The process that one may consciously focuses on necessary stimulation among tremendous amount of stimulation through human sensory systems is called attention in psychology. It is known that the attention can be affected by many factors such as room temperatures, humidity level, etc. In the field of sports science, ice packs are widely used for recovery from exercise fatigue providing fast heat transfer by conduction. However, the effect on attention by so-called iced-pack-cooling has not been tested. This research focuses on the attention levels when one is provided with a special cooling pad on their dorsal and lateral cervices. 40 subjects were divided into four groups and their attention level was evaluated based on the exposure conditions of combinations in reading and light walking with and without the cooling pad. The Frankfruter Aufmerksamkeits-Inventar, FAIR was used to evaluate the attention levels; the performance index, quality index, and continuity index consist of the FAIR test indicating the selectiveness of the attention, correctness of the attention, and maintaining term of the attention, respectively. Analysis of variance was carried out for those variables and post-hoc if applicable. When visual attention is constantly used for reading and studying, application of conductive heat transfer by the cooling pads is significantly helpful for improvement in selectiveness of the attention and maintaining terms of the attention levels. Also, light walking yielded improvement in selectiveness of the attention and maintaining terms of the attention levels; however one should presupposedly consider the loss of reading time.

Association Between Nut Consumption and Hypertension According to Sleep Duration Among Korean Adults (Aged 19-69 Years): 2010~2016 Korea National Health and Nutrition Examination Survey (우리나라 19-69세의 수면시간에 따른 견과류 섭취와 고혈압의 연관성: 2010~2016 국민건강영양조사 자료를 이용하여)

  • Fan, Xueying;Kim, Yookyung;Shin, Woo-Kyoung
    • Journal of Korean Home Economics Education Association
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    • v.33 no.4
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    • pp.103-117
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    • 2021
  • Nuts are cholesterol free with high poly-unsaturated fatty acids(PUFA) and have lower intakes of sodium than non-consumers, and thus they can decrease blood pressure. Hypertension is a common primary diagnosis in Korea. Because of extending exposure to 24-hour raised blood pressure and heart rate hypertension is likely to be caused by prolonged short sleep durations. This study examined the relationship between nut consumption and hypertension according to sleep duration among Korean adult. Based on data from the 2010-2016 Korea National Health and Nutrition Examination Survey(KNHANES), the final analytic sample(n=25,359) was used for current analysis. The dietary intake was assessed through a 24-hour recall method. Associations of nut consumption with sleep duration and hypertension were determined using multiple logistic regression with odds ratio(95% CI). All the analyses were carried out in SAS version 9.4, and the significance level was set at p<0.05. With increasing nut intake, the prevalence of hypertension significantly decreased(p for trend=0.02). After controlling for sleep duration, the nut consumption showed significant association with the prevalence of hypertension when sleep duration was 6 to 6.9 h per day(p for trend=0.03) or 7 to 7.9 h per day(p for trend=0.03). In conclusion, dietary total nut intake was found to be significantly associated with the prevalence of hypertension.