• Title/Summary/Keyword: cold exposure

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Safety Helmet Capable of Indicating the Worker's Risk Indices (근로자의 위험지수를 표시하는 안전모)

  • Gu, Jong-Hwa;Lee, Ho-Hyun;Lee, Kang-Suk;Chun, Myung-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.67 no.2
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    • pp.106-111
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    • 2018
  • Recently, due to the effect of global warming, the high temperature phenomenon continues, and the time for workers exposed to high temperature, cold and infrared is increasing and then safety is threatened. Due to the nature of on-site work, the work is being carried out in an unreasonable manner due to the process, which is exposed to disasters due to high temperature and cold. Even though the injured skin may be damaged, the worker may not be aware of it and may be injured. By understanding the working environment of the worker and calculating the risk index and expressing it on the helmet, the surrounding colleagues inform the worker of the risk and take appropriate measures so that the accident can be prevented in advance. This study was conducted to investigate the effect of exposure duration on the workers' by measuring the exposure time, the risk index is displayed in the form of a traffic light to the helm, informing neighboring workers and managers, and transmitting to the workers by voice.

A Study on the Construction of Cutting Scenario for Kori Unit 1 Bio-shield considering ALARA

  • Hak-Yun Lee;Min-Ho Lee;Ki-Tae Yang;Jun-Yeol An;Jong-Soon Song
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4181-4190
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    • 2023
  • Nuclear power plants are subjected to various processes during decommissioning, including cutting, decontamination, disposal, and treatment. The cutting of massive bio-shields is a significant step in the decommissioning process. Cutting is performed near the target structure, and during this process, workers are exposed to potential radioactive elements. However, studies considering worker exposure management during such cutting operations are limited. Furthermore, dismantling a nuclear power plant under certain circumstances may result in the unnecessary radiation exposure of workers and an increase in secondary waste generation. In this study, a cutting scenario was formulated considering the bio-shield as a representative structure. The specifications of a standard South Korean radioactive waste disposal drum were used as the basic conditions. Additionally, we explored the hot-to-cold and cold-to-hot methods, with and without the application of polishing during decontamination. For evaluating various scenarios, different cutting time points up to 30 years after permanent shutdown were considered, and cutting speeds of 1-10nullm2/h were applied to account for the variability and uncertainty attributable to the design output and specifications. The obtained results provide fundamental guidelines for establishing cutting methods suitable for large structures.

A Case of Cold Agglutinin Hemolytic Anemia Complicating Mycoplasma pneumoniae pneumonia in Children (소아에서 Mycoplasma pneumoniae pneumonia에 합병된 한냉응집소 용혈성 빈혈 1례)

  • Jo, Sung Ok;Park, Hyeon Jin
    • Pediatric Infection and Vaccine
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    • v.5 no.2
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    • pp.302-307
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    • 1998
  • Hemolytic anemia due to cold agglutinin disease is a known complication of Mycoplasma pneumoniae infection but is rarely observed, particularly in children. A case of Mycoplasma pneumonia complicated with hemolytic anemia is presented. A 7 year-old girl was adimitted because of fever, cough, sputum and pale appearance. Chest X-ray showed pneumonic consolidation of Rt. upper lobe, lingular division. Laboratory studies disclosed the following values : Hb 5.3g/dL, Hct 11.1%, reticulocyte 2.9%, indirect Coombs test negative, direct Coombs test(monovalent) Anti-C3d positive, Anti-IgG negative, Anti-IgM negative, cold agglutinin titer 1 : 256, mycoplasma antibody titer 1 : 640, total bilirubin 1.0mg/dL. Initial PBS before wanning showed agglutination of red blood cells. The diagnosis of cold agglutinin hemolytic anemia complicating mycoplasma pneumonia was made. And treatment with roxithromycin, prednisolone and avoiding cold exposure was initiated, and complete recovery ensued. We report a case of cold agglutinin hemolytic anemia complicating mycoplasma pneumonia in children.

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Effect of Cold Stress on Activities of Protein kinase C Subspecies in Rat Brain Regions

  • 이재란;최명언
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.259-259
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    • 1994
  • Protein kinase C (PKC) participates in many cellular signal transduction. Previously we found that PKC activity of whole rat brain was altered after an exposure to cold temperature of 4 $^{\circ}C$ (Lee and Choi, Exp. Neurobiol., 2, 6, 1993). In this time PKC activity in each region of rat brain was investigated in order to know each regions is affected mostly by the stress.

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Changes in Cell Ca2+ Distribution in Loquat Leaves and Its Effects on Cold Tolerance

  • Zheng, Guohua;Pan, Dongming;Niu, Xianqian;Wu, Hanwen;Zhang, Jinbiao
    • Horticultural Science & Technology
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    • v.32 no.5
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    • pp.607-613
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    • 2014
  • Calcium has been associated with improved cold tolerance in many crops. The aim of this study was to investigate the changes in leaf cell $Ca^{2+}$ distribution and cell organelle ultrastructure of loquat (Eriobotrya japonica Lindl.) plants in response to cold stress at $-3^{\circ}C$, using transmission electron microscopy (TEM). Two loquat accessions, Zaozhong 6 (a commercial cultivar) and oakleaf loquat (a wild relative) were used. Cold tolerance, as measured by leaf browning rate, was higher in oakleaf plants, and calcium treatment improved cold tolerance in both species. Cold stress first induced inward transport of $Ca^{2+}$ from the intracellular space. Then, the imported $Ca^{2+}$ was aggregated around the chloroplast membrane, finally entering the chloroplast. This pattern of $Ca^{2+}$ distribution in leaf cells occurred earlier in Zaozhong 6 than in the wild loquat. With increasing time of cold exposure, the chloroplast membranes of Zaozhong 6 leaves were damaged, blurred and even disappeared, while those of wild oakleaf loquat leaves maintained their structure longer. In Zaozhong 6, cold stress induced a clear cavity between poorly structured granal thylakoids and vesicles appearing inside the chloroplast, while in oakleaf leaves cold stress had little effect on the ultrastructure of chloroplasts (although chloroplast membranes looked blurred). Loquat leaves accumulated free calcium ions around chloroplasts in response to cold stress, with earlier calcium accumulation occurring in the cold-sensitive cultivar Zaozhong 6 than in wild oakleaf loquat. These results demonstrate that these two loquat species have differences in both cold tolerance and calcium accumulation dynamics.

Variation in Heading States of Korean Winter Wheat under Winter Temperature Rise of Toluca in Mexico (멕시코 톨루카 지역의 겨울 기온상승에 따른 한국 밀 품종의 출수생태 변이)

  • Park, TaeIl;Chung, Uran
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.3
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    • pp.99-108
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    • 2016
  • The shuttle breeding of Korean winter wheat has been able to develop high-yielding and day-length-intensive varieties with a wide range of ecologic adoption. However, the phenology of winter wheat has been changed due to recent rises in the winter temperature of Toluca and increasing frequency of high temperatures. We defined two wheat groups (group II and III) with vernalization and evaluated the impact of cold exposure duration and heading ratio due to changes in sowing dates by measuring changes in cold exposure duration and corresponding heading states of each group. The wheat cultivars were sown on three dates in two years. The cold exposure requirement of wheat sown on 6 November 2013 was unfulfilled. The cold exposure requirement of wheat sown on 22 November and 6 December 2013 was fulfilled. However, in 2014, the cold exposure requirement of wheat sown on 5 and 20 November was fulfilled, but that of wheat sown on 5 December was unfulfilled. The differences for the two early November sowings were because winter temperature rises, which caused high temperatures in 2013, whereas early November 2014 saw normal temperatures for the area. The heading ratio of group II did not show a clear difference among the three sowing dates, while the heading ratio of group III was reduced by about half. This implies that the efficiency of shuttle breeding of group III will be high since it showed strong sensitivity to changes in sowing dates. We calculated future sowing dates of each group under near future climate scenarios; the future available sowing dates of group II were projected, but the dates of group III were never estimated in the temperature rise scenario in Toluca. Our findings suggest that change of sowing dates should be considered in the strategy for shuttle breeding of Korean winter wheat.

A Study on Improvement Plan for Selecting Boundary Areas to Respond to Chemical Accidents and Terrorism (화학물질 사고·테러 대응을 위한 경계구역 선정 개선방안 연구)

  • Jeon, Byeong-Han;Kim, Hyun-Sub;Lee, Hyun-Seung;Park, Choon-Hwa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.8
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    • pp.60-66
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    • 2020
  • This paper presents a method for improving the selection of boundary areas suitable for Korea's situation based on domestic and foreign case studies on the establishment of boundary areas to protect people and the environment from chemical substances in response to chemical accidents and chemical terrorism. Currently, various related ministries are divided into hot zones, warm zones, and cold zones in common, but in specific areas, they are used in different ways in terms of terminology utilization. Therefore, it was suggested that the boundary areas be divided into four zones: hot zone, warm zone, cold zone, and safety zone. In addition, the terms warm zone and safety zone should be re-established. The existing ERPG acute exposure standard does not take into account various exposure times. Therefore, it is unsuitable for long-term exposure, so the priority of application should be AEGL, ERPG, PAC, and IDLHs. The CARIS information provision method is classified into substances that can or cannot be diffused or classified as indoor leaks. In addition, the wind direction trust line and the ERG's initial separation distance and protective action distance are expressed together so that they can be used for accident responses.

Effects of Buja${\cdot}$Padu${\cdot}$Daehwang${\cdot}$Seokgo Extract on UCPs Expression in Mice (부자${\cdot}$파두${\cdot}$대황${\cdot}$석고 추출물의 UCP 발현에 미치는 영향)

  • Kwon, Kang-Beom;Kim, Eun-Kyung;Kim, In-Seob;Hwang, Tae-Ok;Lee, Si-Woo;Lee, Su-Kyung;Choi, Jin-Young;Keum, Kyung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.6
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    • pp.1407-1410
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    • 2007
  • We designed to investigate the relationship the cold-hot theory of herbology and body temperature in experimental model. we prepared four kinds of oriental medicine, which consisted of two cold herbs, Daehwang and Seokgo, and two hot herbs, Buja and Padu. Decrease of body temperature by cold exposure for 12 hour was not inhibited by four herbs oral administration for two weeks. Thermogenesis in mammals is an essential physiological function to maintain the body temperature. Mitochondrial uncoupling proteins(UCPs), which have a potential to generate heat by uncoupling oxidative phosphorylation, apper to play a crucial role in thermogenesis. Therefore UCP is commonly recognized as a key molecule in metabolic thermogenesis and its dysfunction contributes to the development of obesity. In these experiments, Daehwang water extracts inhibited the UCP1 mRNA expression increase by cold exposure in brown adipose tissue. But other herbs did not significantly influence on UCPs mRNA expression in white adipose tissue and seleus muscle tissue. Based on this experiment, we will try to clarify the effects of Daehwang water extracts on UCP1 expression and function.

Tainting and Depuration in Fish by Petroleum Hydrocarbon (유류오염이 어체에 미치는 영향과 유성분 제거에 관한 연구)

  • 강석중;최병대
    • Journal of Aquaculture
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    • v.10 no.2
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    • pp.189-197
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    • 1997
  • A series of short (8 hours) and long term (96 hours) exposure studies was conducted on a laboratory scale to evaluation (1) the threshold concentrations of petroleum hydrocarbon in seawater which can lead to tainting problems in yellow tail (Seriola quinqueradiata) and (2) the time to recover (depuration period) once the tainting has occurred. The water-soluble fraction (WSF) of crude oil was prepared by stirring the oil with cold seawater. The main component of the WSF were low-boiling aromatics, although these were only al small proportion of the starting oil. From the sencory evaluation it was concluded that the threshold hydrocarbon levels in seawater which will impart a taint in yellow tail fillets within a 8-hour exposure period (short exposure period) are in the range of 0.4 to 1.0 ppm and within a 96-hour exposure period (long exposure period) are in the range of 0.2 to 0.5 ppm. Depuration trials were carried out with WSF from crude oil. The fish were exposed for 48 hours to concentration of 2.5 ppm hydrocarbons. After 48-hour exposure period, the fish were allowed to depurate in fresh, uncontaminated seawater. Depuration time for these fish was 10 days. The taste panelists were able to detect the contaminated fillets very easily while the depurated fish could not be distiguished from the control.

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Effect of Cold Adaptation on the Improved Viability of Lactobacillus crispatus KLB46 (Lactobacillus crispatus KLB46의 생균제제화를 위한 저온 전처리시 증지의 효과)

  • 김주현;이석용;장정은;김승철;윤현식;소재성
    • KSBB Journal
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    • v.16 no.6
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    • pp.626-631
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    • 2001
  • Lactobacilli have been considered to play important roles in the health of human vagina. They secrete inhibitory substances to prevent vaginal infection by pathogenic organisms. In a previous study, we have isolated several lactobacilli from Korean woman and one of them (KLB46) was selected and indentified as Lactobacillu crispatus which showed high antimicrobial activity. In this study. cold adaptation prior to subsequent stresses exposure was examined whether L. crispatus KLB46 maintain the viability better than the non-adapted calls under stresses. For pharmaceutical formulation, the lyophilization process is required where stresses such as freezing/thawing and dehydration are routinely applied. Formulated L. crispatus KLB46 can be used for ecological treatment of bacterial vaginosis. The response of cold-adapted cells to other environmental stresses such as acid, heat, ethanol, NaCl, and H$_2$O$_2$ was also examined. The results showed that cold-adapted cells maintained higher survival rate compared with the non-adapted cells (freezing-thawing. 3-folds; dehydration: 3-folds; acid, 3-folds; heat, 10-folds). However, we did net observe any positive effect of cold adaptation on other stresses such as ethanol, NaCl and H$_2$O$_2$. When chloramphenicol was added during cold adaptation, adaptation effect was abolished. This confirms that de novo protein synthesis is necessary during the adaptation process. Moreover, we have identified cold shock protein homolog that codes for a major cold shock protein by PCR amplification using degenerate primers.

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