• Title/Summary/Keyword: exposed times

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The Effect of a Pulsed Electromagnetic Field with Time on Pain in Muscle Crushed Rat Model

  • Kim, Min-Hee;Cheon, Song-Hee
    • Journal of Magnetics
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    • v.17 no.1
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    • pp.68-71
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    • 2012
  • Acute injuries to skeletal muscles can lead to significant pain and disability. Muscle pain results in muscle weakness and range of motion (ROM) decreases. Pulsed electromagnetic fields (PEMF) promote tissue repair, healing rates and reduce musculoskeletal pain. The results of many previous studies suggest that PEMF can contribute to chronic pain reduction, particularly in musculoskeletal injurys. However, we do not have enough information of its effects compared to a placebo. The principal objective of this study was to investigate differences in acute pain induced by the direct destruction of muscle tissue (extensor digitorum) with varying times of the application of PEMF, measured through the expression of c-fos on the spinal cord. Significant reduction of pain was found in groups exposed to PEMF and the group exposed to PEMF immediately after muscle injury showed the most significant differences. In conclusion, PEMF may be a useful strategy in reducing acute pain in muscle injury.

Physicochemical Changes in UV-Exposed Low-Density Polyethylene Films

  • Salem, M.A.;Farouk, H.;Kashif, I.
    • Macromolecular Research
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    • v.10 no.3
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    • pp.168-173
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    • 2002
  • Unstabilized low-density polyethylene (LDPE) films and films formulated with hindered amine light stabilizer (HALS) were exposed to UV-radiation; and the physicochemical changes during photooxidation processes have been investigated using tensile, FTIR spectre-photometric and thermal analytical (DSC) techniques. The dependence of tensile properties (elongation- and stress-at-break), carboxyl index and heat of fusion on UV-irradiation time have been discussed. The use of HALS is found to be effective in maintaining the UV-mechanical properties of the LDPE films. The experimental results showed that there exists no correlation between mechanical properties and carbonyl index, whereas crystallinity correlates well with carbonyl index in unstabilized and stabilized films for irradiation times greater than 100 h. The rate of formation of carbonyl groups is found to be dependent on UV exposure time. Crystallinity of the film samples is strongly influenced by both exposure time and presence of HALS.

Vitellogenin Production of Marine Fishes Exposed to E2 (17$\beta$-estradiol 처리에 따른 해산 어류의 vitellogenin 생성)

  • 황인영;박정규;이은경
    • Environmental Analysis Health and Toxicology
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    • v.16 no.1
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    • pp.21-28
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    • 2001
  • A common used endpoint in bioassays testing the estrogenicity of chemicals including endocrine disruptors is the induction of egg yolk Precursor vitellogenin in male fish. Two marine fishes (Sebastes schlegeli and Paralichthys olivaceus) were exposed to the 17$\beta$-estradiol(E2) to determine the vitellogenin production. Vitellogenin was measured in fish blood using SDS-PAGE and Densimetry. Results showed that exposure to E2 caused vitellogenin in male fish. Especially, vitellogenin levels in young fish were about 4 times higher than in adult fish, which means young fish are more sensitive to E2 exposure. And plasma vitellogenin in fish increased related to E2 concentration and exposure duration.

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Aging Characteristics of Composite Materials in Carbody of Tilting Train using Accelerated Aging Test (가속노화시험을 이용한 틸팅차량 차체 복합재의 노화특성)

  • Yoon Sung-Ho;Kim Yong-Goo;Nam Jung-pyo;Shin Kwang-Bok;Koo Dong-Hoe
    • Proceedings of the KSR Conference
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    • 2003.10c
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    • pp.333-338
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    • 2003
  • Polymeric composite structures used in ground transportation applications such as the carbody of tilting train may be exposed to a ground environmental conditions during long-term missions. In this study, the degradation of mechanical and physical properties of graphite/epoxy composite and glass fabric/phenol composite under ground environmental conditions was investigated. Accelerated environmental conditions of ultraviolet radiation, temperature, and moisture were considered. Several types of specimens were used to investigate the effects of environmental conditions on mechanical properties of the composites. Also, storage shear modulus, loss shear modulus, and tan 8 were measured as a function of exposure times through a dynamic mechanical analyzer. Finally, composite surfaces exposed to environmental conditions were examined using a scanning electron microscope.

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Health Effects of Mineral Dusts

  • Hayashi, Hisato
    • Journal of the Mineralogical Society of Korea
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    • v.10 no.1
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    • pp.1-17
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    • 1997
  • Pneumoconiosis is the result of the long-continued inhalation of dusts and it depends on the interaction between the man and the cloud to which he is exposed. The health effects of dusts, especially silica dust exposure have been since Egyptians had constructed the pyramids in ancient times. Subsequently, many works, including miners, milers, quarry workers, sandblasters, tunnel drivers, are occupationally exposed to mineral dusts. These workers may develop pneumoconiosis and in some instances, malignant neoplasms, particularly lung cancer, as a result of such exposures.Both quantity and quality of mineral dusts in the lungs show significant correlation with the degree of damage from pneumoconiosis. So mineralogical techniques require in pathological studies and in estimation of the airborne dusts in working places.Mineralogy has played an important role in both branches of the protective procedure. This lecture presents the knowledge on lung dust, cytotoxicity and fibrogenetic activity of minerals and control procedures for pneumoconiosis from pont of mineralogist.

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Risk Assessment for Heavy Metals in Soil, Ground Water, Rice Grain nearby Abandoned Mine Areas (국내 폐금속 광산지역에서의 토양, 지하수, 쌀의 중금속 노출에 따른 인체 위해성평가)

  • Na, Eun-Shik;Lee, Yong-Jae;Ko, Kwang-Yong;Chung, Doug-Young;Lee, Kyu-Seung
    • Korean Journal of Environmental Agriculture
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    • v.32 no.4
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    • pp.245-251
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    • 2013
  • BACKGROUND: The objectives of this study are to investigate the contamination levels of heavy metals in soil, ground water, and agricultural product near the abandoned Boeun and Sanggok mine areas in Korea and to assess the health risk for these local residents exposed to the toxic heavy metals based on analytical data. METHODS AND RESULTS: By the results of human health risk assessment for local residents around Boeun and Sanggok, human exposure to cadmium, copper, arsenic from soil and to lead, cadmium, and arsenic from rice grain were higher in Sanggok, but human exposure to zinc and arsenic from ground water was higher in Boeun. By the results of hazard index (HI) evaluation for arsenic, cadmium, copper, lead, and zinc, HI values in both areas were higher than 1.0. This result indicated that the toxicity hazard through the continuous exposure to lead, cadmium, arsenic from rice, ground water, and soil would be likely to occur to the residents in the areas. Cancer risk assessment for arsenic, risks from the rice were exposed to one to two out of 10,000 people in Boeun and one of 1,000 people in Sanggok. These results showed that the cancer risks of arsenic in both areas were 10~100 times greater than the acceptable cancer risk range of US EPA ($1{\times}10^{-6}{\sim}1{\times}10^{-5}$). CONCLUSION(S): Therefore, if these two local residents consume continuously with arsenic contaminated soil, ground water, and rice, the adverse health effects (carcinogenic potential) would be more increased.

Characterization of the Physical Form of Allergenic Cry j 1 in the Urban Atmosphere and Determination of Cry j 1 Denaturation by Air Pollutants

  • Wang, Qingyue;Morita, Jun;Gong, Xiumin;Nakamura, Shinichi;Suzuki, Miho;Lu, Senlin;Sekiguchi, Kazuhiko;Nakajima, Takuya;Nakajima, Daisuke;Miwa, Makoto
    • Asian Journal of Atmospheric Environment
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    • v.6 no.1
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    • pp.33-40
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    • 2012
  • In this study, we characterized the physical form of allergenic Cry j 1 in the urban atmosphere. Through an immunofluorescence antibody method, we showed that allergenic Cry j 1 exists as fine particles (${\leq}1.1{\mu}m$). To determine Cry j 1 concentrations and its particle size distribution, we used the ELISA method to confirm that most Cry j 1 exists as fine particles in the urban atmosphere and is found at high concentrations on fine day next to rainy day. Furthermore, we evaluated Cry j 1 denaturation by using the Biacore J system based on the surface plasmon resonence (SPR) principle and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We showed that the dissociation constant ($K_D$) of Cry j 1 that has been exposed to urban polluted air is lower ($1.76{\times}10^{-14}$ M) than that of Cry j 1 ($1.32{\times}10^{-9}-3.37{\times}10^{-9}$ M) of original pollen grains that has not been exposed to air pollutants. Cry j 1 turns into low molecular weight proteins by reacting with various acidic solutions. In sum, we showed that allergenic Cry j 1 exists as fine particles that can deposit in the lower respiratory tract. This finding clarifies the relationship between Japanese cedar pollinosis and air pollutants.

Micropatterning by Low-Energy Focused ton Beam Lithography(FIBL) (저에너지 집속이온빔리소그라피(FIBL)에 의한 미세패턴 형성)

  • 이현용;김민수;정홍배
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.224-227
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    • 1995
  • The micro-patterning by a Bow energy FIB whish has been conventionally utilized far mask-repairing was investigated. Amorphous Se$\_$75/Gee$\_$25/ resist irradiated by 9[keV]-defocused Ga$\^$+/ ion beam(∼10$\^$15/[ions/$\textrm{cm}^2$]) resulted in increasing the optical absorption, which was also observed also in the film exposed by an optical dose of 4.5${\times}$10$\^$20/[photons/$\textrm{cm}^2$]. The ∼0.3[eV] edge shift for ion-irradiated film was about twice to that obtained for photo-exposed. These large shift could be estimated as due to an increase in disorder from the decrease in the sloop of the Urbach tail. For Ga$\^$+/ FIB irradiation with a relatively low energy, 30[keV] and above the amount of dose of 1.4${\times}$10$\^$16/[ions/$\textrm{cm}^2$], the irradiated region in a-Se$\_$75/Ge$\_$25/ resist was perfectly etched in acid solution for 10[sec], which is relatively a short development time. A contrast was about 2.5. In spite of the relatively low incident energy,∼0.225[$\mu\textrm{m}$] pattern was clearly obtained by the irradiation of a dose 6.5${\times}$10$\^$16/[ions/$\textrm{cm}^2$] and a scan diameter 0.2[$\mu\textrm{m}$], from which excellent results were expected fur incident energies above 50[keV] which was conventionally used in FIBL.

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The assessment of health risk and subjective symptoms of printing workers exposed to mixed organic solvents (인쇄업 종사자의 혼합유기용제 노출로 인한 자각증상 및 위해성 평가)

  • Kim, Yeong-Mee;Kim, Hyunwook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.19 no.3
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    • pp.270-279
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    • 2009
  • In order to check a necessity of health control for the laborers who are in use of mixed organic solvents in the printing industries, this study evaluated the use status of mixed organic solvents, health subjective symptoms on the exposure of the solvents, health hazard for each kind of printings for the employees who work for the printing industries located in Seoul and Gyeonggi. The study analyzed 228 sites and 311 people responded of the total 250 sites surveyed from March to September 2007, and obtained the following results; 1) Estimating the exposure of the mixed organic solvents, the study found that estimation of mixture(EM) was different for each kind of printings at a level of significance, excessiveness of EM was 7.5%, the highest, for gravure printing, 5.6% for screen printing, 4.7% for master printing, 2.9% for offset printing. 2) As to the mean scores of health subjective symptoms for each kind of printings, workers in screen printing showed high scores in every subjective symptom, of which symptom of central nervous system was 3.75, the highest, and the difference was statistically at a level of significance(p<0.01). 3) Results of the hazard analysis for carcinogens and non-carcinogens contained in the mixed organic solvents exposed to the workers showed that cancer risk of offset printing workers was $7.8{\times}10^{-9}$ for benzene, the mean cancer risk was $2.02.{\times}10^{-8}$ from Monte-Carlo simulation, and both risks did not exceed the US EPA permissible standard of $1{\times}10^{-6}$. The total hazard indices of the non-carcinogens estimated was 3.523, the highest, for gravure printing, 2.381 for master printing, 1.125 for screen printing, respectively, and all exceeded 1.

The PPL Communication Effects of Fashion Brands in the Korean Movie - Focus on Setting Types and Exposure Times - (국내 영화 속 패션 제품의 PPL 커뮤니케이션 효과 - 배치 유형과 노출 시간을 중심으로 -)

  • Shin, Su-Yun;Hong, Jung-Min
    • The Research Journal of the Costume Culture
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    • v.15 no.1 s.66
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    • pp.13-24
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    • 2007
  • This study measured the communication effect on the setting types and the exposure times to perform the effective PPL strategies. By the setting types(on-set and creative) and exposure times(short and long), 308 female older than 20 were divided into 4 experimental groups. Each groups were exposed to the edited movies and required to answer the questionaire. The data were analysed by SPSS 12.0 using Chi-Square, One-Way ANOVA and Duncan test. The results are as follows. First, in cognitive dimension, the on-set type and long exposure group showed the higher recognition and recall. Second, in emotional dimension, the signigicant difference was found in one brand(Kappa) of two which were used in the experiment. In this case, the on-set type and long exposure group showed the positive attitude toward the brand. Third, in behavioral dimension, there were no difference among the groups. The implications based on this results are as follows. First, when implementing of PPL the fashion brands in movies, the on-set type and long exposure would be the most effective method. Second, implementing IMC(Integrated Marketing Communication) linked to the PPL strategy can be more effective. In contrast to the other product categories, it is hard to recognize the brand of fashion goods if the logo or the brand name is not exposed directly. Therefore Combining other communication strategies such as press release simultaneously will birng the more effective result of PPL in the movie.

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