• Title/Summary/Keyword: Normal Dispersion

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Safety Pharmacology of CJ-11555 (CJ-11555의 안전성 약리실험)

  • 최재묵;이성학;김일환;박지은;김덕열;노현정;김택로;최광도;김영훈
    • Toxicological Research
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    • v.20 no.2
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    • pp.159-166
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    • 2004
  • Safety pharmacological properties of CJ-11555, an anti-cirrhotic agent, were investigated in experimental animals and in vitro test system. CJ-11555 had no effects on normal body temperature in rats, motor coordination, chemoshock induced by pentetrazol, electric shock induced by electric shocker and writhing syndromes in mice at dose levels of 100, 300 and 1,000 mg/kg. CJ-11555 inhibited intestinal activity and prolonged hexobarbital-induced sleeping time in mice at the dose level of 1,000 mg/kg. CJ-11555 affected on general activity and behaviour tests in SD rats, such as lacrimation, ptosis, piloerection, decreased body tone, abnormal dispersion within the cage, diarrhoea, red colored faeces, slight hypothermia and decreased grooming, at the dose level of 1,000 mg/kg in rats. CJ-11555 was effected on cardiovascular and respiratory system in anesthetized beagle dogs, such as tachycardia, increase of mean blood pressure and decrease of PR interval, decrease of respiratory rate and minute volume, at dose levels of 10 and 30 mg/kg. However, these effects were also observed in vehicle treated anesthetized beagle dogs. In in vitro experiments, CJ-11555 inhibited agonists (histamine, acetyl-choline or $BaCl_2$) induced contraction of isolated guinea-pig at the concentration of 30$\times$$10^6$ M. CJ-11555 was weekly inhibited hERG channel current at concentrations of 10 and 30$\times$$10^6$ M, and $IC_{50}$ was estimated to be higher than 30${\times}$$10^6$M. Based on these results, it was concluded that CJ-11555 affected on cardiovascular and respiratory system, general activity and behaviour and hexobarbital-induced sleeping time at the dose level of 1,000 mg/kg and contraction of the smooth muscle and hERG channel current at the concentration of 30$\times$$10^6$ M.

Phase Transition and Relaxor Behaviors in the Lead Magnesium Niobate-based Ferroelectrics (Pb(Mg1/3Nb2/3)O3-based 강유전체의 상전이 및 완화특성)

  • Kim, Y.J.;Lee, J.H.
    • Journal of the Korean Vacuum Society
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    • v.17 no.2
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    • pp.148-155
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    • 2008
  • Dielectric and pyroelectric properties of relaxor ferroelectric in the PMN-PT solid solution series have been investigated. Features of the diffuse phase transition in PMN-PT system, typical relaxor ferroelectric materials, were studied as a function of temperature and frequency. The transition temperature of the ceramics with PT$\sim$0.325 did not depend on the measuring frequency. This can best realized in a relatively random environment that apparently is provided by PMN-rich complex perovskites, including those containing Pb. The composition with PT>0.35 show the characteristics of a normal single phase ferroelectric material. Thus the studies revealed that the morphotropic phase boundary in the PMN-PT system is in the vicinity of PT$\sim$0.3 and it has a small curvature and as a result the compositions near the morphotropic phase boundary show two phase transitions, rhombohedral$\rightarrow$tetragonal$\rightarrow$cubic, when the samples are heated up to higher temperature. The best optimum compositions are observed near the morphotropic phase boundary.

Effect of Pressure Gradients on the Hairpin Structures in Turbulent Boundary Layers (난류 경계층의 Hairpin와 구조에 대한 압력구배의 영향)

  • Kim, Gyeong-Cheon;Yun, Hong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.8
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    • pp.1103-1112
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    • 2001
  • The effect of pressure gradients on the hairpin structures in three different turbulent boundary layers (ZPG : Re(sub)$\theta$=910, FPG : Re(sub)$\theta$=575, APG : Re(sub)$\theta$=1290) has been examined with instantaneous velocity fields obtained in streamwise-wall-normal planes using PIV (particle image velocimetry) method. In the outer layer hairpin vortices occur in streamwise-aligned packets that propagate with small velocity dispersion. The signature pattern of the hairpin consists of a spanwise vortex core located above a region of strong second quadrant fluctuation (u<0 and v>0 : Q2 event) is clearly observed. The formation of packets explains the occurrence of multiple VITA events in turbulent burst. Noticeable differences are found in the average inclination angles of hairpin vortex packets which are 45$^{\circ}$, 35.7$^{\circ}$, and 51.9$^{\circ}$in the case of ZPG, FPG and APG, respectively. It is found that the large, time-varying, irregularly shaped zones with nearly constant streamwise momentum exist throughout the boundary layer. Within the interior of the envelope the spatial coherence between the velocity fields induced by the individual vortices leads to strongly retarded streamwise momentum, explaining the zones of uniform momentum. The formation of the uniform momentum zone is remarkably different with respect to the pressure gradients especially in the logarithmic layer.

RADIOLOGICAL DOSE ASSESSMENT ACCORDING TO METHODOLOGIES FOR THE EVALUATION OF ACCIDENTAL SOURCE TERMS

  • Jeong, Hae Sun;Jeong, Hyo Joon;Kim, Eun Han;Han, Moon Hee;Hwang, Won Tae
    • Journal of Radiation Protection and Research
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    • v.39 no.4
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    • pp.176-181
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    • 2014
  • The object of this paper is to evaluate the fission product inventories and radiological doses in a non-LOCA event, based on the U.S. NRC's regulatory methodologies recommended by the TID-14844 and the RG 1.195. For choosing a non-LOCA event, one fuel assembly was assumed to be melted by a channel blockage accident. The Hanul nuclear power reactor unit 6 and the CE $16{\times}16$ fuel assembly were selected as the computational models. The burnup cross section library for depletion calculations was produced using the TRITON module in the SCALE6.1 computer code system. Based on the recently licensed values for fuel enrichment and burnup, the source term calculation was performed using the ORIGEN-ARP module. The fission product inventories released into the environment were obtained with the assumptions of the TID-14844 and the RG 1.195. With two kinds of source terms, the radiological doses of public in normal environment reflecting realistic circumstances were evaluated by applying the average condition of meteorology, inhalation rate, and shielding factor. The statistical analysis was first carried out using consecutive three year-meteorological data measured at the Hanul site. The annual-averaged atmospheric dispersion factors were evaluated at the shortest representative distance of 1,000 m, where the residents are actually able to live from the reactor core, according to the methodology recommended by the RG 1.111. The Korean characteristic-inhalation rate and shielding factor of a building were considered for a series of dose calculations.

Modeling Human Exposure Levels to Airborne Volatile Organic Compounds by the Hebei Spirit Oil Spill

  • Kim, Jong-Ho;Kwak, Byoung-Kyu;Ha, Min-A;Cheong, Hae-Kwan;Yi, Jong-Heop
    • Environmental Analysis Health and Toxicology
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    • v.27
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    • pp.8.1-8.10
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    • 2012
  • Objectives: The goal was to model and quantify the atmospheric concentrations of volatile organic compounds (VOCs) as the result of the Hebei Spirit oil spill, and to predict whether the exposure levels were abnormally high or not. Methods: We developed a model for calculating the airborne concentration of VOCs that are produced in an oil spill accident. The model was applied to a practical situation, namely the Hebei Spirit oil spill. The accuracy of the model was verified by comparing the results with previous observation data. The concentrations were compared with the currently used air quality standards. Results: Evaporation was found to be 10- to 1,000-fold higher than the emissions produced from a surrounding industrial complex. The modeled concentrations for benzene failed to meet current labor environmental standards, and the concentration of benzene, toluene, orthometa- para-xylene were higher than the values specified by air quality standards and guideline values on the ocean. The concentrations of total VOCs were much higher than indoor environmental criteria for the entire Taean area for a few days. Conclusions: The extent of airborne exposure was clearly not the same as that for normal conditions.

Correlations between abnormalities of morphological details and DNA fragmentation in human sperm

  • Nguyen, Hiep Tuyet Thi;Dang, Hong Nhan Thi;Nguyen, Thai Thanh Thi;Nguyen, Trung Van;Dang, Thuan Cong;Nguyen, Quoc Huy Vu;Le, Minh Tam
    • Clinical and Experimental Reproductive Medicine
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    • v.49 no.1
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    • pp.40-48
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    • 2022
  • Objective: As the associations of sperm DNA fragmentation with morphology have not been examined in detail, this study aimed to investigate the relationship between abnormalities of morphological details and DNA integrity in human sperm. Methods: In this cross-sectional study, men from infertile couples were enrolled at Hue Center for Reproductive Endocrinology and Infertility, Vietnam. Conventional semen parameters, including morphological details, were analyzed following the World Health Organization 2010 criteria. Sperm DNA fragmentation was evaluated using a sperm chromatin dispersion assay. The relationships and correlations between semen parameters, sperm morphology, and the type of halosperm and the DNA fragmentation index (DFI) were analyzed. Results: Among 130 men in infertile couples, statistically significant differences were not found in the sperm halo type between the normal and abnormal sperm morphology groups. The percentage of round-head spermatozoa was higher in the DFI >15% group (16.98%±12.50%) than in the DFI ≤15% group (13.13% ±8.82%), higher values for amorphous heads were found in the DFI >15% group, and lower values for tapered heads were observed in the DFI ≤15% group; however, these differences were not statistically significant. Small-halo sperm and the DFI were positively correlated with round-head sperm (r=0.243, p=0.005 and r=0.197, p=0.025, respectively). Conclusion: The rate of general sperm morphological abnormalities in semen analysis was not related to sperm DNA integrity. However, round sperm heads were closely associated with sperm DNA fragmentation.

The Characteristics of Heavy Metal Contamination in Tailings and Soils in the Vicinity of the Palbong Mine, Korea (팔봉광산 선광광미와 주변토양의 중금속 오염 특성)

  • 이영엽;정재일;권영호
    • Economic and Environmental Geology
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    • v.34 no.3
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    • pp.271-281
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    • 2001
  • The characteristics of the heavy metal contamination in the soils affected by the tailings of the Palbong mine have been studied. The soils in the studied area consist mostly of loam by the particle size analysis, but a little of it, located near the stream, consist of loamy sand to sandy loam, finally to loam downward. The organic contents of soils are significantly low aoom 2 percent and the pH is in acidic ranging 6.0 $\pm$ 0.1. The samples of the parent rocks, the normal soils, the tailings and the channel deposits from the studied area were chemically analysed. From the result, the heavy metal concenlration of the soils is a little Jow compared with that of the parent rocks, shows the hydrologic process of the surface and the groundwater. The contamination of the tailings from the ore mining are high in lead, copper and arsenic. In the channel deposits the concenlrations of lead and copper are abnormally high but that of arsenic is uniquely low. And most of heavy metal contamination are decreased with the distance from the mine. It is caused by the properties of the surface and the ground water during the process of the heavy metal migration. The correlation-coefficient between sand and silt contents and the concentrations of Cd, Cu and Pb are significant but the amounts of As and Hg are increased with the clay contents. The dispersion of the heavy metals with the distance shows that the concentrations of them in the soils sampled at distance of 100 m to 200 m along the stream started near the Palbong mine are extremely high compared with those from other distances. These discrepancies are significant in Cd, Cu, Pb and Hg, but low in As. All the samples contain below detection limit of Cr+6 In the present stream water the concentrations of the heavy metals are not detected. So, it is interpreted that the concentrations in the soils are caused by the activities of the mining during the operation and have been continued by the dispersion from the tailings since after the closure of the mining, especially by the surface and ground water. The concentrations are diminished with the distance from the mining site, but in the interval of 800-2000 m increases abruptly. In the soil samples counted on the dispersion direction by wind, the lowering of the concentration is relatively uniform with the distance from the mining site. So, the rapid increase of the heavy metal concentrations is presumed to have been caused by the ground-water movement. In the migration of the heavy metals, the groundwater conditions, such as pH, Eh, the contents of colloidal particles, and Mn and Fe oxides are closely involveo. Integrating with these factors, it is interpreted that the groundwater conditions which have caused the heavy metal contamination of the studied area are those that the pH is about 3 in oxidized conditions, the contents of the colloidal particles are low, and Mn and Fe oxides are not involved in the migration of the heavy metals. Meanwhile, the vegetables growing on the soils in the studied area are not affected by the contamination of the heavy metals.

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Mechanical Properties of an ECC(Engineered Cementitious Composite) Designed Based on Micromechanical Principle (마이크로역학에 의하여 설계된 ECC (Engineered Cementitious Composite)의 역학적 특성)

  • Kim Yun-Yong;Kim Jeong-Su;Kim Hee-Sin;Ha Gee-Joo;Kim Jin-Keun
    • Journal of the Korea Concrete Institute
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    • v.17 no.5 s.89
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    • pp.709-716
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    • 2005
  • The objective of this study is to develop a high ductile fiber reinforced mortar, ECC(Engineered Cementitious Composite) with using raw material commercially available in Korea. A single fiber pullout test and a wedge splitting test were employed to measure the bond properties in a matrix and the fracture toughness of mortar matrix respectively, which are used for designing mix proportion suitable for achieving strain-hardening behavior at a composite level. Test results showed that the properties tended to increase with decreasing water-cement ratio. A high ductile fiber reinforced mortar has been developed by employing micromechanics-based design procedure. Micromechanical analysis was initially peformed to properly select water-cement ratio, and then basic mixture proportion range was determined based on workability considerations, including desirable fiber dispersion without segregation. Subsequent direct tensile tests were performed on the composites with W/C's of 47.5% and 60% at 28 days that the fiber reinforced mortar exhibited high ductile uniaxial tension property, represented by a maximum strain capacity of 2.2%, which is around 100 times the strain capacity of normal concrete. Also, compressive tests were performed to examine high ductile fiber reinforced mortar under the compression. The test results showed that the measured value of compressive strength was from 26MPa to 34 MPa which comes under the strength of normal concrete at 28 days.

Biomechanical Evaluation of Trekking Shoes using 3D Bootie Method as Mimics Barefoot Form (맨발 구조를 모사한 3D Bootie 공법을 적용시킨 트레킹화의 생체역학적 특성 평가)

  • Yoo, Chan-Il;Jeon, Keun-Hwan;Won, Yonggwan;Kim, Jung-Ja
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.7
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    • pp.4689-4696
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    • 2015
  • The purpose of this study was to evaluate biomechanical characteristics of trekking shoes using 3D Bootie method as mimics barefoot form of F Co. that provides the best comfort and plantar pressure dispersion. The control group is normal trekking shoes of M Co. and K Co.. 13 healthy males measured the foot pressure, EMG and GRF. Collected data was analyzed using One-way ANOVA in order to investigate the effects of each trekking shoes. The results are as follows: Trekking shoe of F Co. was significantly wider in contact area than others at MF and significantly lower in maximum force, peak pressure than others at RF. In the case of muscle activity, acted in the same way as the effect of barefoot walking. In the case of GRF, effectively absorbed the impact force, so it is possible to efficient walking. As a result of the analysis, trekking shoe using of 3D Bootie method of F Co. can be efficient walking by reducing the load of foot during walking.

Geochemical Exploration for Metallic Mineral Resources on the Pacitan District, East Java, Indonesia (인도네시아 빠찌딴지역 금속광물자원에 대한 지화학탐사)

  • Han, Jin-Kyun;Choi, Sang-Hoon
    • Economic and Environmental Geology
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    • v.44 no.1
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    • pp.1-10
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    • 2011
  • The geology of the Pacitan district which occupies Southern mountain zone in the southwestern margin of East Java, Indonesia, consists of a pile of clastics and pyroclastics grading upwards into a series of sediments of Middle Miocene age which are intruded by a number of quartz porphyries and subvolcanic dacitic to andesitic bodies in after that time. The geochemical exploration in the Pacitan district to find out anomalous areas related with metallic mineral dispersion from the concealed ore deposits had been carried out using traditional exploration techniques of geological mapping, stream sediment, panned concentrate and outcrop sampling. The anomalous zones of each element were detected in the following areas: Gempol for Cu; Jompong for Au; Kasihan for Cu-Pb-Zn. The strongest Cu-Pb-Zn anomalous values are overlapped at the Kasihan area. The geochemical survey of soil was conducted with the geological survey at the Kasihan area. The statistical values were calculated by the statistical analysis method. The patterns for Cu, Pb and Zn are similar to the normal distribution. The anomalous values of copper-lead-zinc and/or copper and zinc are overlapped at five zones surrounding quartz porphyry at the central part of the Kasihan area. The area was interpreted and chosen as an anomalous zone related with stockwork and skam mineralization, extending to approximately NNW-SSE direction.