• Journal of fish pathology
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• v.12 no.1
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• pp.32-41
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• 1999

Ozonization for rearing seawater in land-based culture system has recently been utilized for disinfection of pathogenic microorganisms and improvement of water quality. This study was conducted to examine the effects of total residual oxidants (TRO) in ozone-treated seawater on survival, blood parameters, osmolality and oxygen consumption, and gill tissue of the flounder. Paralichthys olivaceus. Experiments were carried out with the starved flounder of 12~19 cm in total length at $20^{\circ}C$. The 48-hr and 96-hr $LC_{50}$ for the flounder amounts to 26.4 ppb and 22.3 ppb, respectively. With increase of TRO concentration from 24 to 39 ppb, the values of hematocrit, hemoglobin concentration, red blood cell count and osmolality of the flounder with respect to exposure time were significantly elevated, however, the oxygen consumption rates decreased. In the case of the fish exposed to 13 ppb for 96 hrs, blood glucose increased with an elapse of exposure time, while survival rate was 100%. Death apparently resulted by massive destruction of gill lamellar epithelium, severe osmotic imbalance and the lack of oxygen uptake. The results of this experiment indicated that to protect aquaculture organisms, the ozone-treated seawater should not contain any residual oxidants, and that relatively long-term exposure to TRO of low concentration can impact on survival and physiological conditions of the flounder.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.787-793
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• 1998

Physicochemical properties of starch of three cultivars of Korean kidney Bean Starches, Pink (PKB), Red (RKB) and White (WKB) were studied. Starch granule was oval/round and smooth in all samples. The amylograms showed a continuous increase of viscosity without peak during heating. The water-binding capacities of starches of PKB, RKB and WKB were 102.1%, 94.7% and 106.9%, respectively. The swelling powers were rapidly incresed in all samples. The amylose content, blue value and relative viscosity of kidney bean starches were $31.1{\sim}32.8%,{\;}0.64{\sim}0.66$ and $2.27{\sim}2.61{\;}mlg^{-1}$, respectively. The transmittance of starch suspension was linearly increased as the temperature raised from $65^{\circ}C{\;}to{\;}85^{\circ}C$. The gelatinization temperature ranges determined by differential scanning calorimetry (DSC) were $71.1{\sim}86.9^{\circ}C for PKB, $71.1{\sim}86.0^{\circ}C$ for RKB and $60.8{\sim}77.9^{\circ}C$ for WKB.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.558-566
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• 2017

In this study, we developed an electron-emission OH radical generator for waste water treatment. The stability of the circuitry was ensured by implementing stable pulse waves with a MOSFET and reducing the momentary current rise. The OH radical generator uses a high-voltage and low-current discharger. The performance of the device was evaluated experimentally, which showed that it is possible to produce a stable and uniform pulse waveform for the drain current of the power MOSFET, which is connected to the input side of an AC multiplying converter through negative feedback circuitry with CR-snubber architecture. It was also possible to reduce the excitation current of the converter and improve the stability of the oscillation circuit. In addition, the generator can generate hydroxyl radicals stably. The bactericidal activities were also evaluated, and the germicidal power for E. coli, S. aureus, and S. flexneriwas improved by 99.9% or more after 60 minutes.

• Journal of Nutrition and Health
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• v.26 no.5
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• pp.615-624
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• 1993

The body fat distribution and nutritional state of the Korean and Japanese young female subjects were compared. Three-day individually weighed, dietary intakes and anthropometric measurements were determinded in 48 Korean and 60 Japanese female students. 19 to 23 yr of age, from the divisions of nutritions. The body composition estimates were measured by bioeletrical impedance-total body water(BI-TBW) method. There were no significant difference between the Korean and Japanese young females in body size and body shape. The Korean young females had lower estimated total body fat and internal fat that calculated by BI-TBW method, but there was no great difference between the Korean and the Japanese in subcutaneous fat. In contrast, the Korean young females are reported to have the same total energy expenditure per day as the Japanes young females and the total energy intakes and carbohydrate energy intake ratio per day were significantly higher than those of the Japanese young females. The difference in body fat distribution and energy intakes in Korean, and the role of capsaicin in red pepper are discussed as a possible determinant of the internal fat in the Korean vs the Japanese.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.177-183
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• 2021

Distribution aspects and extinction threat evaluation of the endangered species, Rhynchocypris semotilus were investigated in Goseong-gun, Gangwon-do, Korea, June 2020. Among the 12 sampling sites investigated during the study period, samples of R. semotilus were collected 268 individuals at 6 sites. The streams inhabited of R. semotilus were Songhyeoncheon (3 stations), Gojindong (2 stations) and Osodong (1 station). The main habitats of R. semotilus were uppermost and upper stream (Aa type) with 3~15 m water flow width, 0.3~1.3 m depth and high ratio boulder and cobble bottoms. The estimated age of the R. semotilus (June) based on their total length distribution indicated that 0-, 1-, 2-, 3- and more than 4-year-old were 6~27 mm, 38~59 mm, 60~75 mm, 78~93 mm and 96~125 mm, respectively, and their has matured reproductive organs over two years old. R. semotilus investigation results of the threat of extinction showed no tendency to decrease in population size, but estimated to be less than 1,000 mature individuals, with a small range of extend of occurrence (39.668 km²), area of occupancy (16 km²), and number of disconnected locations (3 locations). Therefore, R. semotilus is now considered vulnerable (VU D2) based on the IUCN Red List categories and criteria.

• Laboraroty Animal Research
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• v.34 no.4
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• pp.302-310
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• 2018

CD47 (integrin-associated protein), a multi-spanning transmembrane protein expressed in all cells including red blood cells (RBCs) and leukocytes, interacts with signal regulatory protein ${\alpha}$ ($SIRP{\alpha}$) on macrophages and thereby inhibits phagocytosis of RBCs. Recently, we generated a novel C57BL/6J CD47 knockout ($CD47^{-/-}$ hereafter) mouse line by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease, and here report their hematological phenotypes. On monitoring their birth and development, $CD47^{-/-}$ mice were born viable with a natural male-to-female sex ratio and normally developed from birth through puberty to adulthood without noticeable changes in growth, food/water intake compared to their age and sex-matched wild-type littermates up to 26 weeks. Hematological analysis revealed a mild but significant reduction of RBC counts and hemoglobin in 16 week-old male $CD47^{-/-}$ mice which were aggravated at the age of 26 weeks with increased reticulocyte counts and mean corpuscular volume (MCV), suggesting hemolytic anemia. Interestingly, anemia in female $CD47^{-/-}$ mice became evident at 26 weeks, but splenomegaly was identified in both genders of $CD47^{-/-}$ mice from the age of 16 weeks, consistent with development of hemolytic anemia. Additionally, helper and cytotoxic T cell populations were considerably reduced in the spleen, but not in thymus, of $CD47^{-/-}$ mice, suggesting a crucial role of CD47 in proliferation of T cells. Collectively, these findings indicate that our $CD47^{-/-}$ mice have progressive hemolytic anemia and splenic depletion of mature T cell populations and therefore may be useful as an in vivo model to study the function of CD47.

• Journal of Life Science
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• v.29 no.4
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• pp.447-454
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• 2019

Fat accumulation in adipocytes occurs through the process of adipogenesis in which preadipocytes differentiate into adipocytes. Obesity is a metabolic disorder caused by excessive accumulation of fat in the body, which increases the incidence of cardiovascular diseases, hypertension, type 2 diabetes, hyperlipidemia, and various cancers. Recently, inhibition of adipocyte differentiation was shown to be a potential antiobesity strategy. In this study, the inhibitory effect of dichloromethane fractions from Illicium verum Hooker fil. water extract on the differentiation of 3T3-L1 preadipocytes to adipocytes was investigated. Dichloromethane fractions from I. verum Hooker fil. significantly inhibited adipocyte differentiation when applied during the adipocyte differentiation process, as assessed by measuring fat accumulation using Oil-red O staining. In addition, dichloromethane fractions from I. verum Hooker fil. reduced important adipogenic transcription factors, such as CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator activated receptor ${\gamma}$ ($PPAR{\gamma}$). The expression of FAS and LPL, which are terminal differentiation markers of mature adipocytes, was also reduced in the 3T3-L1 adipocytes treated with dichloromethane fractions from I. verum Hooker fil. In addition, the treatment significantly inhibited mitotic clonal expansion, which is essential for adipocyte differentiation, by arresting the G1 phase of the cell cycle. Taken together, these results suggest that dichloromethane fractions from I. verum Hooker fil. may be a natural material with antiobesity effects.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.4
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• pp.573-585
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• 2019

The objective of this study is to propose the drainage system that has been improved the workability, waterproofing and drainage performance to treat the leakage from the cement concrete structures in underground. It is improved that the pipe for conveying ground leak in the existing drainage system had the problem in workability and waterproof. The drainage systems with the improved pipe for conveying ground leak were constructed in conventional concrete lining tunnels to evaluate the workability, waterproofing and drainage. The waterproof and the drainage performance of the drainage system was evaluated by injecting 1,000 ml of red water in the back of the drainage system at 3 weeks, 6 weeks, 9 weeks, 11 weeks, 14 weeks, 17 weeks and 23 weeks. During 6 months of field performance test, the average daily temperature of the tunnel site was measured from $-12.4^{\circ}C$ to $19.7^{\circ}C$. The daily minimum temperature was $-17.2^{\circ}C$ and the daily maximum temperature was $26.7^{\circ}C$. There was no problem in waterproof and drainage performance on the pipe for conveying ground leak and the drainage system during 6 months for field performance test. It is concluded that the improved drainage system can be applied to various cement concrete underground structures where leakage occurs, and has little seasonal effect.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1177-1192
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• 2018

The objective of this study is to develop the existing drainage system for catching the partial leakage of tunnel structures operating in cold region. The drainage system consists of drainage board, Hotty-gel as a waterproofing material, cover for preventing protrusion of Hotty-gel, air nailer, fixed nail, pipe for collecting ground leak, pipe for conveying ground leak, wire-mesh, and sprayed cement mortar. The drainage systems were installed in conventional concrete lining tunnels to evaluate the site applicability and constructability. The performances of waterproof and the drainage in the drainage system were evaluated by injecting 1,000 ml of red water in the back of the drainage system at 7 days, 14 days, 21 days, 28 days, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months and 8 months. During 8 months of field test, the average daily temperature of the tunnel site was measured from $-16.0^{\circ}C$ to $25.6^{\circ}C$. The daily minimum temperature was $-21.3^{\circ}C$ and the daily maximum temperature was $30.8^{\circ}C$. There was no problem in waterproof and drainage performance of the drainage board in the drainage system. However, the pipe for conveying ground leak had the leakage problem from 14 days. It is considered that the leakage of the pipe for conveying ground leak was caused by the deformation of the pipe of the flexible plastic material having a thickness of 0.2 cm by using the high pressure air nailer and the fixing pin and the insufficient thickness and width of the hotty-gel for preventing the leakage.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.397-410
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• 2018

When considering the long-term safety assessment of spent-nuclear fuel management, americium is one of the most radio-toxic actinides. Although spectroscopic methods are widely used for the study of actinide chemistry, application of those methods to americium chemistry has been limited. Herein, we purified $^{241}Am$ to obtain a highly pure stock solution required for spectroscopic studies. Quantitative and qualitative analyses of purified $^{241}Am$ were carried out using liquid scintillation counting, and gamma and alpha radiation spectrometry. Highly sensitive absorption spectrometry coupled with a liquid waveguide capillary cell and time-resolved laser fluorescence spectroscopy were employed for the study of Am(III) hydrolysis and oxalate (Ox) complexation. $Am^{3+}$ ions under acidic conditions exhibit maximum absorbance at 503 nm, with a molar absorption coefficient of $424{\pm}8cm^{-1}{\cdot}M^{-1}$. $Am(OH)_3(s)$ colloidal particles formed under near neutral pH conditions were identified by monitoring the absorbance at around 506-507 nm. The formation of ${Am(Ox)_3}^{3-}$ was detected by red-shifts of the absorption and luminescence spectra of 4 and 5 nm, respectively. In addition, considerable enhancements of the luminescence intensities were observed. The luminescence lifetime of ${Am(Ox)_3}^{3-}$ increased from 23 to 56 ns, which indicates that approximately six water molecules are replaced by carboxylate ligands in the inner-sphere of the Am(III). These results suggest that ${Am(Ox)_3}^{3-}$ is formed through the bidentate coordination of the oxalate ligands.