• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.272-278
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• 2008

Optimum concentration of alizarine complexone (ALC) for staining of otoliths for Pacific cod was determined by examination of stained quality, growth and survival rates. Small juveniles ($34.1{\pm}1.8mm$ TL, $mean{\pm}SD$) were immersed in four different concentrations (20, 40, 60, 80 mg/L) and large ones ($73.8{\pm}1.2mm$ TL, $mean{\pm}SD$) in five different concentrations (1, 5, 10, 20, 40 mg/L) of ALC for 24 hrs. The fish were then reared and observed for 14 days. The stained quality of otoliths was evaluated by dividing them into four grades by the presence of fluorescent stains on the otoliths under G-excited UV light. The small juveniles stained with the different ALC concentrations had 100% staining success, and their growth rate and body weight did not differ significantly between treatments. Optimal ALC concentration for the smaller juveniles was 20 mg/L in the present experiment. On the other hand, distinct fluorescent rings were confirmed on otoliths of larger juveniles in the 10 mg/L treatment with high survival rate. These results suggest that ALC staining at concentrations of 10 mg/L with larger juveniles will be helpful for release-recapture experiments for stock enhancement of Pacific cod.

• Journal of Life Science
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• v.28 no.7
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• pp.811-818
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• 2018

This study was performed to investigate the localization and concentration changes of mercury compound in female reproductive organs with time. Methylmercuric chloride was subcutaneously injected weekly into pubescent female mice for 3 weeks. For the concentration changes of mercury with time, the mice were sacrificed at 10, 150, and 300 days post treatment (DPT). Body and organ weights were not significantly different between the control and mercury-treated groups, except for 10 DPT in body weight. Localization of accumulated mercury was identified by the autometallography method. Localization of mercury compounds in the uterus, ovary, and ovum was analyzed with a light microscope. In the uterus, mercury was densely located in the stroma cells and surface epithelium of the perimetrium at 10 DPT. Mercury concentration was decreased at 150 DPT and did not appear at 300 DPT. In the ovary, mercury particles were distributed in the stroma cells of the cortex region, cells of the theca around the follicle, and the corpus luteum at 10 DPT. Mercury was concentrated in the medulla region at 150 DPT and was not distributed at 300 DPT. In the ovum, mercury particles were mainly located in the marginal region at 10 and 150 DPT. Mercury concentration was decreased and evenly distributed at 300 DPT. These results suggest that hormone synthesis, implantation, and developing embryos will be affected by mercury compound in the female mouse.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.1-10
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• 1998

The early history of Korean mandarin fish, Siniperca scherzeri was studied to obtain some information required in aquaculture and reinforcement of natural population. During the period from June 1996 to July 1997, the mature adults of Siniperca scherzeri were collected from the middle Soyang Lake at Puksan - myon, Chunchon - shi, Kangwon - do, Korea. The eggs from females were obtained by injecting HCG or/and GnRH - a and fertilized by dry method in the laboratory. The fertilized eggs, measuring 1.70~2.10 mm in diameter and expanded to 2.20~2.66mm after absorption of water, were globosity, light orange yellow, separative, submergence and had one large oil globules of 0.5~0.7 mm. The blastodisc was formed in 1 hour and cleavage started in 1 hour 30 min. after fertilization, and the intervals of each stage of cleavage was about 50 min. at the water temperature of $21{\sim}24^{\circ}C$. Hatching occurred 131 hours 30 min. after fertilization and newly hatched larvae were 5.86~6.85 mm in total length(TL) and numerous stellate melanophores were distributed on the yolk and abdomen of caudal peduncle. The yolk was almost absorbed and the teeth development. 3 days after hatching, at 6.98~7.60 mm TL. The head spines and the teeth were largely developed and all fins were completely formed and became postlarva stage 15 days after hatching, at 10.10~12.90 mm TL. The body shape and the color pattern were similar to adult, 25 days after hatching, at 15.3~23.8 mm TL. In 5 months after hatching were reached at 154.10~175.02 mm TL and 49.32~82.67 g in body weight.

• Journal of Pharmacopuncture
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• v.13 no.2
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• pp.13-31
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• 2010

Objective : Bujeonghangam-tang(BH) has been used for cure of tumor as a traditional medicine. This study was carried out to clarify the effect of BH extract on hepatocellular carcinogenesis and hepatic cirrhosis induced by Diethylnitrosamine(DENA) and $CCl_4$ in Rats. Method : Experimental groups were divided into two, 8th and 12th week groups, and subdivided into four; normal group(Nor), cirrhosis and hepatic cancer inducing control group(Con), and BH extract 320 mg/kg/day(BHA) or 640 mg/kg/day(BHB) administered groups to Con. Results: In the 8th week group: The body weight decreased significantly in Con compared with the Nor. The activities of transaminase, alkaline phosphatase(ALP), and lactacte dehydrogenase(LDH) were significantly increased(p<0.05) in the Con compared with Nor, but decreased in the BHA and BHB compared with Con. Alpha fetoprotein(AFP) were the most increased in the Con compared to BHA and BHB. The results of light microscopical observation, a number of hepatocytes were damaged in the Con compared with Nor and BH extract administerd groups. The number of hepatic p53 positive cells was reduced in the BH extract administered groups. According to the electron microscopical observation, hepatocarcinoma cells were observed distinctly in the Con compared with BH extract administered groups. In the 12 weeks group: The results of body were similar to 8th week groups. The activities of transaminase and ALT were significantly increased(p<0.05) in the Con compared with Nor. LDH was significantly(p<0.05) increased in the Con compared with Nor but significantly (p<0.05) decreased in the BHB. Alpha fetoprotein(AFP) were the most increased in the Con among ex perimental groups. The activities of superoxide dismutase(SOD) were significantly (p<0.05) increased in the Con, but the activities of catalase were not increased(p<0.05) compared with Nor. The number of hepatic p53 positive cells was increased in the Con. The results of electron microscopical observation were similar to 8th week groups. Conclusion : These results suggest that ad ministration of BH extract suppress or retard DENA and $CCl_4$-induced hepatocellular carcinogenesis and hepatic cirrhosis in rats.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.1
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• pp.49-61
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• 2007

Otter boards in the trawl are the one of essential equipments for the net mouth to be spread to the horizontal direction. Its performance should be considered in the light of the spreading force to the drag and the stability of towing in the water. Up to the present, studies of the otter boards have focused mainly on the drag and lift force, but not on the stability of otter boards movement in 3 dimensional space. In this study, the otter board is regarded as a rigid body, which has six degrees of freedom motion in three dimensional coordinate system. The forces acting on the otter boards are the underwater weight, the resistance of drag and spread forces and the tension on the warps and otter pendants. The equations of forces were derived and substituted into the governing equations of 6 degrees of freedom motion, then the second order of differential equations to the otter boards were established. For the stable numerical integration of this system, Backward Euler one of implicit methods was used. From the results of the numerical calculation, graphic simulation was carried out. The simulations were conducted for 3 types of otter boards having same area with different aspect ratio(${\lambda}=0.5,\;1.0,\;1.5$). The tested gear was mid-water trawl and the towing speed was 4k't. The length of warp was 350m and all conditions were same to each otter board. The results of this study are like this; First, the otter boards of ${\lambda}=1.0$ showed the longest spread distance, and the ${\lambda}=0.5$ showed the shorted spread distance. Second, the otter boards of ${\lambda}=1.0$ and 1.5 showed the upright at the towing speed of 4k't, but the one of ${\lambda}=0.5$ heeled outside. Third, the yawing angles of three otter boards were similar after 100 seconds with the small oscillation. Fourth, it was revealed that the net height and width are affected by the characteristics of otter boards such as the lift coefficient.

• Journal of Mushroom
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• v.17 no.3
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• pp.119-125
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• 2019

This study aims to report the results for the analysis of the growth environment by applying smart farm technology to "Chunchu No 2" farmers in order to develop an optimal growth model for precision cultivation of bottle-grown oyster mushrooms. The temperature, humidity, carbon dioxide concentration, and illumination data were collected and analyzed using an environmental sensor installed to obtain growth environment data from the oyster mushroom cultivator. Analysis of the collected temperature data revealed that the temperature at the time of granulation was $19.5^{\circ}C$ after scraping, and the mushroom was generated and maintained at about $21^{\circ}C$ until the bottle was flipped. When the fruiting body grew and approached harvest time, mushrooms were harvested while maintaining the temperature between $14^{\circ}C$ and $18^{\circ}C$. The humidity was maintained at almost 100% during the complete growth stage. Carbon dioxide concentration gradually increased until 3 days after the beginning of cultivation, and then increased rapidly to almost 5,500 ppm. From the 6th day, carbon dioxide concentration was gradually decreased through ventilation and was maintained at 1,600 ppm during harvest. Light intensity of 8 lux was irradiated up to day 6 after seeding, and growth was then continued while periodically irradiating 4 lux light. The fruiting body characteristics of "Chunchu No 2" cultivated in the farmhouse were as follows: pileus diameter of 26.5 mm and thickness of 4.9 mm, stipe thickness of 8.9 mm, and length of 68.7 mm. The fruiting body yield was 166.8 g/850 ml, and the individual weight was 12.8 g/10 units.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.244-253
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• 2007

In this study, mortality, body wet weight, health assessment, and short-term behavioral mode were observed to determine the effects of ultrasound on the ecological response of the carp Cyprinus carpio. Mortality in the treatments was less than 5% during ultrasound exposure (31 dB re 1 ${\mu}Pa$, $14{\sim}15$ kHz) and there were no significant differences among the replicates (P>0.05). The treatments, based on mean wet weight, exhibited greater effect than the controls, but the magnitude of the differences was not large. Skins and tail fins of some test animals exposed to the controls and intensive treatment groups had light injury such as hemorrhaging, whereas, damages in other organs such as eyes, other fins, parasites, thymus, and gills were not observed (P>0.05). Sudden stimuli in low intensity at a short distance caused a directional avoidance of the fish from the sound. However, the carp exposed to ultrasound at the large scale field was not observed clear behavior changes. Overall results suggest that fish exposed to the low-intensity ultrasound had no serious stress during the tests.

• Journal of Life Science
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• v.19 no.2
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• pp.213-218
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• 2009

The purpose of this study was to investigate the UCP-1, UCP-3 mRNA expression in brown adipose tissue with glycometabolism according to intensity and duration of swimming in rat. F344 rat were randomly divided into three groups (n=10 in each group): control (CON), low-intensity swimming (LIS) groups, and high-intensity swimming (HIS) groups. Animals in the LIS group were forced to swim in swimming pool for 30min once a day for 8 consecutive weeks with a light intensity. In the HIS group, the rats repeated fifteen 20-s swimming bouts with a weight equivalent to 10% of body weight for 8weeks, respectively. The present result demonstrated that in LIS group, serum insulin and glucose levels significantly decreased in LIS group compared to CON. Brown adipose tissue UCP-1 and UCP-3mRNA expression was significantly increase in LIS group compared to CON and HIS groups. From those results, it can be suggested that low-intensity swimming may improve glycometablism control by up-regulating UCP-1 and UCP-3mRNA expression.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.666-671
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• 2018

A honeycomb panel is a plate made by attaching two surface plateson eitherside of a honeycomb core. The honeycomb plate hasexcellent specific strength and energy absorption and is suitable for use in regions where good impact resistance is required. Recently, with the increasing the need for a lightweight design to facilitate transportation, numerous studies have been conducted using aluminum honeycomb plates as body materials for vehicles such as automobiles and high-speed trains. In addition, honeycomb plates have excellent sound deadening properties, as well as excellent heat insulation and durability. Savings in weight using lightweight materials such as aluminum alloy for honeycomb panel's skin can lead to increase fuel economy and reduction in air pollution. In this study, in order to improve the design technology of the honeycomb plate material, the manufacturing technology of the aluminum honeycomb core and honeycomb plate material and various mechanical properties of the honeycomb plate were evaluated. From the results, it was found that the design of the manufacturing process of the aluminum honeycomb plate, as well as itsproduction and characteristics, were improved. The resulting excellent energy absorption capability of the honeycomb plate was due to the repetitive core buckling, indicating that the higher the compressive strength, the higher the strength per bonded area.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.651-659
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• 2015

Currently, social demands for long span building structures are increasing due to architectural planning purposes and economic efficiency. As a result, lighter board-type voiding materials were suggested. With the use of board-type voiding materials, a slab is able to become light weight and convenient. This process efficiently eliminates concrete where it is not required; considerably diminishing dead weight while maintaining the flexural strength of the slab. The reduction in concrete also allows for overall cost reductions and design flexibility. Also it can be ease with fixing the voided material that is composed of one body form. Although board-type voiding materials are ideal, the top and bottom concrete plates lack integrity. Because of this, test results show horizontal cracking towards the tops and bottoms of the concrete columns, or webs, connecting the slabs. The key to correcting this problem is to increase the shear strength. In order to increase the shear strength of the structure, horizontal shear area must increase. R70(100)-D-F has the largest horizontal shear area as it also shows stronger strength. As a result, shear strength ($V_{nh}$) is dependent on the horizontal shear area (N). $V_{nh}={\alpha}{\times}0.16{\sqrt{f_{ck}}}{\frac{{\pi}D^2}{4}}{\times}N({\alpha}=1.8125)$. The web columns have a shear span to depth ratio (a/d) that is less than 2; which classifies it as a deep beam. In this case, however, the shear strength of the deep beams may be as much as 2 to 3 times greater than that predicated conventional equations developed for members of normal proportions. As a result, ${\alpha}$ is suggested as an extra coefficient in the equation for shear strength ($V_{nh}$).