• Applied Microscopy
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• 제27권2호
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• pp.189-196
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• 1997

The ultrastrucures of Xenopus otic vesicle from normal embryo (st. 43) and induced otic vesicle from animal cap assay with Activin A were compared. Activin A was applied to the presumptive ectoderm at various concentrations for three days at $20^{\circ}C$. The results were almost identical to the reference studies, but it was found that the otic vesicle was induced at the concentration of 10 ng/ml in to)v rate. This otic vesicle may be secondarily induced by the neural tissue showed commonly at the concentration of 10 ng/ml. Otoliths were observed as three or four-axis crystaline bodies in the lumen of otic vesicle. In electron micrograph of the normal embryo, two kinds of microvilli were observed on the apical position of hair cells. One was small and common, the other was large-sized and sparsely distributed. In both cell of otic vesicle, mitochondria, golgi apparatus and multivesicular body were rich, so, they showed a lot of similarities in ultrastructure. However, the otolith was not found and microvilli were overexpressed in the otic vesicle induced by Activin A.

• The Journal of Internal Korean Medicine
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• 제29권1호
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• pp.25-31
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• 2008

Objectives : The study was intended to investigate whether Iljoong-eum (IJE) significantly affects proliferation and growth of prostate cancer cells. Materials and Methods : In vitro, after the treatment of DU-145 and PC-3 cells with IJE, we performed Sulforhodamine B (SRB) method. In vivo, a total of 8 male nude mice subcutaneously transplanted with the PC-3 cell line were divided in 2 groups. An experimental group was given IJE orally at a dose of 4.29ml/kg per day from the 8th to 31st day following tumor injection. All mice were observed for 31 days, and sacrificed by CO2 gas asphyxiation at the end of the experiment. The mean tumor volume and body weight of both groups were compared using Student's t-tests. Results : In vitro, IJE inhibited significantly proliferation and growth of DU-145 cells and PC-3 cells. In vivo, IJE inhibited significantly proliferation and growth of PC-3 cells xenografted into athymic nude mice. Conclusions : Our data has shown that IJE is effective in suppressing the growth rate of prostate cancer cells.

• Journal of Embryo Transfer
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• 제7권1호
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• pp.21-30
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• 1992

This study was aimed to develope the new method for bovine sperm capacitation through testing and combinating factors relating to sperm capacitation. For verifying the efficiency of this method on inducing capacitation, in vitro fertilization was carried out. The results obtained were as follows: When pHs of HBS /PR for sperm-washing were 5.99, 6.38, 6.78, 7.10, 7.40, 7.69, 8.15, 8.45 and 8.83, variances between light absorhance differences obtained from sperm pre-washing solution and post-washing solution(VADs) were 0.000, 0.001, -0.001, -0.005, -0.005, -0.021,-0.017,-0.016,and-0.036, respectively. There were significant decreases of VADs in pH 7.69 and pH 8.83. When sperm were firstly, secondly, and thirdly washed with HBS /PR, VADs were -0. 024, - 0.006, and - 0.004, respectively. There was significant decrease of VAD in 1st sperm-washing. When washed-sperm were secondly washed with HBS /PR supplemented with no (con-trol), heparin, CSA, PC12, and BSA, VADs were 0.009, -0.024, -0.008, -0.009, and 0.014, respectively. When the sperm were thirdly washed with HBS /PR with no(control), heparin, CSA, PC12 and BSA, VADs were 0.020, -0.007, 0.005, 0.006, and 0.019, respectively. Only heparin treatment showed the negative values of VADs in 2nd and 3rd sperm-washing. Of oocytes cultured with sperm which were repeatedly washed with heparin and high pH, 52% (57/110) were cleaved over 2 cell stage. However, percent of oocytes parthenogenetically divided was 5%(2 /42).

• Journal of the Korean Society of Visualization
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• 제18권2호
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• pp.51-58
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• 2020

Research on shock structures of supersonic jet through visualization experiments in low-pressure environment have not been actively conducted. Therefore, in this study, shock waves and supersonic jets were analyzed and compared by numerical analysis and Schlieren technique at low-pressure. Schlieren technique is commonly used to visualize the shock waves generated by density gradient as interferometric methods. Pressure ratio of entrance and ambient was set around 4 to observe moderate under-expanded jet. For validation of experimental and numerical results, the shock structure and frequency were compared. In the case of ST and C nozzle, the results were shown that the difference of shock cell distance was within 10%. The Mach number gradually decreased due to energy reduction, and the error rate was within 7%. D nozzle was not fitted to be observing the shock structure. Because the interface between rarefaction fan and supersonic jet was ambiguous and oscillating phemenoma occurred at end of jet, the supersonic jet in low ambient pressure was observed and analyzed.

• Korean Journal of Veterinary Service
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• 제40권3호
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• pp.161-168
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• 2017

Caprine arthritis encephalitis (CAE) virus is a causative agent of caprine arthritis-encephalitis. In our previous study we reported a prevalence of CAE. In this study, we described the further detailed pathological features of CAE and examined the detection of virus by in situ hybridization (ISH). Histopathologically, interstitial pneumonia and bronchopneumonia in lung, focal inflammation in mammary glands, perivascular cuffing in brain, arthritis, and focal necrosis, mild steatosis, inflammatory cell infiltration of liver were noted. CAEV proviral-DNA was identified by nested polymerase chain reaction (PCR) in blood cells, brain, synovial fluid, and lymph node. Confirmation by nested PCR involved amplification of a 296 bp ($1^{st}$ PCR) and 185 bp ($2^{nd}$ PCR) fragments corresponding to a conserved region on the gag gene of CAEV. Positive ISH signals were detected in the brain and liver. In conclusion, significant histopathological findings included parenchymal infection in various organs, including the lung, liver, brain, joint, and mammary gland were noted in the CAEV infected dairy goat. ISH can help confirm the diagnosis of CAE in formalin-fixed samples.

• Fisheries and Aquatic Sciences
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• 제1권2호
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• pp.250-254
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• 1998

Harmful micro algae isolated from Korean coastal waters, were tested with FITC-conjugated lectins and observed by epifluorescent microscopy to distinguish each other. Strain-specific sugar composition at the cell surface was suggested by the affinity of lectins to different microalgae. The micro algae Cochlodinium polykrikoides (CP-1) and Gymnodinium $A_3\;(GA_{3-1}\;1)$, are morphologically similar, but exhibited different binding activity with the lectins ECA, HPA and WGA. In Peridiniales, the micro alga Alexandrium tamarense (AT) bound HPA and WGA, but Scrippsiella trochoidea (ST-1) did not bind those lectins. Three species of Prorocentrum also exhibited different binding specificity with HPA, PHA and SBA. A non­toxic Korean isolate of Heterosigma akashiwo (HA-2) bound ConA, PEA and UEA. These results suggest that lectins are useful in discriminating morphologically similar species, as well as different species or strains within the same genus.

• Korean Journal of Veterinary Research
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• 제57권1호
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• pp.43-45
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• 2017

This study investigated changes in certain blood parameters in calves and pigs after foot-and-mouth disease (FMD) vaccination. In this study, five calves and five pigs were selected from groups of 10 calves and pigs, respectively, and were vaccinated with an FMD vaccine. The remaining animals formed two non-treatment control groups. Blood samples were collected from all animals on the 1st, 3rd, 5th, and 7th days post-vaccination. In the FMD-vaccinated calves and pigs on day 7 post-vaccination, white blood cell counts, blood urea nitrogen levels, and alanine aminotransferase and aspartate aminotransferase activities were higher than those in the respective controls. The present data suggested that the certain hemato-biochemical parameters on cattle and pigs were meaningfully changed between before and after FMD vaccination.

• The KIPS Transactions:PartC
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• 제9C권6호
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• pp.927-934
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• 2002

In order to provide various multimedia services in a wireless network, the call admission control for wireless channels should be resolved at the time of call setup and handoff by moving mobile terminal. In this paper. we propose a reliable DCAC( Distributed Call Admission Control)scheme using virtual cluster concept. The proposed DCAC scheme considers the state of $1^{st}$ and $2^{nd}$ adjacent cells to provide a reliable call handling. The proposed scheme is analyzed by simulations and mathematical methods.

• Journal of Electrical Engineering and Technology
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• 제7권2호
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• pp.207-211
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• 2012

Spinel-$Li_4Ti_5O_{12}$ was successfully synthesized by a solid-phase method at 800, 850, and $900^{\circ}C$ according to the $Li_4Ti_5O_{12}$ cubic spinel phase structure. To achieve higher EDLC energy density with the $Li_4Ti_5O_{12}$, the negative electrode of the hybrid supercapacitor was studied in this work. The electrochemical performances of the hybrid supercapacitor and EDLC were characterized by constant current discharge curves, c-rate, and cycle performance testing. The capacitance (1st cycle) of the hybrid supercapacitor and EDLC was 209 and 109 F, respectively, which is higher than EDLC. The capacitance of the hybrid supercapacitor decreases from 209 F to 101 F after 20 cycles when discharged at several specific current densities ranging from 1 to 10 A. In contrast, capacitance of the EDLC hardly decreases after 20 cycles. Results show that hybrid supercapacitor benefits from the high rate capability of supercapacitor and high capacity of the battery. Findings also prove that the hybrid supercapacitor is an energy storage device where the supercapacitor and the Li ion secondary battery coexist in one cell system.

• Journal of Plant Biotechnology
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• 제29권3호
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• pp.145-150
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• 2002

Biotechnology in the 21st century will be driven by three emerging technologies: genomics, high-throughput biology, and bioinformatics. These technologies are complementary to one another. A large number of economically important crops are currently subjected to whole genome sequencing. Functional genomics for determining the functions of the genes comprising the given plant genome is under progress by using various means including phenotyping data from transgenic mutants, gene expression profiling data from DNA microarrays, and metabolic profiling data from LC/mass analysis. The aim of plant molecular breeding is shifting from introducing agronomic traits such as herbicide and insect resistance to introducing quality traits such as healthful oils and proteins, which will lead to improved and nutritional food and feed products. Plant molecular breeding is also expected to aim to develop crops for producing human therapeutic and industrial proteins.