• Applied Microscopy
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• v.26 no.2
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• pp.235-241
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• 1996

Amophization and decomposition behaviour in $Mg_{62}Cu_{26}Y_{12}$ alloy prepared by melt spinning method and wedge type metal mold casting method have been investigated by a detailed transmission electron microscopy. Amorphous phase has formed in melt-spun ribbon. In the case of the wedge type specimen, however, the amorphous phase has formed only around the tip area within about 2 mm thickness. The remaining part of the wedge type specimen consists of crystalline phases, $Mg_{2}Cu\;and\;Cu_{2}Y$. The supercooling for crystallization behaviour of the amorphous $Mg_{62}Cu_{26}Y_{12}$ alloy, ${\Delta}T_x$ has been measured to be about 60 K. Such a large undercooling of the crystallization bahaviour enables formation of the amorphous phase in the $Mg_{62}Cu_{26}Y_{12}$ alloy under the cooling rate of $10^{2}K/s$. The amorphous $Mg_{62}Cu_{26}Y_{12}$ has decomposed into crystalline phases, $Mg_{2}Cu\;and\;Cu_{2}Y$ after heat treatment at $170^{\circ}C\;and\;250^{\circ}C$.

• KOREAN POULTRY JOURNAL
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• v.3 no.12 s.26
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• pp.55-62
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• 1971

• Fashion Information and Technology
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• v.12
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• pp.55-62
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• 2015

• Journal of applied mathematics & informatics
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• v.2 no.1
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• pp.33-40
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• 1995

Entropy loss is derived by the scale parameter of Rayleigh distribution. Under this entropy loss we obtain the best invariant estimators and the Bayes estimators of the scale parameter. Also we compare MLE with the proposed estimators.

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.62-62
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• 2003

• Journal of the Korean Ceramic Society
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• v.41 no.12 s.271
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• pp.921-928
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• 2004

Calcium phosphate powders have been prepared by using $Ca(OH)_2\;and\;H_{3}PO_4$ solution under various conditions such as pH, calcination temperature, and reaction time. ${\beta}-TCP({\beta}-tricalcium phosphate)$and HAp(hydroxyapatite) were synthesized at pH=5.21 and pH > 7.62, respectively. From XRD results, $Ca(OH)_2\;and\;H_{3}PO_4$ solution reacted quickly to form HAp, which was structurally stable up to 16h. Calcination temperature having good crystallinity is revealed to be at $1200^{\circ}C$. SEM analysis showed that ${\beta}-TCP$ and HAp with needle type were synthesized at pH 5.21 and pH 7.62, respectively. However, at pH 9.16, tiny and homogeneous HAp having sphere was prepared and rearranged to show needle morphology. HAp synthesized at pH 9.16 was utilized as bonechina body and calcined. The sample was analyzed its crystallinity, water absorbtion, color, and shape to check physical properties.

• Biomedical Science Letters
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• v.19 no.2
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• pp.164-167
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• 2013

Osteoclasts are originated from hemopoietic progenitors of the monocyte/macrophage lineage and resorb mineralized tissues. Elevated osteoclast numbers and activity result in bone disease such as osteoporosis, Paget's disease, and tumor osteolysis. In order to identify the genes that are involved in osteoclast differentiation, microarray was performed after treated with RANKL for 12 h and 24 h in osteoclast precursors. The genes that changed by RANKL treatment were grouped by biological process or molecular function. Among them, the number of genes involved in signal transduction and nucleic acid binding was 6065 and 3066, respectively. When analyzed the number of genes changed more than 1.5 fold in the cells treated with RANKL for 12 h or 24 h compared to when RANKL was not treated, 83 and 62 genes were up-regulated; 56 and 62 genes were downregulated, respectively. To verify the microarray results, real-time RT-PCR for Cxcl1 and Slfn1genes that have not been reported yet related to osteoclast differentiation, as well as Ccl2 gene associated with osteoclast differentiation were carried out. Both experiments showed a similar result of more than 1.5 fold induction of these genes by RANKL treatment. These results suggest the possibility that Cxcl1 and Slfn1 may associate with osteoclastogenesis and provide that microarray is a useful tool to analyze the profile of genes changed during osteoclast differentiation by RANKL. Moreover, this gene profile contributes to understand the regulatory mechanisms involved in osteoclast differentiation and the pathogenesis, thus developing therapeutics of bone diseases such as osteoporosis.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1638-1644
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• 2001

The objective of this research was to evaluate alternative treatments for the best extraction condition for collagen from chicken feet. Various properties such as chemical composition, amino acid, pH, swelling percentage, yield and pure collagen, collagen loss, color (Hunter L, a and b) and electrophoresis of collagen from chicken feet treated by 5% acids (acetic acid, citric acid. hydrochloric acid and lactic acid) and soaking times (12, 24, 36 and 48 h) were evaluated. The crude protein, fat, ash and moisture contents of chicken feet was 17.42, 12.04, 5.98 and 62.05%, respectively. Amino acid composition of collagen from chicken feet indicated that the protein of collagen was markedly hydrolized by the hydrochloric acid treatment. The result of electrophoresis also supported this phenomenon. Both the swelling percentage of lactic acid and citric acid treatments were significantly higher than that of acetic acid and HC1 treatment. The pH of the acid treatments ranged from 2.43-3.62. According to the result of yield, pure collagen and loss of collagen, the best condition of extracting collagen from chicken feet was soaked in 5% lactic acid for 36 h. However, a brighter yellow color of collagen from all treatments was observed with a longer soaking time.

• Animal cells and systems
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• v.3 no.3
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• pp.295-301
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• 1999

The nucleotide sequence of a 447 base pair fragment in the mitochondrial cytochrome b gene and the complete sequence of the mitochondrial 12S ribosomal RNA gene, 938 bp, were analyzed to infer inter- and intraspecific genetic relationships of Hyla japonica and H. suweonensis from Korea and H, japonica from Japan. In the mitochondrial cytochrome b gene, genetic differentiation among H. japonica populations were 9.62% and 15.66% between H. japonica and H. suweonensis. Based on the Tamura-Nei distance, the level of sequence divergence ranged from 0.45% to 2.75% within Korean H. japonica, while 8.31%-8.87% between Korean and Japanese H. japonica and 11.51%-12.46% between H. japonica and H. suweonensis. In the neigh-bor-joining tree, Korean populations of H. japonica were clustered first at 2.22% and followed by Japanese H. japonica and H. suweonensis at 8.51% and 12.29%, respectively. In mitochondrial 12S rRNA gene, genetic differentiation between H. japonica and H. suweonensis nras 7.17% (68 bp) including 7 gaps. Based on Tamura-Nei distance, the level of sequence divergence ranged 3.53% between Korean and Japanese H. japonica and from 4.93% to 5.41% between H. japonica and H. suweonensis. Phenogram pattern of the 12S rRNA gene sequence corresponded with that of the mitochondrial cytochrome b gene.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.111-122
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• 1997

H-reflex is a kind of late respons which can be used for the proximal nerve conduction study. Also it is a useful and widely used nerve conduction technique es to look electrically at the monosynaptic reflex. Although recordable from all muscles theoretically, H-reflexes are most commonly recorded from the calf muscles following stimulation of the tibial nerve in the popliteal fossa. But in this study, We tried to establish the normal data and to evaluate the significance of the H-reflex study in cervical radiculopathy. H-reflexes were recorded from flexor carpi radialis (FCR) muscle, extensor carpi radialis (ECR) muscle, brachioradialis (BR) muscle, and abductor digiti minimi (ADM) muscle in 31 normal adults (62 cases) and 12 patients with cervical radiculopathy. The mean values of H-reflex latency in normal control group were $16.16{\pm}1.65$ msec in FCR; $15.99{\pm}1.25$ msec in ECR; $16.47{\pm}1.59$ msec in BR; $24.46{\pm}1.42$ msec in ADM. And the mean values of side to side difference of H-reflex latency were $0.47{\pm}0.48$ msec in FCR; $0.68{\pm}0.72$ msec in ECR; $0.63{\pm}0.43$ msec in BR; $22.31{\pm}1.24$ msec in ADM. Mean values of side to side differences of interlatency time were $0.49{\pm}0.47$ msec in FCR; $0.73{\pm}0.62$ msec in ECR; $0.79{\pm}0.71$ msec in BR; $0.69{\pm}0.44$ msec in ADM. Also, there were no significant differences in H-reflex latency between right and left side. H-reflex tests in patient group with cervical radiculopathy revealed abnormal findings in 11 out of 12 patients. These results suggest that H-reflex in the upper extremity would be helpful in the diagnosis of the cervical radiculopathy.