• The Korea Journal of Herbology
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• v.26 no.4
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• pp.125-132
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• 2011

Objectives : An aim of study is to investigate effects of curculiginis rhizoma in vitro (factor Xa (FXa) inhibitor assay, prothrombinase assay, prothrombin time (PT) assay, activated partial thromboplastin time (aPTT) assay) and in vivo experiment (blood clotting time, thromboxane B2 content assay in serum and weight of thrombus by AV-shunt rat model). Methods : We gained a human serum and used serum in vitro study such as factor X activity (FXa) inhibition, prothrombinase inhibition, prothrombin time (PT) and activated partial thromboplastin time. Fifteen SD rats were divided into three groups (intact control group and two experimental group treated with extract of Curculiginis Rhizoma(ECR)). Rats were orally administrated DW (intact control group), 600 mg/kg concertration of ECR and 200 mg/kg concertration of ECR. After one hour, we anesthetized rats and made arteriovenous (AV) shunt rat models to study weights of thrombus, took a hole blood to study content of thromboxane B2 and blood clotting time. Results : In vitro, ECR increased a inhibitory activity of FXa, prothrombinase and aPTT compared than intact control group. Especially ECR made significant increase of FXa and prothrombinase inhibitory activity (p<0.05, p<0.01). And PT were increased in ECR control group compared with intact control group. In vivo, a blood clotting time of experiment group treated with ECR 600 mg/kg were significantly increased compared with that of intact control group (p<0.05) and content of thromboxane B2 was significantly decreased in group treated with ECR 600 mg/kg in seum. The weight of thrombus were significantly reduced in group treated with ECR 600 mg/kg compared with intact control group (p<0.05). But in vivo experiment study, those of group treated with ECR 200 mg/kg were reduced compared with those of intact control group without statistical significance. Conclusions : ECR has a antithromboic activity in internal course with inhibitory activity of FXa and prothrombinase in vitro, it required to research more study for effective compounds.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.4
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• pp.166-173
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• 2021

The rutile phase of TiO₂ forms a stable phase at high temperatures compared to anatase phase, but the stable temperature range of anatase changes depending on the synthesis conditions. In this study, nano-sized TiO₂ was synthesized by the Sol-gel method using TiOSO₄ and a mixed solvent of ethanol and distilled water, and the phase change of anatase and rutile according to pH and heat treatment temperature was investigated. Changes in the ratio of anatase and rutile were observed by changing the pH (3, 5, 7, 9) and heat treatment temperature (500, 600, 700, 800, 900℃) conditions of the prepared TiO₂. As a result of observing these changes through XRD and FE-SEM analysis, anatase TiO₂ at 500℃ and rutile TiO₂ at 900℃ were observed. According to the pH, at these intermediate temperatures of 600, 700 and 800℃, the ratio of anatase and rutile changes. At 700℃, it was concluded that pH = 3~5 had a larger ratio of anatase TiO₂, and pH = 7~9 had a larger ratio of rutile TiO₂.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.275-281
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• 1995

From the plasmid pYA300 carring a CMCase of Rhizobium fredii USDA193 plasmid was subcloned into pBluescript II KS(+)/pBluescript II SK(+) vectors and designated pYA500 and pYA600, respectively. Escherchia coli cells transformed with pYA500 porduced the CMCase more than with pYA600. The orientation of the cloned fragment in pBluescript vector had the effect on gene expression in E. coli background. When the 1.7 kb CMCase gene fragment of R. fredii USDA193 was hybridized to EcoRI-digested total DNA from R. meliloti and R. fredii USDA 191 the unique bands hybridized respectively, indicating that some genetic diversity exists in the EcoRI restriction enzyme site for CMCase gene in Rhizobium strains. The optimum pH of enzyme activity was 7 and the optimum temperature of that was nearly 37$\circ$C. The cellulase-minus derivatives of pYA500 were constructed by Tn5 insertional mutation. Among 6000 transconjugants, two mutant plasmids (designated pYA500::Tn5a and pYA500::Tn5b) were detected from the cellulase- negative transconjugants. The product of CMCase gene was analyzed by one dimensional SDS- PAGE of the cell extracts. About 45 kDa protein was considered to be a product of CMCase gene.

• Journal of the Korean institute of surface engineering
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• v.54 no.4
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• pp.171-177
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• 2021

This paper is concerned with the surface hardness measurement of NiP-coated AA7050 using different loads from 10 to 100 g. The surface hardness was observed to increase from 180 to 600 H_v with increasing NiP layer thickness, depending on the load applied for indentation. When NiP coating thickness is thinner than 2 ㎛, the surface hardness of NiP-coated AA7050 was mainly determined by AA7050 substrate, while it was significantly increased by NiP coating layer when NiP coating thickness is thicker than 2 ㎛. Hardness of AA7050 substrate itself was not dependent on the applied load but the hardness of NiP-coated AA7050 was largely influenced by the load applied for indentation. The largest difference of hardness between 10 g and 100g of applied loads, was obtained at the NiP thickness of about 8 ㎛ above which the measured hardness at 10 g reached a maximum value of about 600 H_v. It was also observed that indentation-induced plastic deformation next to the indented zone occurs when NiP layer is 5.64 times thicker than the depth of impression formed by indentation.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.2
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• pp.75-80
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• 2012

Papillary thyroid carcinoma (PTC) is the most common thyroid cancer, accounting for 95% or more of malignancies in Korea. Recently, many thyroid cancers have been detected owing to the widespread use of ultrasonography in health surveillance. The objective of this study was to evaluate the association of known prognostic factors with the $BRAF^{V600E}$ mutation and its association features in Korean patients with papillary thyroid carcinomas. The $BRAF^{V600E}$ mutation was detected in 69.1% (256 of 370) of PTC cases. In univariate analysis, the $BRAF^{V600E}$ mutation was significantly associated with tumor size (p < 0.05) and sex. However, it was not significantly associated with other established risk factors, such as age, extrathyroidal extension, and lymph node metastasis. This finding supports the idea that the BRAF mutation plays a role in the early stage of PTC development. This relationship deserves further investigation to clarify whether $BRAF^{V600E}$ is a useful risk factor or prognostic marker for PTC.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1664-1670
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• 1991

For kinematically redundant manipulators, conventional dynamic control methods of local torque optimization showed the instability which resulted in physically unachievable torque requirements. In order to guarantee stability of the null space vector method which resolves redundancy at the acceleration level, Maciejewski[1] analyzed the kinetic behavior of homogeneous solution component and proposed the condition to identify regions of stability and instability for this method. 'In this paper, a modified null space vector method is first presented based on the Maciejewski's condition which is a function of a manipulator's configuration. Secondly, a new control method which is based on the concept of aspects is proposed. It was shown by computer simulations that the modified null space vector method and the proposed method have a common property that a preferred aspect is preserved during the execution of a task. It was also illustrated that both methods demonstrate a drastic reduction of torque loadings at the joints in the tracking motion of a long trajectory when compared with the null space vector method, and thus guarantee the stability of joint torque.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.258-263
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• 1994

Ohjuksan has been used for the treatment of cold and pantalgia in traditional medicine. The anti-inflammatory activity of the aqueous extract from Ohjuksan (OJSE) was investigated utilizing acetic acid-induced edema and adjuvant arthritis in rats. The effects of this agent on acute toxicity and acetic acid-induced writhing syndrome in mice were also examined. OJSE did not showed acute toxicity at 2400mg/kg (p.o.) and 1200mg/kg(i.p.) body weight. It was also showed to have significant analgesic action on the writhing syndrome in mice induced by 0.7% acetic acid at 300,600mg/kg body weight. It showed anti-inflammatory activity in 5% acetic acid-induced edema and adjuvant arthritis with oral administration in rats and exhibited significant preventive effect on edema at 300 and 600mg/kg(p<0.01). In the method of adjuvant arthritis, orally administered for 19 days, it inhibited the hind paw edema in rats with 300 and 600 mg/kg body weight from 5 th day to 19th day. These results suggest that OJSE had analgesic and anti-inflammatory action.

• Korean Journal of Metals and Materials
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• v.49 no.9
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• pp.699-707
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• 2011

P122 steel, with a composition of Fe-10.57%Cr-1.79%W-0.96Cu-0.59Mn was arc-welded and oxidized between $600^{\circ}C$ and $800^{\circ}C$ in air for up to 6 months. The oxidation rates increased in the order of the base metal, weld metal, and heat-affected zone (HAZ), depending on the microstructure. The scale morphologies of the base metal, weld metal, and HAZ were similar because it was determined mainly by the alloy chemistry. The scale consisted primarily of a thin $Fe_2O_3$ layer at $600^{\circ}C$ and $700^{\circ}C$ and an outer $Fe_2O_3$ layer and an inner ($Fe_2O_3$, $FeCr_2O_4$)-mixed layer at $800^{\circ}C$. The microstructural changes resulting from heating between $600^{\circ}C$ and $800^{\circ}C$ coarsened the carbide precipitates, secondary Laves phases, and subgrain boundaries in the matrix, resulting in softening of the base metal, weld metal, and HAZ.

• Journal of the Korean Wood Science and Technology
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• v.37 no.1
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• pp.87-93
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• 2009

Properties and chemical bonding of wood charcoal were investigated to understand the chemistry occurring in wood carbonization. From the pH changes of wood charcoal, it is revealed that it becomes acidic to weakly basic for charcoal carbonized at about $300^{\circ}C$, whereas it turns to basic at higher carbonization temperature higher than $600^{\circ}C$. Also, the ratio of carbon atoms in the charcoal was increased with increasing the carbonization temperature, while those of oxygen and hydrogen atoms. This tendency was significant when the carbonization temperature was increased up to $600^{\circ}C$ and the ratio changes of the atoms became stable at above $600^{\circ}C$. In the changes of chemical bonding, the ratio of C-C bonding was increased and those of C-O-H and C-O-R bonding was decreased significantly. It is considered that bondings connected to oxygen atoms tends to be broken, and the ratio of C-C bonding increased. Consequently, it is expected that this change may causes occurrence of new functional groups. In addition to that, it seems to be that the chemical bondings undergo the partial decomposition, formation, and recombination steps, Because ratio of C=O bonding tended to be increased or decreased by increasing the carbonization temperature. This understanding of chemical bond changes in charcoal can be a compensative consideration on the knowledges made only by physical parameters in the properties of micro-pore which has limited to explain the phenomenon. Also, it is considered that this can be treated as a basic knowledge for upgrading and development of use of wood charcoal.

• The Korean Journal of Zoology
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• v.6 no.2
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• pp.11-15
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• 1963

A total of 220 adult male mice (18-20g) of the S.M. strain were divided into ten experimental and control groups. The total-body X-ray irradiation doses used were 50 r, 100r, 200r, 400r, 600r, 800r, 1,000r, 1,200r, 1,400r, and1,600r. The respiratory arrest (mortality) caused by each irradiation doses were observed for 30 days. Relationships between irradiation doses and survival time and percentage of response were examined. From this experiment, a formula was obtained to express the relationship among three factors, which may be presented as follows : {{{{{{{{P= { 10} over { SQRT { 2 pi } } INT _{ - INF }^{ p'} e-{(p'-50)^2 } over {200 }dp···(a) p'=100 LEFT { t^0.3- LEFT ( { { 16.9965} over {D-60 } } RIGHT ) ^{ { 1} over {2.5 } } } / LEFT { LEFT ( { 26372.43} over {D-81.86 } RIGHT ) ^{ { 1} over {2.5 } } -( { { 16.9965} over {D-60 } } RIGHT ) ^{ { 1} over {2.5 } } ···(b) p= { (D-60) t^0.75-16.9965} over {0.2186 t^0.75 +263.55434 }····(c) }} {{{{P= { 10} over { SQRT { 2 pi } } INT _{ - INF }^{ p'} e-{(p'-50)^2 } over {200 }dp···(a) p'=100 LEFT { t^0.3- LEFT ( { { 16.9965} over {D-60 } } RIGHT ) ^{ { 1} over {2.5 } } } / LEFT { LEFT ( { 26372.43} over {D-81.86 } RIGHT ) ^{ { 1} over {2.5 } } -( { { 16.9965} over {D-60 } } RIGHT ) ^{ { 1} over {2.5 } } ···(b) p= { (D-60) t^0.75-16.9965} over {0.2186 t^0.75 +263.55434 }····(c)