• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.4
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• pp.314-317
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• 2009

This paper describes the temperature characteristics of polycrystalline 3C-SiC micro resonators. The $1.2{\mu}m$ and $0.4{\mu}m$ thick polycrystalline 3C-SiC cantilever and doubly clamped beam resonators with $60{\sim}100{\mu}m$ lengths were fabricated using a surface micromachining technique. Polycrystalline 3C-SiC micro resonators were actuated by piezoelectric element and their fundamental resonance was measured by a laser vibrometer in vacuum at temperature range of $25{\sim}200^{\circ}C$. The TCF(Temperature Coefficient of Frequency) of 60, 80 and 100 On long cantilever resonators were -9.79, -7.72 and -8.0 ppm/$^{\circ}C$. On the other hand, TCF of 60, 80 and $100{\mu}m$ long doubly clamped beam resonators were -15.74, -12.55 and -8.35 ppm/$^{\circ}C$. Therefore, polycrystalline 3C-SiC resonators are suitable with RF MEMS devices and bio/chemical sensor applications in harsh environments.

• The Journal of the Korean Society for Microbiology
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• v.35 no.4
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• pp.299-308
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• 2000

Recently developed cDNA microarray or DNA chip technology allows expression monitoring of expression of hundreds and thousands of genes simultaneously and provides a format for identifying genes as well as changes in their activity. In order to search for changes in gene expression after X irradiation in HL60 cells, cDNA microarray technique was done. In this study, expression of 588 human genes (including oncogenes, tumor suppressor genes, cell cycle regulator genes, intracellular signal transduction modulator genes, apoptosis related genes, transcription factor genes, growth factors and receptor genes, cytokine genes, etc) were analyzed. For cDNA microarray analysis mRNAs were extracted from control and 8 Gy-irradiated HL60 cells. As a result the changes in expression of several genes were observed. This alteration of gene expression was confirmed by reverse transcription-polymerase chain reaction. The expression of heat shock 60 KD protein, c-jun, erythroid differentiation factor, CPP32, myeloid cell nuclear differentiation antigen, MAP kinase-activated protein kinase, interleukin-8, monocyte chemotactic peptide 1 and RANTES genes was increased, but the expression of p55CDC gene was decreased after X irradiation.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.45-53
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• 2019

This study observed the effects of the double combination of temperatures-times (2 temperatures: 2 times combination, 2T2T) in sous vide cooking method on the physicochemical properties and collagen solubility (CS) of semitendinosus muscle from cattle and goat as a comparison to common sous vide treatment (1 temperature: 1 time combination, 1T1T). The new invention of sous vide cooking method (2T2T) cooked at the first temperature at $45^{\circ}C$ for 3 h, and the second temperature at $60^{\circ}C$, $65^{\circ}C$, and $70^{\circ}C$ for 3 h, and labeled as N45-60, N45-65, and N45-70, respectively. While, common sous vide treatment (1T1T) were cooked directly for 6 h at $60^{\circ}C$ (T60), $65^{\circ}C$ (T65), and $70^{\circ}C$ (T70). Results revealed that cooking with 2T2T treatment improved the water-holding capacity and reduced the cooking loss of both beef and goat meat. The $L^*$ values have no apparent changes between treatment in beef and goat meat, while $a^*$ values of N45-60 treated goat presented markedly higher values than other treatments but an only slight increase in beef at the same treatment (p>0.05). Again, 2T2T treatment tended to decrease mean shear force (SF) values for beef and goat meat with the lowest SF values recorded at N45-60, and the CS no or less influenced this value. Therefore, the application of innovative sous vides cooking method (2T2T) presented comparable values in the treated beef and goat meat as compared to common sous vide method (1T1T).

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.383-387
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• 1998

This study was undertaken with packed tofu products to serve as a basic source for sanitary control of tofu production by detecting spoilage bacteria in tofu from which are isolated, investigating heat-resistance and growth characteristics of spoilage bacteria. Isolated strains were confirmed as relevant strains in tofu spoilage, and Strain No. Tl, T2 show 92% probability to be Enterobacter amnigenus, and 96% to be Flavobacterium indologenes according to the result of identifYing strains by using Vitek system. Both strains had high viability at $35^{\circ}C$, pH 6.5. In the heat-resistance test of isolated strains, Enterobacter amnigenus Tl was treated for 2 mins, the number remained 56.3% of the initial number at $60^{\circ}C$, 37.8% at $70^{\circ}C$, 34.0% at $80^{\circ}C$ and 22.2% at $90^{\circ}C$, and Flavobacterium indologenes T2 was treated for 2 mins, the number remained 74.8% of the initial number at $60^{\circ}C$, 65.7% at $70^{\circ}C$, 37.8% at $80^{\circ}C$ and 9.3% at 90^{\circ}C$.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.159.2-159.2
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• 2003

Codonopside lc is an active natural compound isolated from the roots of Codonopsis lanceolata (Campanulaceae), a Korean medicinal herb. In the present study, we investigated the in vitro effect of Codonopside 1c on the proliferation and induction of apoptosis in HL-60 human promyelocytic cells. When HL-60 cells were treated with Codonopside 1c, evidence of apoptotic features, including DNA fragmentation, formation of DNA ladder in agarose gel elecrophoresis and increse of annexin V binding, were obtained. (omitted)

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.260-262
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• 2003

In this study, high temperature tensile properties of high tensile strength steels(POSTEN60, POSTEN80) were investigated by elevated temperature tensile test. According toe the results, high temperature tensile strength of POSTEN60 deteriorated slowly to 100$^{\circ}C$. As the temperature went up the tensile strength became better because of blue shortness and it deteriorated radically after reached to the maximum value around 300$^{\circ}C$. For the POSTEN80, high temperature tensile strength deteriorated slowly to 200$^{\circ}C$.As the temperature went up the tensile strength became better and it deteriorated slowly to 600$^{\circ}C$ after reached to the maximum value around 300$^{\circ}C$. Strain of high tensile strength steels at the elevated temperature increased radically after the mercury rose to 600$^{\circ}C$. The strain hardening ratio of POSTEN60 was larger then that of POSTEN80 at the elevated temperature as in the case at the room temperature and it became smaller radically after the mercury rose to 400$^{\circ}C$.

• Journal of Life Science
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• v.10 no.6
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• pp.621-629
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• 2000

Camptothecin (CPT) is an antitumor alkaloid that has been isolated from the Chinese tree, Camptotheca acuminata. The cytotoxicity of CPT has been correlated to its inhibition of DNA topoisomerase (Topo) I by stabilizing drug-enzyme-DNA “cleavable complex" resulting in DNA single-strand breaks and DNA-protein crosslinks. This studies were designed to elucidate whether CPT regulates Topo I mediated by CPT in DNAs containing c-myc protooncogene. We have conducted experiments on Topo I purification, pUC-MYC I cloning and Topo I assay using electrophoresis, quantitative RT-PCR and Northern blotting techniques. CPT ingibited the relaxation activity of Topo I in pUC19 DNA at various concentrations (1-1000 $\mu$M), while it enhanced the cleavage of Topo I in the pUC-MYC I by forming a cleavable complex at relatively high concentrations (100-1000 $\mu$M). In HL-60 cells treated with CPT, the expression of c-myc gene was decreased over that in the control group with no changes in the expression of Topo I mRNA. Our results suggest that Topo I is the target of CPT cytotoxicity but it does not affect Topo I extression, and the suppression of c-myc mRNA expression by CPT is due to c-myc damage resulted from formation of a cleavable complex with CPT. CPT.

• Journal of Welding and Joining
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• v.22 no.4
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• pp.50-58
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• 2004

In this study, high temperature tensile properties of high strength steels(POSTEN60, POSTEN80) were investigated. The three-dimensional thermal elastic-plastic analyses were conducted to investigate the characteristics of welding residual stresses in welds of high strength steels on the basis of thermal and mechanical properites at high temperature obtained from the experiment. According to the results, high temperature tensile strength of POSTEN60 steel deteriorated slowly to 10$0^{\circ}C$. As the temperature went up, the tensile strength became better because of blue shortness, and it deteriorated radically after reaching to the maximum value around 30$0^{\circ}C$. For the POSTEN80 steel, high temperature tensile strength deteriorated slowly to 20$0^{\circ}C$. As the temperature went up the tensile strength became better and it deteriorated slowly to $600^{\circ}C$ after reached to the maximum value around 30$0^{\circ}C$. Strain of high strength steels at the elevated temperature increased radically after the mercury rose to $600^{\circ}C$. The strain hardening ratio of POSTEN60 steel was larger then that of POSTEN80 steel at the elevated temperature as in the case at the room temperature and it became smaller radically after the mercury rose to 40$0^{\circ}C$. And, in the welding of high strength steels, increasing tensile strength of the steel (POSTEN60

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.289-293
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• 1989

During soaking of soybeans in water at $4^{\circ}C{\sim}98^{\circ}C$, the volume gain of soybeans held a linear relation with the square root of soaking time regardless of soaking temperatures and showed a highly positive correlation with weight gain, which indicated that the volume increase of soybeans was basically due to the diffusion of water. The activation energies for the volume increase were changed at $40^{\circ}C$. The log time to reach a fixed moisture content showed a linear relation with the soaking temperature during soaking of soybeans at $4^{\circ}C-60^{\circ}C$. The z-value to reach 50% hydration was $50^{\circ}C-55^{\circ}C$.