• Food Science and Biotechnology
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• 제16권5호
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• pp.832-835
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• 2007

Moisture content of normal, waxy, and high amylose com starches was adjusted to 10-35%, and irradiated in a microwave oven. The effect of microwave irradiation on the crystalline structure of starch was measured by using a differential scanning calorimetry (DSC), and X-ray diffractometry. Pasting viscosity profile was also determined by using a rapid viscoanalyzer (RVA). For all the 3 types of starches tested, the rate of temperature increase by the microwave irradiation was faster and more rapidly reached the maximum temperature of the pressure bomb ($120^{\circ}C$) when the moisture content was higher. X-ray diffraction and DSC data revealed that the microwave irradiated starch underwent partial disruption of crystalline structure. RVA studies showed that the irradiation caused significant reductions in maximal viscosity and breakdown, whereas pasting temperature was increased. Overall trends revealed that the microwave irradiation on the starch containing limited moisture content (less than 35%) provided the effects similar to the heat moisture treatment. These effects became more significant when the moisture content was higher. Compared to waxy com starch, normal, and high amylose com starches appeared to be more susceptible to the microwave irradiation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.397-398
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• 2008

This paper performed the basic study for fabricating the low level laser therapy apparatus, and one of the goals of this paper was to make this apparatus used handily. The apparatus has been fabricated using the 655nm laser diode and microprocessor unit. The apparatus used a 655 nm laser diode for laser medical therapy and was designed for a pulse width modulation type to increase stimulation effects. And then, each experiment was performed to irradiation group and non-irradiation group for cells. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of cells was verified in irradiation group as compared to non-irradiation group.

• Archives of Pharmacal Research
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• 제27권10호
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• pp.1060-1064
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• 2004

Although many studies have been performed to elucidate the molecular consequences of ultraviolet irradiation, little is known about the effect of natural products. Ultraviolet irradiation is widely considered to be an environmental stress. Here we investigated the effect of 3,23-dihydroxy- 20(29)-lupen-27-oic acid on the regulation of MMP-1 and type 1 procollagen in Ultraviolet irradiation of cultured old age human dermal fibroblasts. 3, 23-dihydroxy-20(29)-lupen-27- oic acid was isolated from Tiarella polyphylla D. Don (Saxifragaceae). Among them, 3, 23- dihydroxy-20(29)-lupen-27-oic acid induced the regulation of Type 1- procollagen and reduced the regulation of MMP-1 at the protein levels in a dose-dependent manner by ultraviolet irradiation. Taken together, our results suggest that 3, 23-dihydroxy-20(29)-lupen-27-oic acid plays an important role in the induction of Type 1-procollagen and reduction of MMP-1 by ultraviolet irradiation in old age human dermal fibroblasts.

• Nuclear Engineering and Technology
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• 제49권7호
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• pp.1472-1482
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• 2017

Zirconium alloy cladding tube specimens were irradiated at $380^{\circ}C$ up to a fast neutron fluence of $7.5{\times}10^{24}n/m^2$ in a research reactor to investigate the effect of neutron irradiation on hydride reorientation and mechanical property degradation. Cool-down tests from $400^{\circ}C$ to $200^{\circ}C$ under 150 MPa tensile hoop stress were performed. These tests indicate that the irradiated specimens generated a smaller radial hydride fraction than did the unirradiated specimens and that higher hydrogen content generated a smaller radial hydride fraction. The irradiated specimens of 500 ppm-H showed smaller ultimate tensile strength and plastic strain than those characteristics of the 250 ppm-H specimens. This mechanical property degradation caused by neutron irradiation can be explained by tensile hoop stress-induced microcrack formation on the hydrides in the irradiation-damaged matrix and subsequent microcrack propagation along the hydrides and/or through the matrix.

• BMB Reports
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• 제33권2호
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• pp.133-137
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• 2000

To elucidate the effect of oxygen radicals on the molecular properties of proteins, the secondary and tertiary structure and molecular weight size of BSA and ${\beta}$-lactoglobulin were examined after irradiation of proteins at various doses. Gamma-irradiation of protein solutions caused the disruption of the ordered structure of protein molecules as well as degradation, cross-linking, and aggregation of the polypeptide chains. As a model system, BSA and ${\beta}$-lactoglobulin were used as a typical ${\alpha}$-helical and a ${\beta}$-sheet structure protein, respectively. A circular dichroism study showed that the increase of radiation decreased the ordered structure of proteins with a concurrent increase of aperiodic structure content. Fluorescence spectroscopy indicated that irradiation quenched the emission intensity excited at 280 nm. SDS-PAGE and a gel permeation chromatography study indicated that radiation caused initial fragmentation of proteins resulting in a subsequent aggregation due to cross-linking of protein molecules.

• 한국가금학회지
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• 제21권1호
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• pp.49-56
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• 1994

Food irradiation is beginning to provide a safe, effective, and economical alternative treatment for many food products, especially for the raw food of animal origin. The historical background and wholesomeness of food irradiation were examined. The application and effect of the process were investigated. The cost and benefit of the irradiated poultry meat were evaluated. The effect of irradiation on the poultry meat, poultry products, and microorganisms were reviewed. With the safety of irradiated poultry meat and poultry products established, the future of the process is promissing.

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2001년도 추계학술대회 및 정기총회
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• pp.22-22
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• 2001

We performed this study to determine the effect of Panax ginseng and its fractions on jejunal crypt survival, endogenous spleen colony formation, and apoptosis in jejunal crypt cells of mice irradiated with high and low dose of $\gamma$-irradiation. The radioprotective effect of ginseng was compared with the effect of diethyldithiocarbamate (DDC). Ginseng administration before irradiation protected the jejunal crypts (p<0.005), increased the formation of endogenous spleen colony (p<0.005) and reduced the frequency of radiation-induced apoptosis (p<0.005). (omitted)

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.423-423
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• 2009

Currently, lasers are one of the most popular light sources in use for medical treatment. Many studies on low power lasers are being done in cell culture or through animal tests and most report different findings, making it difficult to verify their true effects. There are shifts in trends of studies from laser and LED that are expensive and generate heat problem to LED that are economically effective and safe. Its near infrared rays can penetrate deep into skin or muscle, up to 23 cm, without causing thermal damage or impairing neighboring tissues. This study verified the performance and effectiveness of an LED irradiator that was designed to emit similar wavelengths to that of a laser and thus could be used instead of a low level laser therapy in experiments on animals. And then, each experiment was performed to irradiation group and non-irradiation group for NTacSam:SD tissue cells. MIT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of NTacSam:SD tissue cells was verified in irradiation group as compared to non-irradiation group. The fact that specific wavelength irradiation has an effect on cell vitality and proliferation is known through this study.

• 한국식품영양과학회지
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• 제31권2호
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• pp.246-250
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• 2002

감마선 조사가 왕겨, 미강, 맥강의 항산화능에 미치는 영향을 조사하기 위하여 4.2 kGy/h의 속도로 각각 5, 10, 15, 20 kGy를 조산한 후, 메탄올 추출물을 제조하여 항산화능의 변화를 측정하였다. 감마선을 조사하지 않은 시료의 총 페놀함량을 측정한 결과, 왕겨가 0.873 mM, 미강이 0.643 mM, 맥강이 0.377 mM로 측정되었으며, 감마선 조사에 따른 총 페놀 함량은 조사선량에 상관없이 일정하게 유지되었다. 전자공여능의 측정결과 감마선을 조사하지 않은 왕겨, 미강, 맥강에서 모두 비슷한 활성을 보였으며, 감마선을 조사한 경우에도 모든 시료에서 조사선량에 따른 유의적인 변화를 나타내지 않았다. TBARS분석에서는 감마선을 조사하지 않은 왕겨와 미강 추출물이 맥강 추출물보다 지질 과산화 억제력이 높았으며, 감마선 조사시에도 왕겨와 미강은 활성이 유지 또는 보유되었으나 맥강은 조사선량이 높을수록 지질의 산화 억제력이 상당히 감소되었다. 따라서 왕겨, 미강, 맥강의 페놀성분과 전자공여능에 관여하는 성분이 감마선에 매우 안정하며, 지질 과산화 억제능에 관여하는 성분은 왕겨와 미강의 경우에는 감마선에 안정하지만 맥강의 경우 불안정하였다.

• 한국식품저장유통학회지
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• 제6권3호
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• pp.286-291
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• 1999

본 연구는 감마선 조사 시기, 강도 및 조사 후 보존제 처리가 절화장미와 국화의 수명에 미치는 영향을 알기 위하여 시행하였던 바 얻은 결과는 다음과 같았다. 절화장미의 경우 감마선 조사 강도가 0.5 KGy 까지는 절화품질에 미치는 영향이 적다고 할 수 있었으나, 이 보다 강한 조사구에서는 절화장미의 품질이 매우 악화되었으며, 조사 후 설탕용액에 침지한 것은 0.75 KGy 처리구까지 절화의 품질 유지효과가 인정되었다. 조사 후 절화보존제 침지 처리의 효과 실험에서는 2% sucrose, 0.2% silver nitrate, 1.0% Crysal 처리구에서 각각 선도 유지 효과가 어느 정도 인정되었으나, silver nitrate 처리구에서는 절화기부의 갈변부패가 매우 심한 것에서 절화수명의 연장에는 별 효과가 없었음을 알 수 있었다. 절화국화의 경우에는 감마선 조사 강도가 강해질수록 관산가치가 급격히 저하되었으며, 2.0KGy의 강도로 조사한 감마선 처리구에서는 증류수 및 HQS에 침지한 절화를 제외하고 다른 절화 보존제 처리구에서는 절화 수명이 급격히 저하되었다. 절화 보존제의 처리효과 중에 설탕용액의 침지 효과가 제일 우수하였는데, 감마선 무조사구에서 절화가 완전히 시들 때까지도 어느 정도 꽃을 관상 할 수 있을 정도로 절화수명은 유지되었다.