• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.3-5
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• 1998

The interest in the use of borate crystals in ultraviolet(UV) nonlinear optics(NLO) has increased because all solid-stste UV lasers obtained with NLO are in highly demand. Much effort has been spent on developing borates series, such as{{{{ { beta -BaB }_{2 } {O }_{4 }(BBO), {LiB }_{ 3}{O }_{5 }(LBO)}}}} and{{{{{ CsKiB}_{6 }{O }_{10 }(CLBO)}}}} in this decade. Recently another new borate crystals, {{{{{ YCa}_{4 }O({BO }_{3 })_{3}}}}} and{{{{{Gd }_{x }{Y }_{1-x }{Ca }_{4 }O({BO }_{ 3})({Gd }_{x }{Y }_{1-x }COB)}}}} have been developed by the present authors. Here, the growth and NLO properties of YCOB and {{{{ {Gd }_{ x} {Y }_{ 1-x} }}}}CO B crystal are reported and their properties discussed in relation to those of other nonlinear optical crystals, such as LBO.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2006년도 추계 학술발표회 발표논문집
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• pp.455-457
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• 2006

The effects of UV-B irradiation on the growth and photosynthetic activity were investigated in seedlings of sunflower(Helianthus annuus L.). The first leaves irradiated with UV-B were retarded in growth but simultaneously acquired a remarkably decreased chlorophyll fluorescence ratio compared with the non-irradiated leaves. The Fv/Fm ratio decreased by 13 % compared to the control after 2 d, and was kept to be lower than the control level until 5 d. From the results it is suggested that UV-B radiation may induce reduced biomass production and decrease in photosynthetic rate in sunflower plants.

• 동의생리병리학회지
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• 제25권3호
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• pp.533-539
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• 2011

Sulfuretin is one of the main flavonoids produced by Rhusverniciflua. Sulfuretin has been shown to exhibit many pharmacological activities including anti-oxidant, anti-obesity, anti-inflammatory and anti-mutagenic activities. However, the anti-skin photoaging effects of sulfuretin has not yet been reported. In the present study, we investigated the inhibitory effect of sulfuretin on the expression levels of MMP-1 and -3 in the human dermal fibroblast cells. Western blot analysis and real-time PCR revealed sulfuretin inhibited UVB-induced MMP-1 and -3 expressions in a dose-dependent manner. UVB-induced MAPK/NF-${\kappa}B$/p50 activation and MMP expression were completely blocked by pretreatment of sulfuretin. Taken together, sulfuretin could prevent UVB-induced MMP expressions through inhibition of MAPK/NF-${\kappa}B$/p50 activation.

• 미생물학회지
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• 제24권1호
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• pp.51-56
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• 1986

Eight strains of the bacteria capable of growing on salicylate as the sole carbon source were isolated form soil and river water. Three of these isolates were identified as Acinetobacter calcoaceticus (AcBl), Pseuomonas putida biotype B (PpB2), and P. putida biotype A (PpB3). Effects of temperature, pH and C source concentration on biodegradation of salicylate by PpB3 were wxamined. The optimum conditions were as follows; $30^{\circ}C$ for temperature, 7.0 for pH, and 10mM for C source concentration. Ultraviolet scanning spectrum of the salicylate was measured. The spectrum has two peaks at 225nm and 292nm. The spectra of the culture filtrates indicate that ring degradation of salicylate is accomplished.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1221-1224
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• 2005

The improvement of luminance and luminous efficiency is the one of the most important parts in AC-PDPs. To achieve high luminance and luminous efficiency, high VUV emission efficiency is needed. We measured the emission spectra of the vacuum ultraviolet(VUV) rays in surface discharge AC-PDP with ternary gas mixture of He-Ne-Xe. The influence of He-Ne-Xe gas-mixture ratio on excited $Xe^{\ast}$ resonant atoms and $Xe_2\;^{\ast}$ dimers has been investigated. It is found that luminous efficiency of ternary gas mixture, He-Ne-Xe, is shown to be much higher than that of binary gas mixture of Ne-Xe. For improving discharge luminous efficiency, we have studied VUV emission characteristics of ternary gas mixture, He(50%)-Ne-Xe and He(70%)-Ne-Xe with Xe concentration and filling gas pressure.

• 한국식품영양학회지
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• 제27권5호
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• pp.845-850
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• 2014

In the present study, the effects of extracts from Korean plants on the DNA damage response in HaCaT cells exposed to ultraviolet B (UVB) were investigated. The activity of cells treated for 24 hr with ethanol extracts from Vaccinium spp. (VS), and Vitis vinifera L (VV) alone was similar to that of the non-treated control, but gradually decreased at concentrations above $200{\mu}g/mL$. However, when post-incubation of UVB-exposed cells was carried out for 24 hr in medium containing VS or VV extracts, the cell activity increased in a concentration-dependent manner compared with that in the normal growth medium. The cell viability of UVB-exposed cells also increased when post-incubated in medium containing VS or VV extracts, in a concentration-dependent manner. Nuclear fragmentation analysis showed that post-incubation with VS or VV extracts decreased the UVB-induced apoptosis by about 10 and 13%, respectively, of that in cells post-incubated in growth medium. After 24 hr of post-incubation in medium containing VS or VV extracts, the level of CPD and 8-OHdG decreased in time- and concentration-dependent manners. Overall these results suggest that VS and VV extracts assist the survival of UVB-exposed cells, in accordance with the respective decrease in the levels of UVB-induced DNA damage.

• 한국식품영양학회지
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• 제31권4호
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• pp.495-501
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• 2018

Ultraviolet B (UVB) exposure is a risk factor for skin damage resulting in oxidative stress, inflammation, and cell death. The purpose of this study was to investigate the physicochemical properties of Platycodon grandiflorum (PG) to improve its biological activities using a three-step steaming process. We investigated the protective effects of PG and steamed PG extracts on human dermal fibroblasts (HDFs) against UVB radiation-induced oxidative stress and inflammation as well as the underlying mechanisms. The antioxidant potential of the PG extracts was evaluated by measuring the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging activity. ABTS and DPPH were shown by the 0, 30, and 70% ethanol extracts of 2S-PG and 3S-PG ($IC_{50}$, 28~45 and $27{\sim}30{\mu}g/mL$, respectively). Treatment of UVB-irradiated cells with steamed PG ($25{\sim}400{\mu}g/mL$) did not affect their viability. The streamed PG extract suppressed UVB-induced generation of reactive oxygen species (ROS). In addition, streamed PG extract reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expression in UVB-irradiated HDF, regulating nuclear factor $(NF)-{\kappa}B$ expression. These findings suggest that steamed PG extract may be potentially effective against inflammation associated with UVB-induced oxidation stress.

• Environmental Analysis Health and Toxicology
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• 제20권2호
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• pp.143-151
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• 2005

Exposure of skin to UV-B radiation can cause inflammatory response and immunosuppression. It has been reported that Korean Red Ginseng (KRG) has several pharmacological and physiological effects such as antioxidant, anticancer and improving immune function. In this study, we investigated that topical KRG and KRG + EGb 761 (Ginkgo biloba extract) combination prevented UV-B induced inflammation and inhibition of contact hypersensitivity response. Topical application of KRG, f days prior to or 5 days after exposure to 1MED and 2MED of UV-B, reduced skin thickness compared to non -treated group and resulted in protection against immunosuppression. However, KRG+EGb 761 combination has a little protection against the only 1MED UV-B. In conclusion. Topical application of KRG was more effective than combination in protection against UV-B induced inflammation and immune suppression. Also, we suggest that KRG can provide protection from inflammation and immunosuppression by UV-B radiation.

• Journal of Nutrition and Health
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• 제10권4호
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• pp.24-32
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• 1977

It was attempted in this study to assess the vitamin $B_{1},\;B_{2}$, and $B_6$ status in tissue by determination of erythrocyte transketolase (TK), glutathione reductase (GR), and aspartate aminotransferase (AST) activities, and their activation by their respective coenzymes, thiamine pyrophosphate, flavin-adenine dinucleotide, and pyridoxal-5-phosphate. The activities of erythrocyte enzymes were stable for more than 30 days when erythrocyte had been stored at $-20^{\circ}C$ and affirmed that the enzyme activities were more stable in the case of deep frozen sotrage of erythrocytes rather than hemolysates. The assay procedures involving ultraviolet kinetic analysis with continuous monitoring for each of enzymes have good within-batch and between-batch precisions and will be avalable in the routine laboratories for the nutritional and clinical surveys. Activity coefficient of TK, GR, and AST was studied in healthy medical students (fifteen men and twelve women, between 21 and 30 years old) on an unrestricted diet. The mean activity coefficient of TK, GR, and AST were 1.18, 1.35, and 2.01 for men, and 1.14, 1.33, and 1.83 for women, respectively. And the upper limit of normal (mean+2SD) were 1.52, 1.69, and 2.61 for men, and 1.50, 1.61, and 2.37 for women, respectively.

• 한국식품위생안전성학회지
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• 제38권1호
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• pp.26-30
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• 2023

본 연구에서는 자외선 살균기의 미생물 오염 상태를 분석하고 위생관리 방안을 제시하고자 하였다. 본 실험에 사용된 자외선 살균기는 전라남도 소재 일부 보육시설 98곳의 자외선 살균기를 대상으로 하였다. 일반세균 및 대장균군은 식품공전 미생물 시험법에 따라 실험하였다. 일반 세균은 98개 보육시설 중 67개소(68.4%), 대장균군은 5개 소(5.1%)에서 검출되었다. 식중독세균 실험 결과 Salmonella spp. 등 6종의 식중독세균은 검출되지 않았지만 B. cereus 는 98개 보육시설 중 1개소(2.8%)에서 검출되었다. 자외선 램프 교체 주기에 따른 일반세균 검출율은 3개월 이내가 6개 보육시설 중 3개소(50%), 3개월 이상 6개월 이내가 5개 보육시설 중 3개소(60%), 6개월 이상이 87개 보육시설 중 61개소(70.1%)로 나타났다. 대장균군 검출율은 6개월 이내에는 검출되지 않았으나 6개월 이상이 87개 보육시설 중 5개소(5.7%)로 나타났다. 자외선 살균기의 미생물 오염도는 램프 교체 주기가 길어질수록 미생물 오염도가 높게 나타났다. 또한 자외선 램프 교체 주기가 6개월 이상인 87개 보육시설 중 23개소(26.4%)의 자외선 살균기 반사판에는 물기가 있고 청소상태가 불량한 것으로 나타났다. 이러한 결과를 종합해 볼 때 보육시설에서 사용 중인 자외선 살균기의 위생관리를 위해 주기적인 청소 와 자외선 램프 교체가 필요한 것으로 판단된다. 또한 보육시설 급식담당자들에게 자외선 살균기 청결과 램프 교체에 대한 지속적인 교육이 필요할 것으로 판단되었다.