• 제목/요약/키워드: Lee Seong-Ah

검색결과 374건 처리시간 0.03초

Low-dose radiation activates Nrf1/2 through reactive species and the Ca2+/ERK1/2 signaling pathway in human skin fibroblast cells

  • Lee, Eun Kyeong;Kim, Jin-Ah;Park, Seong Joon;Kim, Jeung Ki;Heo, Kyu;Yang, Kwang Mo;Son, Tae Gen
    • BMB Reports
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    • 제46권5호
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    • pp.258-263
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    • 2013
  • In the current study, we explored the effect of LDR on the activation of Nrfs transcription factor involved in cellular redox events. Experiments were carried out utilizing 0.05 and 0.5 Gy X-ray irradiated normal human skin fibroblast HS27 cells. The results showed LDR induced Nrf1 and Nrf2 activation and expression of antioxidant genes HO-1, Mn-SOD, and NQO1. In particular, 0.05 Gy-irradiation increased only Nrf1 activation, but 0.5 Gy induced both Nrf1 and Nrf2 activation. LDR-mediated Nrf1/2 activation was accompanied by reactive species (RS) generation and $Ca^{2+}$ flux. This effect was abolished in the presence of N-acetyl-cysteine and BAPTA- AM. Furthermore, Nrf1/2 activation by LDR was suppressed by PD98059, an inhibitor of ERK1/2. In conclusion, LDR induces Nrf1 and Nrf2 activation and expression of Nrf-regulated antioxidant defense genes through RS and $Ca^{2+}$/ERK1/2 pathways, suggesting new insights into the molecular mechanism underlying the beneficial role of LDR in HS27 cells.

양송이 이핵균주의 생화학적 특성 검정 (Biochemical Characterization of Agaricus bisporus Dikaryon Strains)

  • 권혁우;김준영;민성환;최민아;오연이;공원식;김성환
    • 한국균학회지
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    • 제42권1호
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    • pp.86-90
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    • 2014
  • 본 연구에서는 양송이 육종에 필요한 기본 정보를 얻고자 다양한 출처의 양송이 이핵균주를 대상으로 생육 및 생화학적 특성을 비교 검정하였다. 시험한 31균주 중 대부분의 균주가 Oatmeal agar에서 MEA나 PDA에서 보다 균사생장이 우수하였다. 7가지 세포외효소 활성 비교에서 양송이 균주는 대체로 ${\beta}$-glucosidase가 가장 뚜렷한 활성을 나타내었으며 protease의 활성은 모든 균주가 지니고 있었다. ${\beta}$-glucosidase 활성은 27개 균주에서 xylanase 활성은 30개 균주에서 나타났다. 이에 반해 avicelase, CM-cellulase, amylase, pectinase 활성은 20균주 이하에서만 나타났다. 본 연구 결과는 국내 양송이 육종을 위한 균주 선발 기준 중 하나로 이용될 수 있을 것이다.

Nano-Powder 제조를 위한 RF Thermal Plasma Torch System 개발 및 Nano-Si 특성 연구

  • 송석균;손병구;김병훈;이문원;신명선;최선용;김성인
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.179-179
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    • 2012
  • 국내에는 나노 분말 제조를 위한 RF 열플라즈마 시스템 제조 기술이 확보되어 있지 않고, 또한 나노 파우더 제조를 위한 공정 기술 역시 외국 업체에 전적으로 의존하고 있다. 본 연구에서는 나노 분말 제조를 위한 RF 열 플라즈마 토치 시스템 개발과 고품질의 나노 파우더 합성 공정 기술을 확립하여 필요 기관에 제공하는데 있다. 80 kW RF Plasma torch system의 설계 및 제작을 위해 플라즈마 Simulator인 CFD-ACE+를 이용하여 플라즈마 토치 및 반응로 내의 온도 분포, 유체 유동, 열전달 등의 해석을 통해 플라즈마 토치 및 반응로의 반경 및 길이, 구조의 설계 값을 도출하여 반응로를 설계하여 RF 파워, RF 플라즈마 토치(Torch), 반응기(Reactor), 사이클론(Cyclone), 포집부(Collector), 열교환기 및 진공배기 시스템으로 구성하였다. Si 나노 소재의 경우, 이차전지 음극재에 적용이 가능한 대표적인 소재로서 높음 비용량과 충/방전시 부피팽창을 감소시킬 수 있어 이차전지의 고용량 구현을 위해서는 가장 중요한 소재중 하나로 많은 관심 재료로 평가 받고 있다. 따라서 본 연구에서는 상용화된 Si 원료 powder를 사용하여 고상 분체 공급 장치를 통하여 고온의 플라즈마를 통과시켜 기상화 및 결정화과정을 통해 Si 나노분말을 제조하였다. 공정 변수로서 공정압력 및 플라즈마 power, Gas의 변화량에 따른 나노 분말의 제조 특성에 대한 실험을 진행한 후 제조된 나노 분말을 비표면적측정(BET) 및 SEM 측정 결과 분석을 통하여 시스템 특성을 파악하였으며 제조된 Si 나노 파우더는 이차전지 음극재로서 770 mAh/g의 용량과 93%@50 cycle 수준의 유지율을 나타내었다.

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Coordination Modes and Properties of Ag(I) Complex with N,N,N',N',N''-Pentamethyldiethylenetriamine

  • Chun, In-Sung;Kwon, Jung-Ah;Bae, Myung-Nam;Lee, Sim-Seong;Jung, Ok-Sang
    • Bulletin of the Korean Chemical Society
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    • 제27권7호
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    • pp.1005-1008
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    • 2006
  • The reaction of $AgClO_{4}$ with acyclic potential tridentate N,N,N',N',N''-pentamethyldiethylenetriamine (pmdeta) has given colorless crystals suitable for X-ray crystallography. The crystal structure ($P2_{1}$/n, a = 14.413(1) $\AA$, b = 25.270(2) $\AA$, c = 16.130(1) $\AA$, b = $103.012(1){^{\circ}}$, V = 5723.7(8) A$\AA^{3}$, Z = 4, R = 0.0349) has been solved and refined. Three silver(I) ions connect four pmdeta ligands to produce discrete complex of $[Ag_3(pmdeta)_4](ClO_4)_3$. A pmdeta ligand is bridged to three silver(I) ions, and three other pmdeta ligands are chelated to each silver(I) center in a tridentate mode. Thus, the product is a rare tri-nuclear silver(I) complex with two different chemical environments. $^{13}C$ NMR and $MAS\;^{13}$C NMR indicate that the tri-nuclear silver(I) complex is not rigid in solution. The contact angles and thermal analyses of the complex are measured and discussed.

Eating habits and eating behaviors by family dinner frequency in the lower-grade elementary school students

  • Lee, Seo Yeon;Ha, Seong Ah;Seo, Jung Sook;Sohn, Cheong Min;Park, Hae Ryun;Kim, Kyung Won
    • Nutrition Research and Practice
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    • 제8권6호
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    • pp.679-687
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    • 2014
  • BACKGROUND/OBJECTIVES: Recently, there has been an increased interest in the importance of family meals on children's health and nutrition. This study aims to examine if the eating habits and eating behaviors of children are different according to the frequency of family dinners. SUBJECTS/METHODS: The subjects were third-grade students from 70 elementary schools in 17 cities nationwide. A two-stage stratified cluster sampling was employed. The survey questionnaire was composed of items that examined the general characteristics, family meals, eating habits, eating behaviors, and environmental influence on children's eating. The subjects responded to a self-reported questionnaire. Excluding the incomplete responses, the data (n = 3,435) were analyzed using ${\chi}^2$-test or t-test. RESULTS: The group that had more frequent family dinners (${\geq}$ 5 days/week, 63.4%), compared to those that had less (${\leq}$ 4 days/week, 36.6%), showed better eating habits, such as eating meals regularly, performing desirable behaviors during meals, having breakfast frequently, having breakfast with family members (P < 0.001), and not eating only what he or she likes (P < 0.05). Those who had more frequent family dinners also consumed healthy foods with more frequency, including protein foods, dairy products, grains, vegetables, seaweeds (P < 0.001), and fruits (P < 0.01). However, unhealthy eating behaviors (e.g., eating fatty foods, salty foods, sweets, etc.) were not significantly different by the frequency of family dinners. CONCLUSIONS: Having dinner frequently with family members was associated with more desirable eating habits and with healthy eating behaviors in young children. Thus nutrition education might be planned to promote family dinners, by emphasizing the benefits of having family meals on children's health and nutrition and making more opportunities for family meals.

리튬 이차전지에서 Si 음극박막의 스퍼터링 증착조건에 따르는 구조적, 전기화학적 특성 연구 (Influence of Sputtering Conditions on Structural and Electrochemical Properties of the Si Anode Film for Lithium Secondary Batteries)

  • 주승현;이성래;조병원;조원일
    • 한국재료학회지
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    • 제19권2호
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    • pp.73-78
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    • 2009
  • This study investigated the dependence of the various sputtering conditions (Ar pressure: $2{\sim}10\;mTorr$, Power: $50{\sim}150\;W$) and thickness ($50{\sim}1200\;nm$) of Si thin film on the electrochemical properties, microstructural properties and the capacity fading of a Si thin film anode. A Si layer and a Ti buffer layer were deposited on Copper foil by RF-magnetron sputtering. At 10 mTorr, the 50 W sample showed the best capacity of 3323 mAh/g, while the 100 W sample showed the best capacity retention of 91.7%, also at 10 mTorr. The initial capacities and capacity retention in the samples apart from the 50W sample at 10 mTorr were enhanced as the Ar pressure and power increased. This was considered to be related to the change of the microstructure and the surface morphology by various sputtering conditions. In addition, thinner Si film anodes showed better cycling performance. This phenomenon is caused by the structural stress and peeling off of the Si layer by the high volume change of Si during the charge/discharge process.

양송이 재배사 공기 중에 존재하는 세균조사 (Investigation of bacteria in indoor air of a greenhouse for button mushroom cultivation)

  • 권혁우;최민아;오연이;공원식;김성환
    • 한국버섯학회지
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    • 제13권1호
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    • pp.26-29
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    • 2015
  • 양송이는 재배사라는 밀폐된 환경에서 재배되는 바 양질의 생산을 위해서는 재배사 내 환경에 대한 정보가 요구된다. 본 연구는 양송이 재배사내 실내환경에 대한 기초 정보를 얻고자 수행되었다. 재배사 내 온도와 습도는 $19.75{\pm}0.35^{\circ}C$, $87{\pm}3.67%$로 세균이 서식할 수 있는 환경조건이었으며, 부유세균의 농도는 $3.84{\times}10^3cfu/m^3$로서 환경부에서 고시한 실내공기질 오염유지 기준치인 $8.0{\times}10^2cfu/m^3$을 초과하는 수치였다. 분리된 부유세균은 Advenella kashmirensis, Bacillus vietnamensism, B. licheniformis, Burkholderia sordidicola, Fictibacillus phosphorivorans, Lysobacter daejeonensis, Microbacterium esteraromaticum, Pseudomonas aeruginosa, P. protegens, P. gessardii, P. mosseli 등 7속 11종으로 동정되었다.

속도계측형 호흡기류센서에서 상승시간을 고려한 최고호기유량의 교정 기법 (Compensation of Peak Expiratory Air Flow Rate Considering Initial Slope in Velocity Type Air Flow Transducer)

  • 차은종;이인광;김성식;김완석;박경순;김원재;김경아
    • 전기학회논문지
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    • 제58권4호
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    • pp.867-872
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    • 2009
  • Peak expiratory flow rate(PEF) is one of the most important diagnostic parameters in spirometry. PEF occurs in a very short duration during the forced expiratory maneuver, which could lead to measurement error due to non-ideal dynamic characteristic of the transducer. In such case the initial slope of the flow rate signal determines the accuracy of the measured PEF. The present study considered this initial slope as a parameter to compensate PEF. The 26 standard flow rate signals recommended by the American Thoracic Society(ATS) were flown through the air flow transducer followed by simultaneous measurements of PEF and maximum transducer output$(N_{PEF})$. $N_{PEF}$-PEF satisfied a quadratic equation in general, however, two signals (ATS #2 and #26) having large initial slopes deviated from the fitting equation to a significant degree. The relative error was found to be in a linear relationship with the initial slope, thus, $N_{PEF}$ was appropriately compensated to provide accurate PEF with mean relative error less than only 1%. The 99% confidence interval of the mean relative error was less than a half of the error limit of 5% recommended by ATS. Therefore, PEF can be very accurately determined by compensating the transducer output based on the initial slope, which should be a useful technique for air flow transducer calibration.

Anti-inflammatory Activity of Stevia rebaudiana in LPS-induced RAW 264.7 Cells

  • Jeong, Il-Yun;Lee, Hyo-Jung;Jin, Chang-Hyun;Park, Yong-Dae;Choi, Dae-Seong;Kang, Min-Ah
    • Preventive Nutrition and Food Science
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    • 제15권1호
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    • pp.14-18
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    • 2010
  • Stevia rebaudiana (SR) is an herb used traditionally as a sweetener in Paraguay and Brazil, whose use is spreading to other countries, such as Japan, Korea and China. In addition to its low calorie sweet taste, SR appears to have other beneficial properties, such as hypotensive capabilities and inflammation reduction. To identify the bioactive natural constituents exerting anti-inflammatory activities, we examined the EtOAc fraction of SR. In the inflammatory mediator inhibitory assay from lipopolysaccharide (LPS)-activated macrophages, the EtOAc fraction significantly, and dose dependently, inhibited the enhanced production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS) expression. We also found that treatment of cells with the EtOAc fraction significantly inhibited LPS-stimulated nuclear factor-${\kappa}B$ (NF-${\kappa}B$) reporter gene expression. Such inhibition of NF-${\kappa}B$ was closely associated with the inhibition of interleukin-6 (IL-6) and the monocyte chemoattractant protein-1 (MCP-1). Therefore, we suggest that SR has the potential for development as a functional food for the treatment of immune diseases, such as rheumatoid arthritis and lupus.

외반슬 환자의 교정운동의 효과: 단일 피험자 A-B-A 실험 설계 (The Effect of Corrective Exercise in a patient with knee joint valgus deformity: A single-subject A-B-A experimental design)

  • 이호성;김아람
    • 대한물리의학회지
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    • 제11권1호
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    • pp.93-105
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    • 2016
  • PURPOSE: The purpose of this study was to determine the effect of corrective exercise on hip joint range of motion, lower limb alignment, radiographs of hip and knee joints, and quadriceps muscle activity in a patient with knee joint valgus deformity. METHODS: A single-subject A-B-A experimental design was used to determine the effects of therapeutic exercise. The single-subject was a 27-year-old male, who presented with knee joint valgus deformity. Corrective exercise program was performed for 40 min/day twice a week for 12-week. Range of motion (hip flexion, extension, abduction, adduction, internal rotation, and external rotation), lower limb alignment test (Q-angle, rear foot alignment, and leg length), standing anterior-posterior radiographs (neck shaft angle and knee joint space), and quadriceps muscle activity of both lower limbs were measured before (A 1), after 6 weeks (B 1) and after 12-weeks (B 2) of corrective exercise and after 6 weeks of exercise completion (A 2). RESULTS: Hip range of motion increased in all directions of both sides at B 2 and A 2 compared to at A 1. Q-angle of both side and leg length discrepancy decreased at B 2 and A 2 compared to at A 1. Neck shaft angle and knee joint space of both sides improve at B 2 and A 2 compared to at A 1. Quadriceps of both side muscle activities improved at B 2 and A 2 compared to at A 1. CONCLUSION: We demonstrated that corrective exercise increases range of motion, and improves lower limb alignment and muscle activity in a patient with knee joint valgus deformity.