• Molecules and Cells
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• 제22권2호
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• pp.203-209
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• 2006

TBP (TATA-binding protein)-related factor 2 (TRF2) regulates transcription during a nuber of cellular processes. We previously demonstrated that it is localized in the cytoplasm and is translocated to the nucleus by DNA-damaging agents. However, the cytoplasmic localization of TRF2 is controversial. In this study, we reconfirmed its cytoplasmic localization in various ways and examined its nuclear migration. Stresses such as heat shock, redox agents, heavy metals, and osmotic shock did not affect localization whereas genotoxins such as methyl methanesulfonate (MMS), cisplatin, etoposide, and hydroxyurea caused it to migrate to the nucleus. Adriamycin, mitomycin C and ${\gamma}$-rays had no obvious effect. We determined optimal conditions for the nuclear migration. The proportions of cells with nuclei enriched for TRF2 were 25-60% and 5-10% for stressed cells and control cells, respectively. Nuclear translocation was observed after 1 h, 4 h and 12 h for cisplatin, etoposide and MMS and hydroxyurea, respectively. The association of TRF2 with the chromatin and promoter region of the proliferating cell nuclear antigen (PCNA) gene, a putative target of TRF2, was increased by MMS treatment. Thus TRF2 may be involved in genotoxin-induced transcriptional regulation.

• 한국노년학
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• 제29권2호
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• pp.657-667
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• 2009

본 연구는 규칙적인 유산소 운동이 성장에 따른 세포 복제현상에 미치는 영향을 살펴보기 위하여 염색체 말단에 위치한 텔로미어의 길이와 결합단백질인 TRF 2(telomere repeat binding factor 2)의 발현량을 분석하였다. 흰쥐를 대상으로 장기간 운동집단, 단기간 운동집단, 비교집단 그리고 기준수준 검증을 위한 기준집단의 4집단으로 각각 7마리씩 총28마리를 배정하였으며, 수영 운동은 무부하 자유유영의 형태로 주 5회, 매회 1시간씩 실시하였다. 마지막 운동 종료 후 24시간 뒤 쥐를 희생시켜 심장, 간, 가자미근을 적출하여 genomic DNA를 추출, 텔로미어의 길이와 관련단백질인 TRF 2의 발현량을 분석하였다. 연구 결과, 간조직의 텔로미어 길이와 TRF 2 단백질의 발현량은 집단 간 차이를 발견할 수 없었으나, 심장조직의 텔로미어 길이는 장기간 운동집단이 비교집단 및 단기간 운동집단에 비해 길게 나타났고, TRF 2의 단백질 발현 또한 높게 나타나, 장기간의 수영 운동이 성장에 따른 심장의 텔로미어 단축현상을 지연시키는 효과가 있는 것으로 나타났다. 또한, 가자미근에서는 4주령의 기준집단에 비해 비교집단과 단기간 운동집단의 텔로미어의 길이는 유의하게 짧았으나, 장기간 운동집단과는 유의한 차이가 나타나지 않은 것으로 미루어 장기간의 수영 운동이 골격근의 복제적 노화현상도 억제할 수 있는 가능성을 관찰할 수 있었다.

• Structural Engineering and Mechanics
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• 제60권2호
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• pp.251-269
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• 2016

In common structural systems, there are some limitations to provide adequate lateral stiffness, high ductility, and architectural openings simultaneously. Consequently, the concept of T-Resisting Frame (TRF) has been introduced to improve the performance of structures. In this study, Configuration of TRF is a Vertical I-shaped Plate Girder (V.P.G) which is placed in the middle of the span and connected to side columns by two Horizontal Plate Girders (H.P.Gs) at each story level. System performance is improved by utilizing rigid connections in link beams (H.P.Gs). Plastic deformation leads to tension field action in H.P.Gs and causes energy dissipation in TRF; therefore, V.P.G. High plastic deformation in web of TRF's members affects the ductility of system. Moreover, in order to prevent shear buckling in web of TRF's members and improve overall performance of the system, appropriate criteria for placement of web stiffeners are presented in this study. In addition, an experimental study is conducted by applying cyclic loading and using finite element models. As a result, hysteresis curves indicate adequate lateral stiffness, stable hysteretic behavior, and high ductility factor of 6.73.

• Food Science and Biotechnology
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• 제18권6호
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• pp.1528-1531
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• 2009

In this study, we investigated a dose-dependent hypolipidemic and antioxidant effects of tocotrienol-rich fraction (TRF) from grape seeds. After induction of hyperlipidemia for 4 weeks, rats were supplemented with different dose (5, 25, and 50 mg/kg BW/day) of TRF for 1 week. Oral administration of TRF (50 mg/kg BW/day) decreased the plasma triglyceride (TG, 162.6 mg/dL), total cholesterol (TC, 83.7 mg/dL), low density lipoprotein-cholesterol (LDL-C, 20.3 mg/dL), malondialdehyde contents (MDA, 3.3 nmol/dL), and atherogenic index (AI, 2.0) compare to high-fat diet group. These data suggest that TRF supplementation has significant health benefits through the modulation of physiological functions that include various atherogenic lipid profiles and antioxidative status in hyperlipidemia.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2003년도 춘계학술발표대회 요약집
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• pp.294.2-294.2
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• 2003

• Journal of the Korean Wood Science and Technology
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• 제51권2호
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• pp.81-97
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• 2023

The aim of this study were to evaluate tannin resorcinol formaldehyde (TRF) for the preparation of cross-laminated timbers (CLTs) made from fast-growing tree species and to analyze the physical and mechanical properties of CLTs. TRF copolymer resin was prepared by using the bark extracts of Swietenia mahagoni (L.) Jacq. It was observed that the TRF adhesive possessed less solid content (23.59%), high viscosity (11.35 poise), and high pH values (10.0) compared to the standard phenol resorcinol formaldehyde. The TRF adhesive was applied to produce CLTs with the addition of 15% tapioca and flour as an extender. The six-layered CLTs were produced from sengon (Falcataria moluccana Miq.), jabon [Anthocephalus cadamba (Roxb) Miq.], coconut (Cocos nucifera L.), and the combination of coconut-jabon and coconut-sengon wood. The analysis of variance revealed that the layer composition of CLT significantly affected the physical and mechanical properties of the beam. While the modulus of rupture met the standard, the moisture content and modulus of elasticity values did not fulfill JAS 1152-2007. All of the CLTs produced in this study demonstrated low formaldehyde emission, ranging from 0.001 mg/L to 0.003 mg/L, thereby satisfying the JAS 1152 for structural glue laminated timber.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.43-44
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• 2010

We present the analysis of space geodetic technique observation, Satellite Laser Ranging (SLR), to LAGEOS1 and LAGEOS2 for the definition of the Terrestrial Reference Frame (TRF). The data were analyzed in 7day arcs during about 9 years (2000/01/10 ~ 2008/12/29) using NASA Goddard's GEODYN/SOLVE II software. The comparison of the coordinates between ITRF2005 and TRF solutions determined in this work shows that there is no significant bias.

• 약학회지
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• 제41권3호
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• pp.305-311
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• 1997

Sustained release-microspheres and immediate release-pellets were prepared to develop a controlled release multiparticulate system containing both water soluble and insoluble dr ug. Pseudoephedrin.HCl (EPD) and terfenadine (TRF) were used as model drugs, respectively. Sustained release-EPD microspheres were prepared by solvent evaporation method using Eudragit RL or RS as a matrix combined with pH-insensitive film coating. Smaller EPD microspheres were obtained when smaller amount of Eudragit as a matrix material or larger amount of magnesium stearate as a dispersing agent was used. However the obtained microspheres did not show syfficient sustained release characteristics. About 97% of EPD was released after 1 hr irrespective of matrix material used. Subsequent coating of the microspheres with pH-insensitive polymer such as Eudragit RS or ethylcelulose (EC) resulted good sustained in 37.5, 73.3 and 92.0% release of encapsulated EPD in distilled water after 1, 3 abd 7 hr, respectively. It corresponds to mean dissolution time (MDT) of 2.3 hr, which is much larger than that of un-coated EPD microspheres (0.0048 hr). Immediate release TRF pellets were prepared by spherically agglomerated crystallization using Eudragit E as an inert matrix and methylene chloride as a liquid binder. Using Eudragit E alone as a matrix resulted in satisfactory physical properties of the pellets such as sphericity, surface texture and flowability, but led to slower release of TRF from pellets than un-modified TRF powder (MDT of 1.70 vs 1.43 hr in pH 1.2 dissolution medium). Introducing propylene glycol or sodium lauryl sulfate as an emulsifier brought about faster release of TRF from pellets (MDT of 1.14 and 0.95 hr, respectively). In conclusion, microencapsulation by solvent evaporation combined with film coating and spherically agglomerated crystallization were successfully utilized to prepare controlled release multiparticulate system composed of sustained release EPD-microspheres and immediate release TRF pellets.

• 천문학회보
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• 제34권1호
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• pp.107.2-107.2
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• 2009

• 한국대기환경학회지
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• 제28권5호
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• pp.485-494
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• 2012

The purpose of this study is to monitor the flux of $CO_2$ and BVOCs (biogenic volatile organic compounds) between the atmosphere and forest. The main research activities are conducted at Taehwa Research Forest (TRF), managed by the College of Agriculture and Life Sciences at Seoul National University. The TRF site is located 60 km north-east from the center of Seoul Metropolitan Area. The TRF flux tower is in the middle of a Korean Pine (Pinus Koraiensis) plantation ($400m{\times}400m$), surrounded by a mixed forest. Eddy covariance method was used for $CO_2$ flux above the forest and REA (Relaxed eddy accumulation) method applying eddy covariance was used for BVOCs flux. BVOCs flux that was measured in spring (from May 16 to 18) had distribution of 84 to $2917{\mu}g/m^2{\cdot}h$. Especially, it showed that d-limonene being strong reactivity composed the largest fraction of monoterpene. Ambient $CO_2$ concentration measured in Mt. Taehwa was 399 ppm and observed $CO_2$ fluxes between the atmosphere and forest suggested that during the day, $CO_2$ is absorbed by plants through photosynthesis and released during the night.