Comparison of trophic factors changes in the hippocampal CA1 region between the young and adult gerbil induced by transient cerebral ischemia.

Yan, Bing Chun,Park, Joon Ha,Kim, Sung Koo,Choi, Jung Hoon,Lee, Choong Hyun,Yoo, Ki-Yeon,Kwon, Young-Geun,Kim, Young-Myeong,Kim, Jong-Dai,Won, Moo-Ho Kluwer Academic/Plenum Publishers 2012 Cellular and molecular neurobiology Vol.32 No.8

<P>In the present study, we investigated neuronal death/damage in the gerbil hippocampal CA1 region (CA1) and compared changes in some trophic factors, such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF), in the CA1 between the adult and young gerbils after 5 min of transient cerebral ischemia. Most of pyramidal neurons (89%) were damaged 4 days after ischemia-reperfusion (I-R) in the adult; however, in the young, about 59% of pyramidal neurons were damaged 7 days after I-R. The immunoreactivity and levels of BDNF and VEGF, not GDNF, in the CA1 of the normal young were lower than those in the normal adult. Four days after I-R in the adult group, the immunoreactivity and levels of BDNF and VEGF were distinctively decreased, and the immunoreactivity and level of GDNF were increased. However, in the young group, all of their immunoreactivities and levels were much higher than those in the normal young group. From 7 days after I-R, all the immunoreactivities and levels were apparently decreased compared to those of the normal adult and young. In brief, we confirmed our recent finding: more delayed and less neuronal death occurred in the young following I-R, and we newly found that the immunoreactivities of trophic factors, such as BDNF, GDNF, and VEGF, in the stratum pyramidale of the CA1 in the young gerbil were much higher than those in the adult gerbil 4 days after transient cerebral ischemia.</P>

연 X-선 현미경을 이용한 금 나노입자 세포영상

권영만,김한경,김경우,김선희,윤홍화,천권수,강성훈,박성훈,정선관,윤권하 韓國電子顯微鏡學會 2008 Applied microscopy Vol.38 No.3

연 x-선 현미경은 ‘물의 창’ 영역(2.3~4.4 nm)의 파장을 이용하여, 수십 nm의 분해능으로 세포를 파괴하지 않고 살아있는 상태에서 세포의 내부구조를 관찰할 수 있어 가시광선현미경과 전자현미경을 단점을 보완하는 특징을 갖는 세포 생물학 연구에 적합한 현미경이다. 그러나 기존 연 x-선 현미경은 광원으로 방사선 가속기를 이용하기 때문에 사용이 제한적이었다. 이에, 본 연구에서는 2.88 nm의 연 x-선을 광원으로 사용하는 소형 연 x-선 현미경을 이용하여, 내포작용에 의해 금 나노입자를 포획한 HT1080과 MDA-MB 231 세포의 영상을 약 60 nm 분해능으로 획득하였다. 금 나노입자의 세포에 대한 독성을 제거하기 위하여 폴리에틸렌 글리콜을 캡핑하였고, 2.88 nm 파장의 연 x-선에 대하여 충분한 조영효과로 인하여 세포영상에서 뚜렷한 대조도를 나타내었다. 내포작용에 의해 액포에 포함되어 있는 다양한 크기의 금 나노입자 군집을 확인하였으며, 세포내부의 액포의 분포상태도 관찰할 수 있었다. 따라서 고분해능을 가진 소형 연 x-선 현미경을 이용하여 금 나노입자를 세포내의 미세기관이나 특정 단백질에 표지하면 연 x-선에 대한 조영효과의 증가에 의하여 더욱 유용한 정보를 획득할 수 있을 것으로 생각한다. A compact soft x-ray microscope operated in the ‘water window’ wavelength region (2.3~4.4 nm) was used for observing cells with nano-scale spatial resolution. To obtain cellular imaging captured with colloidal gold nanoparticles using a compact soft x-ray microscope. The colloidal gold nanoparticles showed higher contrast and lower transmission more than 7 times than that of cellular protein on the soft x-ray wavelength region. The structure and thickness of the cell membrane of the Coscinodiscus oculoides (diatome) and red blood cells were seen clearly. The gold nanoparticles within the HT1080 and MDA-MB 231 cells were seen clearly on the soft x-ray microscopy. The gold nanoparticles were aggregated within vesicles by endocytosis.

Assessment of Alcohol Level in Inebriated Victims of Sexual Assault using Ethyl Glucuronide

Young?Hoon Jo,Mia Kwon,Joon-Bae Lee,Jeong A Ko 한국분석과학회 2022 학술대회논문집 Vol.2022 No.5

Mechanical Characterization of Nano-Structured Materials Using Nanoindentation

( Ju Young Kim ),( Sung Hoon Kim ),( Jung Suk Lee ),( Kyung Woo Lee ),( Dong Il Kwon ) 대한금속재료학회 ( 구 대한금속학회 ) 2006 METALS AND MATERIALS International Vol.12 No.3

The principal strengths of the nanoindentation technique, which is used extensively to measure the mechanical properties of nano/micro materials, are easy sample preparation and simple experimental method. Hardness and Young`s modulus are essential properties measured by nanoindentation; hardness corresponds to resistance to plastic deformation whereas Young`s modulus is related to elastic deformation. Two key difficulties arise in association with nanoindentation on small volumes: measurement accuracy and material response. Here we discuss the indentation size effect (ISE) considering tip bluntness and variation in hardness of nano-multilayers with a bilayer period, representative research on measurement improvement, and material response at nanoscales.

소규모 하수처리를 위한 파일럿 규모 이중슬러지 KNR^® (Kwon's nutrient removal) 시스템의 영얌염류 제거성능 평가

안진영,권중천,김윤학,정유훈,김두언,유선호,김병우,An, Jin-Young,Kwon, Joong-Chun,Kim, Yun-Hak,Jeng, Yoo-Hoon,Kim, Doo-Eon,Ryu, Sun-Ho,Kim, Byung-Woo 한국청정기술학회 2006 청정기술 Vol.12 No.2

본 연구에서 소규모 하수고도처리를 위한 이중슬러지(Dual sludge) $KNR^{(R)}$ (Kwon's nutrient removal) 시스템이 개발되었다. $KNR^{(R)}$ 시스템은 부유성장식 탈질미생물과 부착성장식 질산화미생물을 분리시킨 이중슬러지 공정으로 최초침전조, 혐기조, 무산소조, 농축조의 복합기능을 수행하는 UMBR (Upflow multi-layer bioreactor)과 펠렛형 담체가 충진된 호기성 담체조로 구성되어 있다. 소규모 하수처리시 본 개발공정의 안정성과 처리성능을 평가하기 위해 처리용량 $50m^3/d$ 규모의 파일럿 플랜트를 고도처리 공정으로 개선공사 중인 처리용량 $50m^3/d$ 규모의 실제 소규모 마을하수처리장에 적용하였다. UMBR과 담체조의 체류시간은 각각 4.7 h와 7.2h이었으며, 반응조 수온은 $18.1{\sim}28.1^{\circ}C$이었다. 유입 하수량과 유입수의 BOD/N의 변동폭이 컸음에도 불구하고 파일럿 플랜트는 안정된 처리성능을 보였다. 전체 실험기간 중 처리수의 $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, TP의 평균 농도는 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, 0.87/0.17 mg/L (poly aluminium chloride(PAC) 투입/미투입)이었으며, 제거율을 각각 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, 55.4/90.3% 이었다. 잉여슬러지 발생량은 $A_2O$와 Bardenpho 등과 같은 단일슬러지를 이용하는 고도처리공정과 비교시 약 1.9~3.8배 낮은 $0.026kg-DS/m^3$ and 0.220 kg-DS/kg-BOD로 나타났다. A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

mRNA의 3' end processing에 대한 mRNA 중합요소 인산화의 영향

권대환,박재현,송영하,안성훈 한양대학교 이학기술연구소 2006 이학기술논문지 Vol.9 No.-

RNA 중합효소의 C-terminal은 YSPTSPS의 반복적인 아미노산 서열을 갖고 있으며, 이들의 인산화는 전사의 개시, 중합, 또는 종결단계에 중요하다고 알려져 있다. 본 연구에서는 이러한 RNA 중합효소의 인산화가 mRNA의 3' end processing에 미치는 영향을 조사하였다. C-terminal domain (CTD) of RNA polymerase Ⅱ contains a repeated heptameric sequence (YSPTSPS) which is phosphorylated at serine 2 and 5. Phosphorylation of CTD in elongating RNA polymerase Ⅱ has been suggested to play a role in transcriptional initiation, elongation or termination. In the present study, we investigated the effect of RNA polymerase Ⅱ CTD phosphorylation on the 3' end processing of mRNA.

허혈성 심질환에서 나타나는 황상화지수, 사이토카인 및 염증지표의 변화

전상훈,안지훈,방덕원,온영근,현민수,김성구,권영주 순천향대학교 의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

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신경회로망 제어기를 이용한 PID 파라미터 추정에 관한 연구

權重東,裵銀敬,金恩基,全基英,李承桓,吳鳳煥,李勳九,金容珠,韓慶熙 明知大學校 産業技術硏究所 2006 産業技術硏究所論文集 Vol.25 No.-

In this paper, supposed to solve these problem to PID parameters controller algorithm using ANN. In the proposed algorithm, the parameters of the controller were adjusted to reduce by on-line system the error of the speed of IM. In this process, EBPA NN was constituted to an output error value of an IM and conspired an input and output. The performance of the self-tuning controller is compared with that of the PH) controller tuned by conventional method (Ziehler-Nichols). The effectiveness of the proposed control method is verified thought the Matlab Simulink and experimental results.

다공질 Si의 열적 안정성 연구

권영해,조훈영,홍치유 동국대학교 자연과학연구원 1995 자연과학연구 논문집 Vol.15 No.-

The oxidation and pressure effects of electrochemically etched porous Si have been investigated by photoluminescence(PL) and Raman spectroscopy. The porous Si sample was etched with a current density of 50mA/㎠ for 20 min, and shows a PL signal at 710 nm and a Raman peak at 517 cm. Rapid-thermal-annealing of the as-etched sample at 400℃ shows a rapid drop in the PL intensity. On the other hand, the intensity of the rapid-thermal-oxidized sample remains constant in the temperature range from 600℃ to 800℃. The Raman signal of the oxidized sample also showed thermal stability. The reverse leakage current of the oxidized porous Si was reduced to 100 times in comparision to that of as-grown porous Si. The PL peak position of the oxidized porous Si shows the shifts to 705 nm and the Raman peak shifts to a higher energy, closer that of the bulk polycrystalline Si. This can be explained in terms of the stress on the Si columnar structure. The initial tensile stress induced by the etching process is reduced by the compressive stres caused by the formation of oxides (SiO₂) in the gaps. It is supposed that this can cause the blue shift in the PL spectrum and the recovery of the Raman peak position.

유치 수복물에 따른 주변 법랑질의 탈회 저항성 : QLF를 이용한 연구

권해숙,현홍근,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

본 연구에서는 유치 수복물의 불소 방출 여부에 따른 주변 법랑질의 탈회 저항성과 재광화 효과를 살펴보고자 하였다. 건전 유전치 48개를 16개씩 임의로 세 군으로 나누어, FiltekTM Z250(1군), F2000(2군), KetacTM N100(3군)을 사용하여 제조사의 지시에 따라 충전하였다. 3일 동안 인공 우식 병소를 유발한 후, 14일 동안 인공 타액에 담가 재광화를 유발하였다. Quantitative light-induced fluorescence(QLF)를 이용하여 실험 단계와 시간에 따른 무기질 소실량(ΔQ)의 변화를 관찰한 결과는 다음과 같다. 1. 탈회가 일어난 인공 우식 병소의 ΔQ 값은 3군, 2군, 1군 순으로 작게 나타났고, 이 중 3군은 1군에 비해 유의한 탈회 저항성을 보였다. 2. 1군, 2군, 3군 모두 재광화 1일 후부터 초기 인공 우식 병소의 ΔQ 값과 비교 시 유의한 차를 보였으며, 관찰 기간 동안 지속적인 증가 양상을 나타내었다. 3. 재광화 속도를 의미하는 Δ(ΔQ)/일 값은 각 군에서 처음 1일 동안 유의성 있게 크게 나타났으며, 그 이후 급속히 감소하였다. 4. 수복 재료에 따른 재광화 정도는 각 군 간에 유의한 차이가 없었다. The objective of this in vitro study was to detect and monitor demineralization and remineralization of primary teeth according to restorative materials using quantitative light-induced fluorescence (QLF). A single bur hole was drilled on the each sound forty eight primary anterior teeth, and the specimens were divided into three groups. The cavity was restored with FiltekTM Z250(Group 1), F2000(Group 2), KetacTM N100(Group 3) following the manufacturer's instructions. The teeth were subjected to the demineralizing buffer for 3 days, and then subjected to a remineralizing buffer for 14 days. The change of mineral loss(ΔQ) according to the stages was evaluated by QLF and the following results were obtained: 1. When demineralization was done, ΔQ was increased as follows. : Group 1 (-110.79 ± 27.77) < Group 2 (-104.84 ± 28.95) < Group 3 (-90.16 ± 21.87) : Resistance to demineralization was statistically significant in Group 3. 2. There was a statistically significant increase in ΔQ of all groups since 1st day of remineralization 3. The rate of remineralization, Δ(ΔQ)/day, showed significant high value in each group on the 1st day then decreased rapidly. 4. There was no statistically significant difference in the degree of remineralization among restorative materials.