• Bulletin of the Korean Chemical Society
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• v.20 no.1
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• pp.85-88
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• 1999

Me3NO selectively abstracts the proton from [IrH(CO)(PPh3)2L(A)]0.1+,2+ (1) (A: -CCPh, Cl-, CH3CN and L: CH3CN, Cl-, C1O4-) to give the trans-elimination products, Ir(CO)(PPh3)2(A) (2). The reductive elimination of H+ and Cl- from Ir(H)Cl2(CO)(PPh3)2 (lb) to give IrCl(CO)(PPh3)2 (2b) is first order in both lb and Me3NO. The rate law d[2b]/dt=kobs[lb]=k2[lb][Me3NO] suggests the formation of (PPh3)2(CI)2(CO)Ir-H-ON+Me3 in the rate determining step (k2) followed by the fast dissociation of both H-ON+Me3 and the trans ligand Cl-. The rate significantly varies with the cis liaand A and the trans ligand L and is slower with both A and L being Cl- than other ligands. Me3NO selectively eliminates CO from [Ir(H)2(CO)(PPh3)2L]0,+ (3) (L=CH3CN, C1O4-) to produce [Ir(H)2(PPh3)2L'(CH3CN)]+ (4) (L'=CH3CN, PPh3) in the presence of L. Me3NO does not readily remove either H+ or CO from cis, trans- and trans, trans-lr(H)(-CCPh)2(CO)(PPh3)2 and cis, trans-Ir(H)2Cl(CO)(PPh3)2. The choice whether hydridocarbonyls, 1 and 3 undergo the deprotonation or decarbonylation may be understood mostly in terms of thermodynamic stability of the products and partly by kinetic preference of Me3NO on proton and CO.

• Journal of Life Science
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• v.20 no.4
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• pp.555-560
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• 2010

The objective of this study was to investigate levels of serum creatinine, CuSOD and MnSOD protein expression in the kidney after renal ischemic reperfusion with pre-exercise using heat shock protein 70.1 in knock-out mice (KO). The C57/BL6 strain (Wild type: WT) and KO were divided into 4 groups as follows: Sham control group (Sham), pre-exercise group (Ex), pre-exercise +ischemia group (Ex+IR), and ischemia group (IR). CuSOD and MnSOD expression were significantly decreased (p<0.01, p<0.05) and blood creatinine concentration was significantly increased (p<0.01) in the IR group of KO. In contrast, CuSOD and MnSOD expression in the Ex+IR group of KO were higher than the IR group, while creatinine concentration was significantly lower. These results suggest that Hsp70 is directly correlated to renal ischemic reperfusion injury. Pre-exercise in renal ischemia might prevent or inhibit positive oxidative stress inhibitory effects by increasing anti-oxidative enzymes (CuSOD, MnSOD) within the kidney and improve to prevent renal function. Thus, pre-exercise may have a protective role against renal injury after renal ischemia.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1547_1548
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• 2009

제안된 Fabry-Perot Interferometer (FPI) 어레이 기반 IR 스펙트로미터는 상층부에 FPI 어레이와 하단에 $V_2O_5$ 볼로미터 IR 적외선 센서어레이로 크게 두 부분으로 구성된다. 이 구조에서 다양한 FPI 공진 캐비티의 두께에 의해 특정 공진 파장이 선택되어 진다. 그리고 각각의 볼로미터 IR 디텍터는 IR 파장에 상응하는 투과도를 감지해낸다. 다양한 박막 필터 시뮬레이션 결과를 통해 제작된 FPI 어레이 기반 IR 스펙트로미터는 $3{\sim}5{\mu}m$의 적외선 파장대역에서 흡수 스펙트럼을 가지는 $CH_4$, $CO_2$, $N_2O$, CO 가스 검출을 위해 다층 박막 FPI 층의 다층 박막 FPI 층의 투과율을 높였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.11A
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• pp.1682-1690
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• 2000

최근들어 초광대역 시간 도약 임펄스 무선 전송(ultra wideband time hopping impulse radio; 이하 IR) 기술이 실내 무선 LAN이나 군용 무선 통신 시스템 등을위한 새로운대역 확산 전송 방식으로서 큰 관심을 모으고 있다 IR 시스템은 1(nsec) 이하의 매우 짧은 펄스폭의 펄스 위치 변조(pulse position modulation)된 가우시안 모노사이클 펄스열을 이용함으로서 매우작은 크기 의수 GHz에 이르는 초광대역 스펙트럼을 가지며 기존의 통신 시스템에 거의 간섭을 미치지 않으면서 사용 가능하다. 본 논문에서는 IR 시스템에 M진 (M-ary) PPM 방식을 적용하는 경우의 성능을 평가하였다. 특시 의사 잡음 부호 발생기와 10진 변환기(decimator)로 구성된 시간 도약 패턴을 사용하여 다원 접속 간섭이 배제되는 부가성 백색 가우시안 잡음 채널 하의 동기식(synchronous) IR 시스템에서, 심벌 수, M, 가우시안 모노사이클 펄스 폭 $\tau$$_{p}$, PPM에서 펄스 간 간격$\delta$, 펄스 반복 횟수 N$_{s}$ 등과 같은 다양한 시스템 파라미터의 조합에 따른 성능 변화를 모의 실험을 통해 확인하였으며, 이러한 결과를 통해 비트 오율, 시스템 복잡도 및 전송율 등의 사양에 따라 적합한 M 진 PPM IR 시스템의 구성 방안에 대한 근거를 제공하였다.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.36-43
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• 2007

Elemental analysis, SEM-EDX, X-ray diffraction (XRD) and IR analysis were adopted to examine the quality of charred woods excavated from the underground of the Daewoongjeon Hall of Youngguksa Temple, Youngdong-gun, Chungbuk, Korea. A large amount of calcium was detected in SEM-EDX analysis. The analyses of chemical elements suggested that completely charred wood was carbonized at about $500^{\circ}C$. The XRD results indicated the destruction of cellulose crystalline region. The IR analysis exhibited that thermal degradation of wood component was different depending upon the carbonization temperature. It can be suggested from the results that PEG with different molecular weights should be used for the conservation of excavated charred woods.

• Molecules and Cells
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• v.21 no.1
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• pp.34-41
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• 2006

The neuronal localization of alpha-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid (AMPA) glutamate receptor (GluR) subunits is vital as they play key roles in the regulation of calcium permeability. We have examined the distribution of the calcium permeable AMPA glutamate receptor subunit GluR1 in the mouse visual cortex immunocytochemically. We compared this distribution to that of the calcium-binding proteins calbindin D28K, calretinin, and parvalbumin, and of GABA. The highest density of GluR1-immunoreactive (IR) neurons was found in layers II/III. Enucleation appeared to have no effect on the distribution of GluR1-IR neurons. The labeled neurons varied in morphology; the majority were round or oval and no pyramidal cells were labeled by the antibody. Two-color immunofluorescence revealed that 26.27%, 10.65%, and 40.31% of the GluR1-IR cells also contained, respectively, calbindin D28K, calretinin, and parvalbumin. 20.74% of the GluR1-IR neurons also expressed GABA. These results indicate that many neurons that express calcium-permeable GluR1 also express calcium binding proteins. They also demonstrate that one fifth of the GluR1-IR neurons in the mouse visual cortex are GABAergic interneurons.

• Current Optics and Photonics
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• v.3 no.1
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• pp.8-15
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• 2019

We describe a common optical system that merges a LADAR system, which generates a point cloud, and a more traditional imaging system operating in the LWIR, which generates image data. The optimum diameter of the entrance pupil was determined by analysis of detection ranges of the LADAR sensor, and the result was applied to design a common optical system using LADAR sensors and LWIR sensors; the performance of these sensors was then evaluated. The minimum detectable signal of the $128{\times}128-pixel$ LADAR detector was calculated as 20.5 nW. The detection range of the LADAR optical system was calculated to be 1,000 m, and according to the results, the optimum diameter of the entrance pupil was determined to be 15.7 cm. The modulation transfer function (MTF) in relation to the diffraction limit of the designed common optical system was analyzed and, according to the results, the MTF of the LADAR optical system was 98.8% at the spatial frequency of 5 cycles per millimeter, while that of the LWIR optical system was 92.4% at the spatial frequency of 29 cycles per millimeter. The detection, recognition, and identification distances of the LWIR optical system were determined to be 5.12, 2.82, and 1.96 km, respectively.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.40-45
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• 2009

N-Alkylcarbazole-3-vinylene-2-methyl-4-dicyanomethylene-4H-pyran derivatives were synthesized by dehydration, $S_N2$, Vilsmeier, and Knoevenagel condensation. They are red-emitting materials for organic light emitting device (OLED) composed of electron donor of N-alkylcabazole-3-vinylene groups and electron acceptor of 2-methyl-4-dicyanomethylene-4H-pyran groups by a conjugated structure. The structural properties of reaction products were analyzed FT-IR and $^1H-NMR$ spectroscopy. The thermal stabilities and reactivities were measured by melting points and yields. The UV-visibles and PL properties can be determined by exitation spectra and emission spectra, respectively.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.248-250
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• 1990

Dichloro and ethylenediamine rhodium(III) complexes of a flexible $N_2O_2$-type tetradentate ligand, ethylenediamine-N,N'-di- -butyric acid(eddb), have been prepared. Both s-cis- and uns-cis geometrical isomers have been yielded in the $[Rh(eddb)Cl_2]-\;and\;[Rh(eddb)(en)]^+$ complexes. Ir, pmr, and electronic absorption spectra are used to characterize the complexes obtained in this work.

• Clinical and Experimental Pediatrics
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• v.63 no.3
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• pp.110-114
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• 2020

Background: Subclinical hypothyroidism (SH) is a common condition in obese children. However, its effect on glucose and lipid metabolism in obese children remains controversial. Purpose: The present study aimed to investigate the association between SH and metabolic parameters. Methods: A total of 215 obese children and adolescents aged 6-18 years were included in this retrospective cross-sectional study. The patients' anthropometric measurements such as thyrotropin (TSH), free thyroxine (fT4), fasting plasma glucose, and insulin levels, as well as homeostasis model assessment for insulin resistance (HOMA-IR) index, and lipid profiles were evaluated. The patients were allocated to the SH group (fT4 normal, TSH 5-10 mIU/L) (n=77) or the control group (fT4 normal, TSH<5 mIU/L) (n=138). The glucose and lipid metabolisms of the 2 groups were compared. Results: SH was identified in 77 of 215 patients (36%). Mean body mass index was similar in both groups. The mean serum insulin, HOMA-IR, and triglyceride (TG) levels were higher and the mean high-density lipoprotein cholesterol level was lower in the SH group than in the control group (P=0.007, P=0.004, P=0.01, and P=0.02, respectively). A positive correlation was observed between TSH level and insulin level, HOMA-IR, and TG level. Conclusion: SH was identified in some of the obese children and adolescents. A clear association was observed between SH, insulin resistance, and dyslipidemia in obese children.