In-line 마그네트론 스퍼터 장치를 사용하여 산소 분위기에서 제작한 Ag 박막의 특성

구대영,김원목,조상무,황만수,이인규,정병기,이택성,이경석,조성훈,Ku, Dae-Young,Kim, Won-Mok,Cho, Sang-Moo,Hwang, Man-Soo,Lee, In-Kyu,Cheong, Byung-Ki,Lee, Taek-Sung,Lee, Kyeong-Seok,Cho, Sung-Hun 한국재료학회 2002 한국재료학회지 Vol.12 No.8

A study was made to examine the electrical, compositional, structural and morphological properties of Ag thin films deposited by DC magnetron sputtering in $O_2$ atmosphere with deposition temperature from room temperature to 15$0^{\circ}C$ using in-line sputter system. The Ag films deposited at temperature above $100^{\circ}C$ in oxygen atmosphere gave a similar specific resistivity to and even lower oxygen content than those deposited using pure Ar sputter gas The Ag films deposited with pure Ar gas was mainly composed of crystallites with [111] preferred orientation, while, for those deposited in oxygen atmosphere, more than 50% of the volume was composed of crystallites with [100] orientation. The difference in the micro structure did not cause any difference in the specific resistivity of Ag films. The results showed that the transparent conducting oxide films and the Ag films could be processed sequentially in the same deposition chamber with careful control of deposition temperature, which might result in a cost reduction for constructing the large scale in-line deposition system.

Comprehensive Evaluation of the NeoBase 2 Non-derivatized MSMS Assay and Exploration of Analytes With Significantly Different Concentrations Between Term and Preterm Neonates

Lee Beomki,Heo Won Young,Kim Jee Ah,Lee Hyun-Seung,Hwang Narae,Park Hyung-Doo,Sung Se In,Chang Yun Sil,Park Won Soon,Lee Soo-Youn 대한진단검사의학회 2023 Annals of Laboratory Medicine Vol.43 No.2

Background: Despite the popularity of the NeoBase 2 Non-derivatized MSMS assay (PerkinElmer, Turku, Finland), there are no reports of its comprehensive evaluation, including the ability to distinguish transient tyrosinemia of the newborn (TTN) from tyrosinemia type 1 (TYR 1) using succinylacetone (SUAC). No newborn screening (NBS) cutoffs for preterm neonates in the Korean population have been suggested. We evaluated the NeoBase 2 assay and identified analytes requiring different cutoffs in preterm neonates. Methods: Residual NBS dried blood spot samples and proficiency testing (PT) materials of the Newborn Screening Quality Assurance Program and the Korean Association of External Quality Assessment Service were used. Precision, accuracy, limit of detection (LOD), lower limit of quantification (LLOQ), linearity, recovery, carryover, and performance of SUAC were evaluated. Cutoffs were determined, and analytes requiring different cutoffs in preterm neonates were investigated. Results: Mean CVs for within-run and between-day precision were within 15%. Accuracy analysis indicated high agreement with in-house derivatized assay results and results of other PT participants. All analytes demonstrated acceptable LOD, LLOQ, and linearity. Recoveries were acceptable, except for SUAC. Carryover was negligible. Cutoffs were established for all analytes; Tyr, adenosine, and C20:0-lysophosphatidylcholine required different cutoffs in preterm neonates. Differential diagnosis of TYR 1 and TTN was successful with simultaneous Tyr and SUAC measurement. Conclusions: The NeoBase 2 assay demonstrated satisfactory performance. The additional analytes provide a wider diagnostic coverage, and the simultaneous measurement of Tyr and SUAC is efficient in excluding TYR 1. The new cutoffs for preterm neonates may decrease false-positive rates, without compromising diagnostic sensitivity.

Discriminative detection of indoor volatile organic compounds using a sensor array based on pure and Fe-doped In₂O₃ nanofibers

Lee, Chul-Soon,Li, Hua-Yao,Kim, Bo-Young,Jo, Young-Moo,Byun, Hyung-Gi,Hwang, In-Sung,Abdel-Hady, Faissal,Wazzan, Abdulaziz A.,Lee, Jong-Heun Elsevier 2019 Sensors and actuators. B Chemical Vol.285 No.-

<P><B>Abstract</B></P> <P>Representative indoor volatile organic compounds (VOCs) such as benzene, xylene, toluene, formaldehyde, and ethanol need to be detected in a highly sensitive and discriminative manner because of their different impact on human health. In this study, pure and 0.05, 0.1, 0.3, and 0.5 at% Fe-doped In<SUB>2</SUB>O<SUB>3</SUB> nanofibers were prepared by electrospinning and their gas sensing characteristics toward the aforementioned VOCs were investigated. The doping of In<SUB>2</SUB>O<SUB>3</SUB> nanofiber sensor with 0.05 and 0.1 at% Fe shifted the temperature to show the maximum responses to benzene, xylene, and toluene, and reduced responses to ethanol and formaldehyde, thus demonstrating changed gas selectivity. The gas sensing characteristics of 0.5 at% Fe-doped In<SUB>2</SUB>O<SUB>3</SUB> nanofiber sensor were substantially different from those of the other sensors. Significantly different gas sensing patterns of pure and Fe-doped In<SUB>2</SUB>O<SUB>3</SUB> sensors could be used to discriminate between the five different VOCs at 375 °C and to distinguish between the aromatic and non-aromatic gases at all sensing temperatures. The mechanism underlying the Fe-induced change in gas sensing characteristics has been discussed in relation to the variation of catalytic activity, morphology, oxygen adsorption, and charge carrier concentration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fabrication of a sensor array using pure and Fe-doped In<SUB>2</SUB>O<SUB>3</SUB> nanofibers. </LI> <LI> Discriminative detection of benzene, xylene, toluene, ethanol, and formaldehyde. </LI> <LI> Distinction between aromatic and non-aromatic indoor pollutants using sensor array. </LI> <LI> Gas sensing mechanism underlying Fe-induced change in response and selectivity. </LI> </UL> </P>

Genetic diversity for gliadin subunits of Korean and Tunisian wheat

Sang Heon Kim,Yong Jin Lee,Man Bo Lee,Yacoubi Inès,Hansu Kim,Cheolwon Lee,Yong Weon Seo 한국육종학회 2014 한국육종학회 심포지엄 Vol.2014 No.07

Gliadins are the main class of wheat seed storage proteins. Since gliadins show a high level of polymorphism as well as genetically fixed, it can be used as a marker for the genetic identification. Gliadin subunit diversity information can be useful for wheat quality breeding programs. Tunisia is a country in the North Africa bordered with the Mediterranean Sea to the north and the east but with the Sahara desert to the south, which represent extremely different growth climate. Therefore, there may be a numerous variation in Tunisian common wheat and durum wheat. Total 48 lines of wheat consisted of 32 common wheat (16 Korean wheat and 16 Tunisian common wheat) and 16 Tunisian durum wheat were incorporated in this study. Gliadins were extracted with 70% ethanol and fractionated by acid polyacrylamide gel electrophoresis (A-PAGE) at 8% in aluminum lactate buffer (pH 3.1). The gel was stained with 0.25% Coomassie Brilliant Blue (CBB) R-250. The presence of each gliadin subunit band was scored and cluster analysis was carried out. The cluster showed that wheat varieties were classified into some groups and their genetic distance could be identified. The obtained information will be helpful to the future breeding program of tetraploid durum wheat as well as hexaploid common wheats. Acknowledgement: This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2012K1A3A1A09028123) and carried out with the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project title: Development of high yielding wheat with stress tolerance via molecular breeding strategies, Project No. PJ008031)”, Rural Development Administration, Republic of Korea.

cuiD Is a Crucial Gene for Survival at High Copper Environment in Salmonella enterica Serovar Typhimurium

Sung-Young Lim,Min-Ho Joe,Sang-Sun Song,Mun-Hee Lee,John W. Foster,박용근,Soon Yong Choi,In Soo Lee 한국분자세포생물학회 2002 Molecules and cells Vol.14 No.2

Copper ion is an essential micronutrient but it is also extremely cytotoxic when it exists in excess. Our stud-ies have shown that Salmonella enterica serovar Ty-phimurium can survive potentially lethal copper expo-sures by the way of copper efflux system. A copper ion inducible gene was identified in virulent S. typhi-murium by using the technique of MudJ (Km, lac)-directed lacZYA operon fusions. A copper ion inducible strain LF153 (cuiD::MudJ) has been identified. The cuiD mutant exhibits a copper sensitive phenotype but possesses normal resistance to other metal ions, and lost DMP oxidase activity. Therefore, we suggest that cuiD is an important gene for copper homeostasis and the copper resistance response. The copper sensitive phenotype was complemented by pYL3.0 carrying cuiD+. Sequence analysis showed cuiD contains 1,614 bp encoding a 536 amino acid with a 27 amino acid signal peptide and a 509 amino acid residues compris-ing the mature peptide. The CuiD shows 81% homol-ogy to YacK, a putative multicopper oxidases which extrudes copper in Escherichia coli. This ORF contains four conserved regions that contain 12 copper ligands (types 1, 2, and 3) present in various copper homeosta-sis responsible proteins. The H2O2 sensitive phenotype of the cuiD mutant indicates that cuiD may be in-volved in oxidative stress response.

Recurrent thrombosis after endovascular treatment for malignant superior vena cava syndrome

( Sang Ho Lee ),( Sun Young Kim ),( Heung Tae Kim ),( Chang Woo Shim ),( Ho Seok Chi ),( Hye In Lee ),( Do Il Choi ),( Hyun Bum Kim ),( In Jun Lee ) 대한내과학회 2015 대한내과학회 추계학술대회 Vol.2015 No.1

Endovascular treatment (EVT) including angioplasty and stenting is an effective treatment for superior vena cava (SVC) syndrome. Recurrence of SVC syndrome is mainly caused by tumor progression and occurs in around 20% after EVT, but sometimes venous thrombosis within stent accounts for recurrence of SVC syndrome. Anticoagulation after EVT is still a controversial issue. In our case, a 73 year-old man with SVC syndrome caused by mediastinal lymph node metastasis from non-small cell lung cancer underwent EVT followed by anticoagulation with low molecular weight heparin (LMWH), but symptomatic progression due to in-stent thrombosis necessitated the second procedure after two weeks. A total of 4 sessions of EVT and anticoagulation with LMWH, warfarin and rivaroxaban did not induce durable resolution of in-stent thrombosis. The 4th EVT was done with stent -graft, but computed tomography after the last procedure revealed remained thrombus in SVC and newly developed pulmonary thromboembolism during warfarinization. Our case suggests refractory in-stent thrombosis could develop despite of anticoagulation after EVT for SVC syndrome.

In-depth considerations for better polyelectrolytes as interfacial materials in polymer solar cells

Yeo, Jun-Seok,Kang, Minji,Jung, Yen-Sook,Kang, Rira,Lee, Seung-Hoon,Heo, Youn-Jung,Jin, Sung-Ho,Kim, Dong-Yu,Na, Seok-In Elsevier 2016 Nano energy Vol.21 No.-

<P><B>Abstract</B></P> <P>We perform a comprehensive study to achieve better polyelectrolytes (PEs) as electron-transport layers (ETLs) in polymer solar cells (PSCs). Three well-known PEs – PFN, PEIE, and WPF – are chosen as model systems and investigated with variations in their backbone structures and the state of the amine functionalities on their side chains. Respectively optimized PSCs using the three PEs exhibit different cell-performances, mainly owing to the diode characteristics of built-in potential and recombination strength. To identify how such deviated device-performances correlate with the structural features of PEs, the modulated interfaces of ITO/PEs and PEs/active layer are studied in detail. It is found that conjugated backbones and larger counter-anions on side chains can promote the modulation of ITO work functions (WFs) and that a large amount of protonated amines on PEs is beneficial for junction properties with a subsequent active layer. Additionally, our results indicate that interfacial dipole and electrical doping between the PE and active layer, in addition to WF modulation of the ITO cathode, are important for device efficiency. Accordingly, with the aid of the molecular features of PEIE, PEIE-PSCs exhibit excellent device efficiency and stability compared with PFN- and WPF-PSCs. In the PTB7-th:PC<SUB>71</SUB>BM system, a remarkable power-conversion efficiency of 9.97% is achieved with a single PEIE ETL.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chemical structure and performance of polyelectrolytes (PEs) in PSCs are correlated. </LI> <LI> Interfacial dipole and doping between PEs and active layer lead to efficient PSCs. </LI> <LI> PEIE-based PSCs have excellent device efficiency and high stability. </LI> <LI> Especially, in the PTB7-th system, encouraging efficiency of 9.97% is achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

<i>In vitro</i> and <i>in vivo</i> evaluation of a novel polymer-free everolimus-eluting stent by nitrogen-doped titanium dioxide film deposition

Park, Dae Sung,Bae, In-Ho,Jeong, Myung Ho,Lim, Kyung Seob,Sim, Doo Sun,Hong, Young Joon,Lee, So-Youn,Jang, Eun Jae,Shim, Jae-Won,Park, Jun-Kyu,Lim, Han Chul,Kim, Han Byul Elsevier 2018 Materials Science and Engineering C Vol.91 No.-

<P><B>Abstract</B></P> <P>Inflammation and thrombosis are linked to the use of polymer-based drug-eluting stents (DES). The aim of this study was to develop a polymer-free everolimus (EVL)-eluting stent using nitrogen-doped titanium dioxide (N-TiO<SUB>2</SUB>) and verify its efficacy by <I>in vitro</I> and <I>in vivo</I> assessment in a porcine coronary model. Various analytical approaches such as scanning electron microscopy and atomic force microscopy, electron spectroscopy, Fourier transform infrared spectrometry and contact angle measurement were employed for the characterization. As a part of biocompatibility assessment, platelet adhesion and smooth muscle cell (SMC) proliferation were examined. Bare metal stent (BMS), N-TiO<SUB>2</SUB> stent, everolimus-eluting N-TiO<SUB>2</SUB> (N-TiO<SUB>2</SUB>-EVL) stent, and commercialized EVL-eluting stent (EES) were randomly placed in forty coronary arteries in twenty pigs. After four weeks of implantation, the stents were subjected to histological and quantitative analysis. The N-TiO<SUB>2</SUB> film used in this study was well coated without any cracks or peeling. Surface hydrophilicity (88.8% of angle decrement) could be associated with the decrease in surface roughness post N-TiO<SUB>2</SUB> deposition (37.0%). The platelet adhesion on the N-TiO<SUB>2</SUB> surfaces was less than that on the BMS surface. The proliferation of SMC was suppressed in the N-TiO<SUB>2</SUB>-EVL group (30.2%) but not in the BMS group. In the animal study, the percent area restenosis was significantly decreased in the N-TiO<SUB>2</SUB>-EVL group compared to that in the BMS group. The results (BMS; 47.0 ± 11.00%, N-TiO<SUB>2</SUB>-EVL; 31.7 ± 10.50%, and EES; 29.1 ± 11.21%, <I>n</I> = 10, <I>p</I> < 0.05) were almost at par with those of the commercialized EVL-eluting stent. The introduction of N-TiO<SUB>2</SUB> deposition during fabrication of polymer-free DES may be an efficient accessorial process for preventing in-stent restenosis and thrombosis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> N-TiO<SUB>2</SUB> surfaces can help to reduce the platelet adhesion. </LI> <LI> In porcine model, N-TiO<SUB>2</SUB> everolimus decreased in-stent restenosis and fibrin deposition. </LI> </UL> </P>

Design and Analysis of CMOS-Compatible III-V Compound Electron-Hole Bilayer Tunneling Field-Effect Transistor for Ultra-Low-Power Applications

Kim, Sung Yoon,Seo, Jae Hwa,Yoon, Young Jun,Lee, Ho-Young,Lee, Seong Min,Cho, Seongjae,Kang, In Man American Scientific Publishers 2015 Journal of nanoscience and nanotechnology Vol.15 No.10

<P>In this work, we design and analyze complementary metal-oxide-semiconductor (CMOS)-compatible III-V compound electron hole bilayer (EHB) tunneling field-effect transistors (TFETs) by using two-dimensional (2D) technology computer-aided design (TCAD) simulations. A recently proposed EHB TFET exploits a bias-induced band-to-band tunneling (BTBT) across the electron hole bilayer by an electric field from the top and bottom gates. This is in contrast to conventional planar p(+)-p(-)-n TFETs, which utilize BTBT across the source-to-channel junction. We applied III-V compound semiconductor materials to the EHB TFETs in order to enhance the current drivability and switching performance. Devices based on various compound semiconductor materials have been designed and analyzed in terms of their primary DC characteristics. In addition, the operational principles were validated by close examination of the electron concentrations and energy-band diagrams under various operation conditions. The simulation results of the optimally designed In0.53Ga0.47As EHB TFET show outstanding performance, with an on-state current (I-on) of 249.5 mu A/mu m, subthreshold swing (S) of 11.4 mV/dec, and threshold voltage (V-th) of 50 mV at V-DS = 0.5 V. Based on the DC-optimized InGaAs EHB TFET, the CMOS inverter circuit was simulated in views of static and dynamic behaviors of the p-channel device with exchanges between top and bottom gates or between source and drain electrodes maintaining the device structure.</P>

Regulation of Hepatic Gluconeogenesis by an ER-Bound Transcription Factor, CREBH

Lee, Min-Woo,Chanda, Dipanjan,Yang, Jianqi,Oh, Hyunhee,Kim, Su Sung,Yoon, Young-Sil,Hong, Sungpyo,Park, Keun-Gyu,Lee, In-Kyu,Choi, Cheol Soo,Hanson, Richard W.,Choi, Hueng-Sik,Koo, Seung-Hoi Elsevier 2010 Cell metabolism Vol.11 No.4

<P><B>Summary</B></P><P>Endoplasmic reticulum (ER)-bound transcription factor families are shown to be involved in the control of various metabolic pathways. Here, we report a critical function of ER-bound transcription factor, CREBH, in the regulation of hepatic gluconeogenesis. Expression of CREBH is markedly induced by fasting or in the insulin-resistant state in rodents in a dexamethasone- and PGC-1α-dependent manner, which results in the accumulation of active nuclear form of CREBH (CREBH-N). Overexpression of constitutively active CREBH activates transcription of <I>PEPCK-C</I> or <I>G6Pase</I> by binding to its enhancer site that is distinct from the well-characterized CREB/CRTC2 regulatory sequences in vivo. Of interest, knockdown of CREBH in liver significantly reduces blood glucose levels without altering expression of genes involved in the ER stress signaling cascades in mice. These data suggest a crucial role for CREBH in the regulation of hepatic glucose metabolism in mammals.</P> <P><B>Highlights</B></P><P>► PGC-1α/GR activates CREBH expression under fasting or insulin-resistant conditions ► CREBH enhances hepatic gluconeogenesis via a CRTC2-dependent manner ► Depletion of CREBH in the liver ameliorates fasting hyperglycemia in diabetic mice</P>