Investigation of channel mobility in AlGaN/GaN high-electron-mobility transistors

Chang, Sung-Jae,Kang, Hee-Sung,Lee, Jae-Hoon,Yang, Jie,Bhuiyan, Maruf,Jo, Young-Woo,Cui, Sharon,Lee, Jung-Hee,Ma, Tso-Ping Institute of Pure and Applied Physics 2016 Japanese Journal of Applied Physics Vol.55 No.4

<P>We have investigated the channel mobility in the gated region of a set of high-quality AlGaN/GaN high-electron-mobility transistors (HEMTs). The resistances in the contact, access, and gated regions were extracted from straightforward I-D(V-G) measurements on sets of HEMTs with four different gate-to-drain distances. By correcting for the effects of the contact and access resistances, much more accurate effective mobility curves in the gated region, compared to those reported in the past, have been obtained. The maximum effective mobility in that region has been found to be 1100cm(2)V(-1) s(-1) at carrier density n(s) = 7 x 10(12)cm(-2) at room temperature. We have extracted the mobility curves in a wide range of temperatures (80 to 520 K) and carrier concentrations (up to 1.3 x 10(13)cm(-2)). Our systematic measurements have revealed various dominant scattering mechanisms as the temperature and carrier concentration change. (C) 2016 The Japan Society of Applied Physics</P>

중부지역 옥수수 파종기에 따른 생육단계 및 수량성 변화

서종호, 문중경, 정건호, 서민정, 구자환, 박장환, 배환희, 신성휴, 권영업 忠北大學校 農業科學硏究所 2014 農業科學硏究 Vol.30 No.2

Maize hybrids were planted on April 1, April 25, May 20 and June 15 in 2012, 2013 at the experimental paddy and upland fields in Suwon city , respectively to know changes of growth stage and yield according to different planting time. Maize planting on April 1 was not recommended because total growing days at planting on April 1 was not different with that at planting on April 25 due to many days from planting to emergence over 20 days at planting on April 1. Total growing days were not much different among three planting time after April 25 because days from silking to maturity was lengthened though days from planting to silking was shortened at later planting time. Stalk weight was decreased as planting time was delayed, particularly at planting times after May 20 at paddy field by excess water injury during early growth stage. But, grain yield was not low as in May and June. It is needed to introduce early maturity maize variety as Yanganok at late planting for higher grain yield and enough time for soil preparation for next winter crops

인삼 사포닌이 하부요로와 음경해면체 평활근의 이완작용에 미치는 효과

정희창,오태희 영남대학교 의과대학 2006 Yeungnam University Journal of Medicine Vol.23 No.1

이상의 결과를 종합하면, 인삼 총사포닌은 본 실험의 조건에서 배뇨개선 효과가 있으며 이에 관여하는 총사포닌의 주 효능은 근위부요도를 이환시킴으로써 이루어지는 것으로 생각된다. 그리고 인삼 총사포닌은 혈류역동학적으로 안전하게 음경해면체 평활근을 이완시켜 음경발기를 유발시키는 것으로 생각된다. Background: Korean ginseng (KG) has been used as a general tonic, and for voiding dysfunction for a long time in oriental society. However, scientific basic studies on the use of KG, have been rare, especially for voiding and erectile dysfunction. This study was performed to investigate the effects of KG on voiding and erectile function by examining the effects of total saponin (TS) on the bladder, urethral and penile cavernosal smooth muscle. Materials and methods: To examine the effects of TS, NewZeland white rabbits were used to obtain tissue strips from the smooth muscle of the bladder, proximal urethra and corpus cavernosum. Adult Spargue Dawley rats were used to examine the changes in urodynamic findings and penile erection after administration of TS. Results: In proximal urethral strips, the rate of relaxation of the proximal urethra was increased from 9.0±2.9 to 33.7±4.8% in a dose-dependent manner when the concentration of TS was added accumulatively from 0.25 mg/ml to 4.0 ng/ml (p<0.05). However, no significant response was observed in the bladder strips within these concentration ranges. For the corpus cavernosal strips, the rate of relaxation ranged from 5.8±2.1 to 36.7±5.8%, increasing in a dose-dependent manner when TS was increased from 1.0 mg/ml to 4.0 mg/ml (p<0.05). After administration of 0.1 ml of TS (32 mg/ml) in the rat, the bladder pressure was 37.5±8.5 mmHg at 52.1±7.0 sec. during isovolumetric bladder contraction, showing no significant differences from 35.7±7.8 mmHg and 50.7±7.2 sec, respectively, before treatment. However, when 0.1 ml of TS (32 mg/ml) was administered, the relative reduction of urethral pressure was 6.9±0.5 mmHg at 62±7.5 sec, which was significantly higher compared to 4.6±1.1 mmHg at 45±10 sec before treatment (p<0.05). For the cavernosal injection study, the change in intracavernosal pressure (△ICP) was examined after administering 0.1 ml of TS. The cumulative additions of TS at concentrations from 0.5 mg/ml to 32 mg/ml increased △ICP from 1.3±0.5 to 21.3±7.8 mmHg in a dose-dependent manner (p<0.05). The duration of tumescence was from 0.3±0.1 to 5.2±0.2 min, showing dose-dependent increase (p<0.05). Furthermore, the cumulative addition of TS at concentrations from 0.5 mg/ml upto 32 mg/ml did not cause any significant change in systemic blood pressure. Conclusion: These results suggest that ginseng improves voiding functions, which is mainly achieved by TS relaxing the proximal urethra, the most important part of the bladder outlet function. In addition, ginseng safely induced a penile erection hemodynamically by relaxing the corpus cavernosum.

S-580 : Vitamin D and carotid subclinical atherosclerosis in SLE

( Chang Bum Bae ),( Ju Yang Jung ),( Bo Ram Go ),( Hyun Ah Kim ),( Chang Hee Suh ) 대한내과학회 2013 대한내과학회 추계학술대회 Vol.2013 No.1

Vitamin D and carotid subclinical atherosclerosis in SLE Chang-Bum Bae, Ju-Yang Jung, Bo-ram Go, Hyun-Ah Kim, Chang-Hee Suh Department of Rheumatology, Ajou University School of Medicine, Suwon, Korea Introduction Atherosclerosis develops earlier in systemic lupus erythematosus (SLE) and is the important cause of mortality. It has been suggested that vitamin D deficiency contributed cardiovascular disease and immune dysregulation in SLE. Methods One-hundred two female patients with SLE and 52 normal controls (NC) were recruited. The carotid artery intima-media thickness (cIMT) and plague were assessed by B-mode ultrasound at the carotid artery level. Vitamin 25(OH)D3 levels were checked by immunoradiometric assay using the Bio-Line 25(OH)D3-Ria CT kit (Bio-Line S.A., Belgium). Disease activity markers were checked at the time of enrollment. Results The cIMT of SLE is 0.41±0.08mm, which is higher than NC (0.37±0.11 mm, p=0.012). Also, carotid artery plague index (PI) of SLE is higher than NC (0.68±1.39 vs 0.26±0.87, p=0.026). The cIMT was correlated with age (r=0.442, p<0.001), body mass index (r=0.246, p=0.013), waist-hip ratio (r=0.245, p=0.013), SLE disease activity index (r=0.239, p=0.016), taking aspirin (r=0.244, p=0.013), and the carotid artery PI was correlated with renal involvement (r=0.224, p=0.023) in patients with SLE. Vitamin 25(OH)D3 was not showed correlation with cIMT and carotid artery PI. Also, it was not correlated with disease activity markers. Conclusion In patients with SLE, the risk of cardiovascular disease measured by cIMT and carotid artery plaque was higher than NC, which may be derived from systemic inflammation. However, vitamin D levels were not showed significant correlations with carotid subclinical atherosclerosis. It may be not suitable to assess vitamin D as marker of disease activity or subclinical atherosclerosis.

만성 승모판 패쇄부전증 환자에서의 안지오텐신 전환효소 억제제의 장기 투여 효과

김대희,이명묵,이해영,조현재,박승정,서재빈,서정원,양한모,윤창환,조상호,이준희,김용진,김명아,손대원,오병희,박영배 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.2

췌장염에 의한 가성낭종내에 생긴 가성동맥류 : 1례 보고

오연희,이채경,김승현,이성우,양창현,이정호,이영현 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

만성 췌장염의 합병증으로 생긴 가성동맥류는 드문질환으로, 반복적으로 다량의 출혈을 일으킬 수 있으며, 치료를 하지 않을 경우 사망율이 높기 때문에, 조기 진단과 치료가 필수적이다. 저자들은 38세 남자 환자에서 췌장염의 합병증으로 생긴 가성낭종내에서 발생한 가성동맥류 1예를 경험하였기에 보고하는 바이다. 가성 동맥류의 색혈류도플러상 낭종내에 양방향 흐름의 와류를 볼 수 있었다. Pancreatic Pseudoaneurysm within Pseudocyst from Pancreatitis: 1 Case Department of Diagnostic Radiology and Internal Medicine, College of Medicine,DongGuk University Yeon Hee OH M.D., Chae Kyeong Lee M.D., Seoung Hyeon Kim M.D., Sung Woo Lee M.D., Chang Heon Yang M.D., Jung Ho Lee M.D., Young Hyun Lee M.D. Pseudoaneurysm from pancreatitis is uncommon, but it can cause recurrent and massive hemorrhage. Because of high morbidity and mortality, early detection and treatment of the pseudoaneurysm is needed. We report a case of pseudoaneurysm within pseudocyst from pancreatitis. Color-flow Doppler sonography shows bidirectional flow and turbulent arterial flow, within anechoic mass.

Gene flow of GM pepper

Sun-Hee Shin,Min Jung,Jung-Mi Park,Eun-Mi Jeon,Chang-Gi Kim,Chee-Hark Harn 한국육종학회 2013 한국육종학회 심포지엄 Vol.2013 No.07

CMVP1 (cucumber mosaic virus pathotype 1) has been frequently occurring virus causing damage in pepper farms, and it is hard to control the outbreak due to lack of the genetic source resistant to this specific pathotype. Therefore, we have developed transgenic peppers tolerant of CMVP1 using a CP gene of CMVP0 pathogen. In order to fulfill the requirement of the biosafety assessment criteria, we have studied the horizontal gene flow from GM pepper to non-GM pepper by monitoring the transgene movement. If the pepper farms are located closely each other and the pollen moves from GM pepper to non-GM pepper, it would cause unintended fertilization. Therefore, a buffer zone to separate the cultivation regions is required to avoid the contamination of transgene. Previously, several data regarding the movement distance of pepper pollen were reported by judging the phenotypic change. However, no tool as a trace marker was available. The objective of this study was to assess the frequencies of gene flow from GM peppers to non-GM peppers in neighboring farms using the transgene of CP as a trace marker. The GM and non-GM peppers were cultivated in the isolated farm of Nongwoo Bio Co. (NW GM pepper field) and pepper fruits were collected from the NW GM pepper field as well as the neighboring pepper farms. The pepper seeds collected from the farms were planted and the massive PCR analysis was performed to answer the question how far the pollen of GM pepper migrates. The conclusive data based on the consecutive experiments for 6 years is that the gene flow by pollen movement did not occur in peppers that were separated each other over 30 m.

Gene Expression Analysis of the Bromobenzene Treated Liver with Non-hepatotoxic Doses in Mice

Lim, Jung-Sun,Jeong, Sun-Young,Hwang, Ji-Yoon,Park, Han-Jin,Cho, Jae-Woo,Song, Chang-Woo,Kim, Yang-Seok,Lee, Wan-Seon,Moon, Jin-Hee,Han, Sang-Seop,Yoon, Seok-Joo The Korean Society of Toxicogenomics and Toxicopro 2005 Molecular & cellular toxicology Vol.1 No.4

Bromobenzene (BB) is well known hepatotoxicant. Also, BB is an industrial solvent that arouses toxicity predominantly in the liver where it causes centrilobular necrosis. BB is subjected to Cytochrome P450 mediated epoxidation followed by either conjugation with glutathione, enzymatic hydrolysis or further oxidation. In this study, we focused on BB-induced gene expression at non-hepatotoxic dose. Mice were exposed to two levels of BB, sampled at 24 h, and hepatic gene expression levels were determined to evaluate dose dependent changes. When examining the toxic dose of BB treated group in other previous studies, genes related to heat shock protein, oxidative stress, and drug metabolism are expressed. Compared to these results, our study, in which non-toxic dose of BB was administrated, showed similar patterns as the toxic conditions above. The purpose of the study was to select genes that showed changes in relation to the differing dose through confirmation of the difference within transcriptomic boundaries, but those that are not detected by the existing classic toxicology tools in non-hepatotoxic dose.

냉기 치료에 따른 둔근에서의 피부 및 근육내 온도 변화

정우성,김미정,박시복,이상건,김영호,양길태,장윤희 大韓再活醫學會 1998 Annals of Rehabilitation Medicine Vol.22 No.2

Cerebral vascular burden on hippocampal subfields in first-onset drug-naïve subjects with late-onset depression

Choi, Woo Hee,Jung, Won Sang,Um, Yoo Hyun,Lee, Chang Uk,Park, Young Ha,Lim, Hyun Kook Elsevier 2017 Journal of affective disorders Vol.208 No.-

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>Although there is substantial evidence of associations between frontal-striatal circuits and cerebral vascular burden in late-onset depression (LOD), relationships between vascular burden and hippocampal subfields are not clear. The purpose of this study was to investigate relationships between cerebral vascular burden and hippocampal subfield volume in LOD patients.</P> <P><B>Methods</B></P> <P>Fifty subjects with LOD and 50 group-matched healthy control subjects underwent magnetic resonance imaging scanning. Hippocampal subfields volumes were measured and compared between the groups. In addition, association patterns between white matter hyperintensity (WMH) volumes, clinical measures and hippocampal subfield volumes were investigated in the LOD group.</P> <P><B>Results</B></P> <P>Subjects with LOD exhibited significant hippocampal volume reductions in the total hippocampus, cornu ammonis (CA) 1 and 3 and dentate gyrus (DG) areas compared with healthy subjects. Total WMH volume was negatively correlated with left total hippocampal volume and CA1 in the LOD group. In addition, depression severity was negatively associated with left and right CA3 volumes in the LOD group.</P> <P><B>Limitation</B></P> <P>Our findings of distinctive relationships between WMH and hippocampal subfields demonstrate a simple correlation, but do not prove causation</P> <P><B>Conclusion</B></P> <P>This study is the first to elaborate distinctive association patterns between hippocampal subfield volumes and cerebral vascular burden in LOD. These structural changes in the hippocampal CA1, CA3 and DG areas might be at the core of the underlying neurobiological mechanisms of hippocampal dysfunction in LOD. However, longitudinal studies will be needed to identify the mechanisms of these structural changes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This study is the first to elaborate distinctive association patterns between hippocampal subfield volumes and cerebral vascular burden in LOD. </LI> <LI> White matter hyperintensity was negatively correlated with left total hippocampal volume and CA1 in the LOD group. </LI> <LI> In addition, depression severity was negatively associated with left and right CA3 volumes in the LOD group. </LI> </UL> </P>