http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Semi Yu,Enkhzaya Davaa,Gyeong-Rok Lee,Eun Joo Lee,Jeong-Sook Park 충남대학교 약학대학 의약품개발연구소 2012 藥學論文集 Vol.27 No.-
The objective of this study was to validate a reliable analytical method for the determination of rosiglitazone in human plasma by a semi-micro high performance liquid chromatography (HPLC) system with UV detection. Rosiglitazone was dissolved in methanol. Separation was performed on a SPcolumn C18 UG120 (4.6 mm × 150 mm) using mobile phase of acetonitrile, methanol and acetate buffer (pH 4.0) at a volume ratio of 20:10:70. The signals were monitored by UV detector at 214 nm with flow-rate of 1 ml/min. The intra- and inter-day precision expressed as the relative standard deviation was less than 15%. The retention time of rosiglitazone was 7.6 min. The detection limit of rosiglitazone in human plasma was 2 μg/ml and the limit of quantification was 5 μg/ml. The calibration curve was linear in the concentration range of 5~100 μg/ml (r2=0.999). The accuracy was from 1.0% to 13.5% while the intra-day and inter-day coefficient of variation of the same concentration range was less than 15%. This analytical method should be improved to be applied to determine rosiglitazone in human plasma.
Oh, Semi,Shin, Kyung-Sik,Kim, Sang-Woo,Lee, Sangbin,Yu, Hyeongwoo,Cho, Soohaeng,Kim, Kyoung-Kook American Scientific Publishers 2013 Journal of Nanoscience and Nanotechnology Vol.13 No.5
<P>The improvement of the optical output power of GaN-based light emitting diodes (LEDs) was achieved by employing nano-sized flat-top hexagonal ZnO rods. ZnO nanorods (NRs) with the average diameters of 250, 350, and 580 nm were grown on p-GaN top surfaces by a simple wet-chemical method at relatively low temperature (90 degrees C) to investigate the effect of the diameter of ZnO NRs on the light extraction efficiency. Consequently, the enhancement by the factor of as high as 2.63 in the light output intensity at 20 mA for the LED with 350 nm ZnO NRs was demonstrated without the increase in the operation voltage compared to the reference LED.</P>
Two-dimensional locomotion of a microrobot with a novel stationary electromagnetic actuation system
Choi, Hyunchul,Choi, Jongho,Jeong, Semi,Yu, Chungsun,Park, Jong-oh,Park, Sukho Institute of Physics Publishing 2009 Smart materials & structures Vol.18 No.11
<P>In this paper, we study the locomotion of a microrobot for intravascular therapy. As an intravascular microrobot has to be small, a conventional actuator, such as a micro-motor, and a battery cannot be integrated. To solve this integration problem, we analyze a microrobot with an electromagnetic actuation (EMA) system. Previously, an EMA system using two stationary coil pairs was proposed for the 2-dimensional (D) planar locomotion of a microrobot. The EMA system used two stationary pairs of Helmholtz coils and two stationary pairs of Maxwell coils in the <I>x</I>- and <I>y</I>-direction, respectively. This paper proposes a novel stationary EMA system using two pairs of Helmholtz coils and one pair of Maxwell coils. The 2D locomotion of the microrobot using the proposed EMA system is analyzed and verified by various experiments. The microrobot actuated by the proposed EMA system was able to move in the desired direction on the desired path. The comparison between the proposed EMA system and the previous EMA system showed that the proposed system had an 18% smaller volume and used 91% less coil current for the same actuation force than the previous EMA system. The proposed EMA system produced 2D locomotion of the microrobot, while having a small volume and a lower power consumption than the previous EMA system. </P>
새로운 전자기 구동 시스템을 이용한 2차원 평면 이동 마이크로 로봇
최현철(Hyunchul Choi),최종호(Jongho Choi),정세미(Semi Jeong),유충선(Chungsun Yu),박종오(Jongoh Park),박석호(Sukho Park) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5
In this study, we examined the locomotion using of intravascular therapy microrobot with novel stationary electromagnetic actuation system. Locomotion of the microrobot is very important in various function of microrobot. However, by th size limitation of microrobot cannot be integrated a conventional actuator and a battery. To solve the actuation problem, we consider the locomotion of the microrobot with an Electromagnetic Actuation (EMA) system. Previously, an EMA system using two stationary coil pairs was proposed for the 2D planar locomotion of the microrobot. The EMA system used two stationary pairs of Helmholtz coils and of Maxwell coils in the x-and y-direction. This study proposes a novel stationary EMA system using two pairs of Helmholtz coils and one pair of Maxwell coils. The proposed EMA system can produce 2D locomotion of the microrobot, while having a small system volume and low power consumption than previous EMA system.
Avenanthramide-C Restores Impaired Plasticity and Cognition in Alzheimer’s Disease Model Mice
Vijay Sankar Ramasamy,Manikandan Samidurai,Hyung Joon Park,Ming Wang,Ra Young Park,Seon Young Yu,Hee Kyung Kang,Semi Hong,Won-Seok Choi,Yu Young Lee,Hyung-Seok Kim,Jihoon Jo 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10
Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline and dementia with no effective treatment. Here, we investigated a novel compound from oats named avenanthramide-C (Avn-C), on AD-related memory impairment and behavioral deficits in transgenic mouse models. Acute hippocampal slices of wild-type or AD transgenic mice were treated with Avn-C in the presence or absence of oligomeric Aβ42. LTP analyses and immunoblotting were performed to assess the effect of Avn-C on Aβ-induced memory impairment. To further investigate the effect of Avn-C on impaired memory and Aβ pathology, two different AD transgenic mice (Tg2576 and 5XFAD) models were orally treated with either Avn-C or vehicle for 2 weeks. They were then assessed for the effect of the treatment on neuropathologies and behavioral impairments. Avn-C reversed impaired LTP in both ex vivo- and in vivo-treated AD mice hippocampus. Oral administration (6 mg/kg per day) for 2 weeks in AD mice leads to improved recognition and spatial memory, reduced caspase-3 cleavage, reversed neuroinflammation, and to accelerated glycogen synthase kinase-3β (pS9GSK-3β) and interleukin (IL-10) levels. Avn-C exerts its beneficial effects by binding to α1A adrenergic receptors to stimulate adenosine monophosphate-activated kinase (AMPK). All of the beneficial effects of Avn-C on LTP retrieval could be blocked by prazosin hydrochloride, a specific inhibitor of α1A adrenergic receptors. Our findings provide evidence, for the first time, that oats’ Avn-C reverses the AD-related memory and behavioral impairments, and establish it as a potential candidate for Alzheimer’s disease drug development.