Inhibition of Organic Anion Transporting Polypeptide 1B1 and 1B3 by Betulinic Acid: Effects of Preincubation and Albumin in the Media

Oh, Yunseok,Jeong, Yoo-Seong,Kim, Min-Soo,Min, Jee Sun,Ryoo, Gongmi,Park, Ji Eun,Jun, Yearin,Song, Yoo-Kyung,Chun, Se-Eun,Han, Songhee,Bae, Soo Kyung,Chung, Suk-Jae,Lee, Wooin John WileySons, Ltd 2018 Journal of Pharmaceutical Sciences Vol.107 No.6

<P>Betulinic acid (BA), a plant-derived pentacyclic triterpenoid, may interact with the members of the organic anion transporting polypeptide 1B subfamily. Here, we investigated the interactions of BA and its analogs with OATP1B1/3 and rat Oatp1b2 in vitro and in vivo. BA inhibited the activity of OATP1B1/3 and rat Oatp1b2 in vitro. Systemic exposure of atorvastatin was substantially altered with the intravenous co-administration of BA (20 mg/kg). Preincubation (incubation with inhibitors, followed by washout) with BA led to a sustained inhibition of OATP1B3, which recovered rapidly in the media containing 10% fetal bovine serum. The addition of albumin to the media decreased intracellular concentrations of BA and expedited the recovery of OATP1B3 activity following preincubation. For asunaprevir and cyclosporin A (previously known to inhibit OATP1B3 upon preincubation), the addition of albumin to the media shortened recovery time with asunaprevir, but not with cyclosporin A. Overall, our results showed that BA inhibits OATP1B transporters in vitro and may incur hepatic transporter-mediated drug interactions in vivo. Our results identify BA as another OATP1B3 inhibitor with preincubation effect and suggest that the preincubation effect and its duration is impacted by altered equilibrium of inhibitors between intracellular and extracellular space (e.g., albumin in the media). (C) 2018 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.</P>

Blurry 클래스 증분 학습 환경에서의 효율적인 프롬프트 학습 방법

오윤석(Yunseok Oh),최동완(DongWan Choi) Korean Institute of Information Scientists and Eng 2023 한국정보과학회 학술발표논문집 Vol.2023 No.12

안드로이드 스마트폰의 메모리 부족 및 부팅 특성 모니터링 기법

오윤석 ( Yunseok Oh ),안우현 ( Woo Hyun Ahn ) 한국정보처리학회 2016 한국정보처리학회 학술대회논문집 Vol.23 No.1

안드로이드 스마트폰의 성능을 향상시키기 위해서는 스마트폰 및 앱의 특성을 추출하는 것이 중요하다. 본 논문은 효율적인 메모리 관리를 위한 전단계로써 메모리 부족 및 부팅 특성을 모니터링 하는 AppMemTracker 앱을 제작하였다. 이 앱에 구현된 백그라운드 서비스들이 메모리 부족 및 부팅 특성에 관련된 정보를 추출하여 주기적으로 우리의 메일에 전송한다. AppMemTracker가 정확하게 동작하는지를 확인하기 위해 여러 스마트폰과 안드로이드 버전에서 실험 하였고, 정확한 정보가 추출되는 것을 확인하였다.

안드로이드 운영체제에서 프로세스의 상태 분류 및 분석

오윤석 ( Yunseok Oh ),안우현 ( Woo Hyun Ahn ) 한국정보처리학회 2016 한국정보처리학회 학술대회논문집 Vol.23 No.1

안드로이드 스마트폰의 효율적인 메모리 관리 연구를 위해서 기존 정책을 정확하게 분석해야 한다. 현재 안드로이드는 메모리가 부족하면 프로세스 우선순위(ADJ)가 낮은 것부터 제거하여 공간을 확보한다. 본 논문은 프로세스의 상태에 따라 어떤 ADJ 값을 가지는지 실행 시나리오를 통해 자세히 설명한다. 우리는 프로세스의 상태 분류를 위해 안드로이드 프레임워크 코드를 분석하였다.

웹 기반 움직이는 GIF 제작 서비스

오윤석(Yunseok Oh),이정민(Jeongmin Lee) 한국정보과학회 2021 한국정보과학회 학술발표논문집 Vol.2021 No.6

Short Communication : Hybrid laparoscopic myomectomy: A novel technique

( Yunseok Yang ),( Chanhee Jin ),( Kwoanyoung Oh ),( Joonsuk Park ) 대한산부인과학회 2015 Obstetrics & Gynecology Science Vol.58 No.5

The objective of this study was to report on a new surgical technique, hybrid laparoscopic myomectomy that integratesthe advantages of transumbilical laparoendoscopic single-site surgery and those of isobaric laparoscopy, and the initial experience with 14 cases. All of the procedures were performed by a single surgeon who has over 18 years of experience in laparoscopic surgery and 4 years of experience in laparoendoscopic single-site surgery. All cases of hybrid laparoscopic myomectomy were completed safely and effectively without conversion to conventional laparoscopic procedure. The median operative time was 75 minutes (range, 30 to 100 minutes). No postoperative complication was observed. The findings show that hybrid laparoscopic myomectomy is a safe and feasible surgical technique, and therefore can be a feasible, minimally invasive alternative to either abdominal or laparoendoscopic single-site surgery myomectomy.

Structural insights into photocatalytic performance of carbon nitrides for degradation of organic pollutants

Oh, Junghoon,Shim, Yeonjun,Lee, Soomin,Park, Sunghee,Jang, Dawoon,Shin, Yunseok,Ohn, Saerom,Kim, Jeongho,Park, Sungjin Elsevier 2018 Journal of solid state chemistry Vol.258 No.-

<P><B>Abstract</B></P> <P>Degradation of organic pollutants has a large environmental impact, with graphitic carbon nitride (g-C<SUB>3</SUB>N<SUB>4</SUB>) being a promising metal-free, low cost, and environment-friendly photocatalyst well suited for this purpose. Herein, we investigate the photocatalytic performance of g-C<SUB>3</SUB>N<SUB>4</SUB>–based materials and correlate it with their structural properties, using three different precursors (dicyandiamide, melamine, and urea) and two heating processes (direct heating at 550°C and sequential heating at 300 and 550°C) to produce the above photocatalysts. We further demonstrate that sequential heating produces photocatalysts with grain sizes and activities larger than those of the catalysts produced by direct heating and that the use of urea as a precursor affords photocatalysts with larger surface areas, allowing efficient rhodamine B degradation under visible light.</P> <P><B>Graphical abstract</B></P> <P>Grain size control of g-C<SUB>3</SUB>N<SUB>4</SUB> was performed using direct/sequential heating processes. Photocatalytic activities for RhB degradation was increased with larger grain size-based C<SUB>3</SUB>N<SUB>4</SUB> materials and urea driven g-C<SUB>3</SUB>N<SUB>4</SUB> produced with sequential heating has the best photocatalytic activity under visible light.</P> <P>[DISPLAY OMISSION]</P>

뉴럴 텐서 네트워크 기반 주식 개별종목 지식개체명 추출 방법에 관한 연구

양윤석(Yunseok Yang),이현준(Hyun Jun Lee),오경주(Kyong Joo Oh) 한국지능정보시스템학회 2019 지능정보연구 Vol.25 No.2

Selecting high-quality information that meets the interests and needs of users among the overflowing contents is becoming more important as the generation continues. In the flood of information, efforts to reflect the intention of the user in the search result better are being tried, rather than recognizing the information request as a simple string. Also, large IT companies such as Google and Microsoft focus on developing knowledge-based technologies including search engines which provide users with satisfaction and convenience. Especially, the finance is one of the fields expected to have the usefulness and potential of text data analysis because it’s constantly generating new information, and the earlier the information is, the more valuable it is. Automatic knowledge extraction can be effective in areas where information flow is vast, such as financial sector, and new information continues to emerge. However, there are several practical difficulties faced by automatic knowledge extraction. First, there are difficulties in making corpus from different fields with same algorithm, and it is difficult to extract good quality triple. Second, it becomes more difficult to produce labeled text data by people if the extent and scope of knowledge increases and patterns are constantly updated. Third, performance evaluation is difficult due to the characteristics of unsupervised learning. Finally, problem definition for automatic knowledge extraction is not easy because of ambiguous conceptual characteristics of knowledge. So, in order to overcome limits described above and improve the semantic performance of stock-related information searching, this study attempts to extract the knowledge entity by using neural tensor network and evaluate the performance of them. Different from other references, the purpose of this study is to extract knowledge entity which is related to individual stock items. Various but relatively simple data processing methods are applied in the presented model to solve the problems of previous researches and to enhance the effectiveness of the model. From these processes, this study has the following three significances. First, A practical and simple automatic knowledge extraction method that can be applied. Second, the possibility of performance evaluation is presented through simple problem definition. Finally, the expressiveness of the knowledge increased by generating input data on a sentence basis without complex morphological analysis. The results of the empirical analysis and objective performance evaluation method are also presented. The empirical study to confirm the usefulness of the presented model, experts’ reports about individual 30 stocks which are top 30 items based on frequency of publication from May 30, 2017 to May 21, 2018 are used. the total number of reports are 5,600, and 3,074 reports, which accounts about 55% of the total, is designated as a training set, and other 45% of reports are designated as a testing set. Before constructing the model, all reports of a training set are classified by stocks, and their entities are extracted using named entity recognition tool which is the KKMA. for each stocks, top 100 entities based on appearance frequency are selected, and become vectorized using one-hot encoding. After that, by using neural tensor network, the same number of score functions as stocks are trained. Thus, if a new entity from a testing set appears, we can try to calculate the score by putting it into every single score function, and the stock of the function with the highest score is predicted as the related item with the entity. To evaluate presented models, we confirm prediction power and determining whether the score functions are well constructed by calculating hit ratio for all reports of testing set. As a result of the empirical study, the presented model shows 69.3% hit accuracy for testing set which consists of 2,526 reports. this hit ratio is meaningfully hi

Development and validation of multiphysics PWR core simulator KANT

Taesuk Oh,Yunseok Jeong,Husam Khalefih,Yonghee Kim Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

KANT (KAIST Advanced Nuclear Tachygraphy) is a PWR core simulator recently developed at Korea Advance Institute of Science and Technology, which solves three-dimensional steady-state and transient multigroup neutron diffusion equations under Cartesian geometries alongside the incorporation of thermal-hydraulics feedback effect for multi-physics calculation. It utilizes the standard Nodal Expansion Method (NEM) accelerated with various Coarse Mesh Finite Difference (CMFD) methods for neutronics calculation. For thermal-hydraulics (TH) calculation, a single-phase flow model and a one-dimensional cylindrical fuel rod heat conduction model are employed. The time-dependent neutronics and TH calculations are numerically solved through an implicit Euler scheme, where a detailed coupling strategy is presented in this paper alongside a description of nodal equivalence, macroscopic depletion, and pin power reconstruction. For validation of the steady, transient, and depletion calculation with pin power reconstruction capacity of KANT, solutions for various benchmark problems are presented. The IAEA 3-D PWR and 4-group KOEBERG problems were considered for the steady-state reactor benchmark problem. For transient calculations, LMW (Lagenbuch, Maurer and Werner) LWR and NEACRP 3-D PWR benchmarks were solved, where the latter problem includes thermal-hydraulics feedback. For macroscopic depletion with pin power reconstruction, a small PWR problem modified with KAIST benchmark model was solved. For validation of the multi-physics analysis capability of KANT concerning large-sized PWRs, the BEAVRS Cycle1 benchmark has been considered. It was found that KANT solutions are accurate and consistent compared to other published works.

콘크리트 충전 강관을 이용한 스페이스 트러스 거더교의 설계와 시공 사례

이윤석(YunSeok Lee In),김인규(In-Gyu Kim),김영진(Young-Jin Kim),오현철(Hyun-Chul Oh),마향욱(Hyang-Wook Ma) 한국콘크리트학회 2009 콘크리트학회지 Vol.21 No.3