Clinical Outcomes of a Preoperative Inferior Vena Cava Filter in Acute Venous Thromboembolism Patients Undergoing Abdominal-Pelvic Cancer or Orthopedic Surgery

Youngjin HAN 대한외과학회 2018 대한외과학회 학술대회 초록집 Vol.2018 No.11

Immediate Breast Reconstruction vs. Mastectomy Alone in Locally Advanced Breast Cancer; Local Recurrence and Distant Recurrence

Youngjin Kim,Eun-Shin Lee,Jong Ho Cheun,Jigwang Jung,Han-Byoel Lee,Hyeong-Gon Moon,Dong-Young Noh,Wonshik Han 한국유방암학회 2019 Journal of Breast Disease Vol.7 No.2

Purpose: The oncologic safety of immediate breast reconstruction (IBR) has been demonstrated. However, the outcome of IBR for locally advanced breast cancer (LABC) is still under debate. We compared the survival outcome of LABC patients who underwent IBR vs. mastectomy alone. Methods: We retrospectively analyzed a total of 248 patients with stage III breast cancer who were treated with mastectomy between 2004 and 2015. The study subjects were divided into 2 groups: patients who received IBR (n=77) or mastectomy alone (MA) (n=171). We compared disease-free survival (DFS) of both groups. Results: Median follow-up duration was 49 months and the mean age of patients was 49 years. Patients in the IBR group were significantly younger and had lower body mass index (BMI) than those in the MA group. In a univariate analysis, IBR group showed better DFS than the MA group (DFS 81.3 months vs. 49.8 months, p<0.001). There was no delay in adjuvant treatment in the IBR group. In a multivariate analysis, IBR was associated with better DFS (hazard ratio (HR) for recurrence: 0.37, 95% CI 0.20–0.69, p=0.002) when adjusted for potential prognostic factors. In a subgroup analysis performed according to disease stage (IIIA and IIIB/IIIC), DFS was significantly better in IBR than MA group in both stage subgroups (p<0.001). Conclusion: We demonstrated that patients who underwent IBR showed better DFS outcome compared with patients who underwent mastectomy alone. Our results can help surgeons to determine if IBR is an option in patients with LABC.

Clinical outcome of early relaparotomy after elective open repair of abdominal aortic aneurysms

Youngjin Han,Tae-Won Kwon,Gi-Young Ko,Hojong Park,Ji Yoon Choi,Yong-Pil Cho 대한외과학회 2015 Annals of Surgical Treatment and Research(ASRT) Vol.88 No.3

Purpose: The aim of this study was to retrospectively evaluate the association of need for early relaparotomy with clinical outcomes after elective open repair of abdominal aortic aneurysms (AAAs). Methods: A total of 292 consecutive patients who underwent elective open AAA repair at Asan Medical Center from January 2001 to December 2010 were included in this study, and we compared the demographics, clinical characteristics, related risk factors, and clinical outcomes of early relaparotomy versus nonrelaparotomy patients. Results: The incidence of early relaparotomy during a single hospital stay was 4.1% (n = 12), and the most common causes were bowel ischemia (n = 5, 41.7%) and postoperative bleeding (n = 3, 25.0%). Among the demographics and clinical characteristics significantly associated with relaparotomy were: age (P = 0.025), chronic obstructive pulmonary disease (COPD) (P = 0.010), number of RBC units transfused during the AAA repair (P = 0.022) and in the following week (P = 0.005), and length of intensive care (P < 0.001) and overall hospital stay (P < 0.001). On multivariate analysis, presence of COPD (P = 0.009) and number of RBC units transfused during the AAA repair (P = 0.006) were statistically significantly associated with relaparotomy. Furthermore, early relaparotomy was associated with perioperative (within 30 days) (P = 0.048) and overall in-hospital mortality (P = 0.001). Conclusion: Early relaparotomy has an adverse effect on clinical outcomes: increased mortality and hospital length of stay. Presence of COPD and need for RBC transfusion are associated with early relaparotomy.

Effects of upper-extremity vascular access creation on cardiac events in patients undergoing coronary artery bypass grafting

Youngjin HAN,Yong-Pil CHO 대한외과학회 2017 대한외과학회 학술대회 초록집 Vol.2017 No.11

공간구문론을 의한 전시공간 가시성에 관한 연구 -오문 전시장 특전을 중심으로-

한한 ( Han Han ),김영진 ( Kim Youngjin ),김주연 ( Kim Jooyun ) 한국공간디자인학회 2023 한국공간디자인학회논문집 Vol.18 No.8

(Background and Purpose) In today's society, with traditional architecture vanishing, China is actively studying the modernization of these cultural treasures. Preserving valuable historical heritage not only entails protection but also leveraging its value to serve contemporary society better. The Omun exhibition hall, the entrance to the Beijing Palace known as Jeongmunseongmunru, has been modernized and is currently hosting significant exhibitions at the Palace Museum. Using spatial syntax, this study aims to intuitively optimize the modern utilization of traditional architecture, enhancing the planning and design process. The primary objective is to analyze the visibility and visitor movement patterns within the five-door exhibitions through spatial syntax. Based on this analysis, optimization proposals for exhibition space planning will be presented, ultimately elevating the overall exhibition experience. (Method) The abstract aims to study the visualization analysis principles and methods, understand the spatial form of the five-mun exhibition hall, and analyze four exhibition space layouts and planning schemes. Utilizing Depthmap Ⅹ, the connectivity, visual integration, and agent analysis of spatial visibility are calculated. Through the analysis of these values, the four exhibitions are evaluated, and optimization plans for the Omun exhibition hall are proposed. The scope of the study focuses on a special exhibition held at the Omun Exhibition Hall in Beijing in 2019, examining the arrangement and structure of the exhibition space, as well as analyzing the gaze flow and visual experiences of visitors. By comprehensively evaluating these factors, the study is completed. (Results) Through an analysis of exhibition space visibility for four special exhibitions held at Omun Exhibition Hall in 2019, this study found that three out of four exhibitions achieved good spatial connectivity, and two out of four exhibitions achieved good visual integration. Moreover, by simulating visitor activity behavior using intelligent calculations, a clear pattern of visitor flow was revealed for all four exhibitions, with a notable concentration in areas of high activity. In the future exhibition space, it was found that the exhibition space should be constructed to enhance the spatial activity of the exhibition area and improve the utilization and exposure rate of the exhibits in three key aspects: gaze map, spatial layout, multi-level exhibition, and interactive participation. (Conclusions) This study applies spatial syntax, as a modern spatial analysis theory, to traditional architectural space forms, presenting a novel research approach for investigating the modern use of traditional spaces in related fields. Therefore, it is believed that the use of spatial syntax data operations will provide a foundation for space optimization for the modern utilization of traditional architecture to fully manifest cultural and economic value.

Two-Dimensional Phosphorene-Derived Protective Layers on a Lithium Metal Anode for Lithium-Oxygen Batteries

Kim, Youngjin,Koo, Dongho,Ha, Seongmin,Jung, Sung Chul,Yim, Taeeun,Kim, Hanseul,Oh, Seung Kyo,Kim, Dong-Min,Choi, Aram,Kang, Yongku,Ryu, Kyoung Han,Jang, Minchul,Han, Young-Kyu,Oh, Seung M.,Lee, Kyu T American Chemical Society 2018 ACS NANO Vol.12 No.5

<P>Lithium-oxygen (Li-O<SUB>2</SUB>) batteries are desirable for electric vehicles because of their high energy density. Li dendrite growth and severe electrolyte decomposition on Li metal are, however, challenging issues for the practical application of these batteries. In this connection, an electrochemically active two-dimensional phosphorene-derived lithium phosphide is introduced as a Li metal protective layer, where the nanosized protective layer on Li metal suppresses electrolyte decomposition and Li dendrite growth. This suppression is attributed to thermodynamic properties of the electrochemically active lithium phosphide protective layer. The electrolyte decomposition is suppressed on the protective layer because the redox potential of lithium phosphide layer is higher than that of electrolyte decomposition. Li plating is thermodynamically unfavorable on lithium phosphide layers, which hinders Li dendrite growth during cycling. As a result, the nanosized lithium phosphide protective layer improves the cycle performance of Li symmetric cells and Li-O<SUB>2</SUB> batteries with various electrolytes including lithium bis(trifluoromethanesulfonyl)imide in <I>N,N</I>-dimethylacetamide. A variety of <I>ex situ</I> analyses and theoretical calculations support these behaviors of the phosphorene-derived lithium phosphide protective layer.</P> [FIG OMISSION]</BR>

절차적 지식과 서술적 지식의 연결을 활용한 전문가 의사 결정 지원 시스템

한지수(Jisu Han),한기준(Keejun Han),박영진(Youngjin Park),김현수(Hyunsu Kim),김무진(Mujin Kim),이문용(Mun Y. Yi) 한국정보과학회 2018 한국정보과학회 학술발표논문집 Vol.2018 No.12

Molecular characterization of the N-terminal domains of the human mitochondrial calcium uniporter (MCU) and its paralog, MCUb

Youngjin Lee,Ji Hun Kim,Bora Lee,Jung Youn Kang,Jia Jia Lim,Hyung-Seop Youn,Jung-Gyu Lee,Jun Yop An,Kyoung Ryoung Park,Tae Gyun Kim,Do Han Kim,Soo Hyun Eom 한국구조생물학회 2015 Biodesign Vol.3 No.4

Mitochondrial calcium (Ca2+) homeostasis is essential for cell survival and death. The mitochondrial calcium uniporter(MCU) homo-tetramer is a selective Ca2+ channel responsible for mitochondrial Ca2+ uptake. Its paralog, MCUb, can form a Ca2+-impermeable hetero-tetramer with MCU exerting a dominant-negative function. We report the structural modeling for MCUb N-terminal domain (NTD), which showed 83% sequence homology with MCU NTD. The MCUb NTD model structure forms a stable globular domain via a hydrophobic interior and contains conserved putative phosphorylation and ubiquitination sites. The MCUb NTD structure is similar to that of MCU NTD with a root mean square deviation (RMSD) of 0.3 Å for 96 Cα atoms. The MCUb NTD forms a stable heterodimer with MCU NTD mainly by electrostatic interaction, although both NTDs are stable as monomers. Besides, our cross-linking results reveal that both NTDs form high-order oligomers. Our findings suggest that stable heterodimer formation of MCU-MCUb NTDs affects MCU NTD clustering, resulting in inefficient clustering of MCU for efficient Ca2+ permeation at the high [Ca2+] microdomain.

Synthesis of Predictive Equivalent Consumption Minimization Strategy for Hybrid Electric Vehicles Based on Closed-Form Solution of Optimal Equivalence Factor

Han, Jihun,Kum, Dongsuk,Park, Youngjin IEEE 2017 IEEE Transactions on Vehicular Technology VT Vol.66 No.7

<P>Previously, an equivalent consumption minimization strategy (ECMS) was developed that provides near-optimal performance of hybrid vehicles based on an adaptation of equivalence factor from state of charge feedback. However, under real-world driving conditions with uncertainties, such as hilly roads, ECMS requires a predictive scheme utilizing future driving information in order to prevent a loss of optimality. In this paper, we synthesize predictive ECMS in a feedforward way to adjust the equivalence factor based on its theoretical connection with future driving statistics, in a systematic manner. First, a useful noncausal adaptation strategy is extracted from dynamic programming results. Then, the inverse problem is formulated and solved to derive an explicit representation of the constant optimal equivalence factor with justified assumptions. Finally, a causal, predictive adaptation strategy using this closed-form solution is synthesized to mimic the noncausal one, and its effectiveness is evaluated for fuel cell hybrid electric vehicles. Results show that if the predicted statistical information reflects well the future driving conditions, the proposed strategy accurately estimates the constant optimal equivalence factor, including the jump behavior, thereby yielding less than 1.5% loss of fuel optimality. Moreover, this approach is extendible to other configurations.</P>

Feasibility study of cone-beam computed tomography (CBCT) reconstruction algorithm for proton image-guided radiation therapy (IGRT)

Han, Dong-Kyoon,Jo, Byungdu,Lee, Min-Hee,Yoo, Myung Seok,Kim, Kyuseok,Lee, Youngjin Elsevier 2016 OPTIK -STUTTGART- Vol.127 No.20

<P><B>Abstract</B></P> <P>The radiation therapy is most important treatment technique in the field of the oncology. With the improved radiation therapy technologies such as proton image-guided radiation therapy (IGRT), the accuracy of the patient alignment system has been emphasized. The purpose of this study was to validate the possibility of cone-beam computed tomography (CBCT) reconstruction algorithm using X-ray and 3-D proton IGRT by acquiring images sequentially with continuous 360° gantry rotation. To confirm the feasibility of CBCT reconstruction algorithm, we acquired the reconstruction images of the proton IGRT for a mouse and ball phantom, respectively. According to the results, we demonstrated the feasibility of reconstruction algorithm for the proton IGRT. In conclusion, this reconstruction algorithm can help the determination of a treatment target and will be used a main patient alignment system for the proton IGRT. In the future work we need to compare the 180 projection view using X-ray imaging system of the proton therapy with other efficient projection views.</P>