• Title/Summary/Keyword: GPF

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Gastropleural Fistula: A Rare Complication of Ewing Sarcoma

  • Bozkurt, Mehmet Abdussamet;Kones, Osman;Basoglu, Irfan;Alis, Halil
    • Journal of Chest Surgery
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    • v.46 no.4
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    • pp.293-294
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    • 2013
  • Gastropleural fistula (GPF) is a rare condition that can occur as a consequence of prior pulmonary surgery, trauma, or malignancy. Conservative management usually fails, and gastrectomy and even thoracotomy is often required, especially in debilitated patients. We present a patient with GPF who had a history of Ewing's sarcoma. Diagnosis of GPF was confirmed by upper gastrointestinal system endoscopy and radiographic contrast examination, and the patient underwent a laparoscopic wedge resection of the fistula. To our knowledge, this is the first report of a GPF, in the formation of which recurrence of Ewing's sarcoma had played a role and in the treatment of which wedge resection of the fistula was performed. Laparoscopic treatment of GPF may be associated with less morbidity and should be considered as the initial procedure of choice.

An Analysis of the Differences in Research-related Constructs: Serial Comparson of the Graduate Students in Global Ph. D Fellowship and Brain Korea 21 Projects (대학원생들의 연구관련 성과 변인들의 차이 분석: 글로벌 박사양성 프로젝트와 두뇌한국21사업을 중심으로)

  • Jang, Deok-Ho
    • Journal of Engineering Education Research
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    • v.16 no.3
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    • pp.20-27
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    • 2013
  • The purpose of this study is to compare the key research-related constructs, research insterest, research self-efficacy, research productivity, and research outcome expectation of the graduate students, who are participating in Global Ph.D Fellowship (GPF) and Brain Korea (BK) 21 projects. The overall results show that the mean scores of GPF students in research interest, research self-efficacy, research productivity, and research outcome expectation are higher than those of BK21. However, the higher mean scores of doctoral students in both GPF and BK21 projects imply that the longer you stay in graduate program, the better researcher you can be. Although GPF program selected higher potential students and they seem to work very hard with high expectation to be competent researchers, compatible outcome also could be possible by BK21 project.

A novel protocol for batch-separating gintonin-enriched, polysaccharide-enriched, and crude ginsenoside-containing fractions from Panax ginseng

  • Rami Lee;Han-Sung Cho;Ji-Hun Kim;Hee-Jung Cho;Sun-Hye Choi;Sung-Hee Hwang;Hyewon Rhim;Ik-Hyun Cho;Man-Hee Rhee;Do-Geun Kim;Hyoung-Chun Kim;Seung-Yeol Nah
    • Journal of Ginseng Research
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    • v.47 no.3
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    • pp.366-375
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    • 2023
  • Background: Ginseng contains three active components: ginsenosides, gintonin, and polysaccharides. After the separation of 1 of the 3 ingredient fractions, other fractions are usually discarded as waste. In this study, we developed a simple and effective method, called the ginpolin protocol, to separate gintonin-enriched fraction (GEF), ginseng polysaccharide fraction (GPF), and crude ginseng saponin fraction (cGSF). Methods: Dried ginseng (1 kg) was extracted using 70% ethanol (EtOH). The extract was water fractionated to obtain a water-insoluble precipitate (GEF). The upper layer after GEF separation was precipitated with 80% EtOH for GPF preparation, and the remaining upper layer was vacuum dried to obtain cGSF. Results: The yields of GEF, GPF, and cGSF were 14.8, 54.2, and 185.3 g, respectively, from 333 g EtOH extract. We quantified the active ingredients of 3 fractions: L-arginine, galacturonic acid, ginsenosides, glucuronic acid, lysophosphatidic acid (LPA), phosphatidic acid (PA), and polyphenols. The order of the LPA, PA, and polyphenol content was GEF > cGSF > GPF. The order of L-arginine and galacturonic acid was GPF >> GEF = cGSF. Interestingly, GEF contained a high amount of ginsenoside Rb1, whereas cGSF contained more ginsenoside Rg1. GEF and cGSF, but not GPF, induced intracellular [Ca2+]i transient with antiplatelet activity. The order of antioxidant activity was GPF > GEF = cGSF. Immunological activities (related to nitric oxide production, phagocytosis, and IL-6 and TNF-α release) were, in order, GPF > GEF = cGSF. The neuroprotective ability (against reactive oxygen species) order was GEF > cGSP > GPF. Conclusion: We developed a novel ginpolin protocol to isolate 3 fractions in batches and determined that each fraction has distinct biological effects.

Governor-Response Power Flow Based Long-term Voltage Stability Simulation (조속기 응동 조류계산 기반 장기 전압안정도 모의)

  • Song, Hwa-Chang;Kim, Young-Gon;Lee, Byong-Jun
    • Proceedings of the KIEE Conference
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    • 2008.11a
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    • pp.160-162
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    • 2008
  • This paper present a practical method for long-term voltage stability simulation based on a governor-response power flow. Governor-response power flow (GPF) is to model the long-term system response in the interval from 3 to 30 seconds after disturbance. In this paper, it is assumed that the GPF model ran capture the system state before load restoration starts in contingent conditions. This paper discusses the applicability of GPF to long-term simulation for voltage stability analysis and then explains the GPF formulation and the procedure of the proposed simulation. In addition the paper includes the simulation results with the modified New England 39-bus system.

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Effects of Radioprotectors on DNA Repair Capacity of Tumor Cells

  • Kim, Choon-Mi;Kim, Mi-Kyung
    • Archives of Pharmacal Research
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    • v.16 no.4
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    • pp.259-264
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    • 1993
  • Three cell lines, CHO, L929 and B16 which are non-tumorigenic and cancer cells, respectively, were first tested for their survival in the presence of radioprotective ginseng protein fraction(GPF0. The influence of three radioprotectors-CPF, cysteamine, and 1-Methyl-2-bis[(2-methylthio)vinyl] quinolinium iodide (MVQI) on DNA repair capacity of UV damaged cells survival test, the GPF showed higher cytotoxicity in L929 and B16 than in CHO cells. However, the degree of cell killing was also investigated by measuring $^3H$-thymidine incorporation of PUVA treated cells. In cell survival test, the GPF showed higher cytotoxicity in L929 and B16 than in CHO cells. However, the degree of cell killing was not high enough to consider it as an antitumorigenic agent. Variable results were obtained in the effects on DNA repair capacity depending on the protectors and cell lines used. In pretreatment, the presence of GPF and MVOI brought about a sinificant increase in the capacity in both CHO and B16 cells. However, in L929, the enhancing effect was not shown. In all three cell lines, cysteamine showed lower repair capacity than control, suggesting the primary damage reduction in stronger enhancing effects in L929 and B16 cells, while it was weaker in CHO cells. Here also cystemine hsowed a very little or no increase in the capacity in all three cell lines. These results demonstrate that GPF has mild cytotoxicity in tumorignic cells and that GPF and MVQI enhance DNA repair capacity of UV damaged cells, whether they are tumorigenic or not. On the other hand, cysteamine shows only damage reduction effect. Celles of different genetic origin seem to give different responses to the modifier and different modifiers may possibly work by different mechanisms.

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Aggressive Subchannel Allocation Algorithm for Optimize Transmission Efficiency Among Users in Multiuser OFDMA System (다중 사용자 OFDMA 시스템에서의 사용자간 전송효율 최적화를 위한 Aggressive Subchannel Allocation 알고리즘)

  • Ko Sang-Jun;Heo Joo;Chang Kyung-Hi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6A
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    • pp.617-626
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    • 2006
  • In this paper, we propose an ASA(Aggressive Subchannel Allocation) algorithm, which is an effective dynamic channel allocation algorithm considering all user's channel state to maximize downlink sector throughput in OFDMA system. We compare an ASA algorithm with Round Robin, ACG(Amplitude Craving Greedy), RCG(Rate Craving Greedy) and GPF(General Proportional Fair) in the 2-tier environment of FRF(Frequency Reuse Factor) 1 and then analyze the performance of each algorithms, through compute simulation. Simulation results show that the proposed ASA algorithm gets 58 %, 190 %, 130 % and 8.5 % better sector throughput compared with the Round Robin, ACG, RCG and GPF respectively.

6'-O-Galloylpaeoniflorin Protects Human Keratinocytes Against Oxidative Stress-Induced Cell Damage

  • Yao, Cheng Wen;Piao, Mei Jing;Kim, Ki Cheon;Zheng, Jian;Cha, Ji Won;Hyun, Jin Won
    • Biomolecules & Therapeutics
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    • v.21 no.5
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    • pp.349-357
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    • 2013
  • 6'-O-galloylpaeoniflorin (GPF) is a galloylated derivate of paeoniflorin and a key chemical constituent of the peony root, a perennial flowering plant that is widely used as an herbal medicine in East Asia. This study is the first investigation of the cytoprotective effects of GPF against hydrogen peroxide ($H_2O_2$)-induced cell injury and death in human HaCaT keratinocytes. GPF demonstrated a significant scavenging capacity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, $H_2O_2$-generated intracellular reactive oxygen species (ROS), the superoxide anion radical ($O_2^-$), and the hydroxyl radical (${\cdot}$OH). GPF also safeguarded HaCaT keratinocytes against $H_2O_2$-provoked apoptotic cell death and attenuated oxidative macromolecular damage to DNA, lipids, and proteins. The compound exerted its cytoprotective actions in keratinocytes at least in part by decreasing the number of DNA strand breaks, the levels of 8-isoprostane (a stable end-product of lipid peroxidation), and the formation of carbonylated protein species. Taken together, these results indicate that GPF may be developed as a cytoprotector against ROS-mediated oxidative stress.

Optimal Governor Response Power Flow with Nonlinear Interior Point Method (비선형 내점법을 이용한 최적 조속기 응동 조류계산)

  • Kim, Tae-Gyun;Lee, Byong-Joon;Song, Hwa-Chang;Cha, Jun-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.9
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    • pp.1527-1534
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    • 2007
  • This paper proposes a new concept of optimal governor-response power flow (OGPF) to obtain an optimal set of control parameters when the systems are in mid-term conditions after disturbances, ignoring the system dynamics. The idea of GOPF simply comes from the attempt to find an optimal solution of the governor-response power flow (GPF), which is a pre-exiting tool that is used to get power flow solutions that would exist several seconds after an event is applied. GPF incorporates the simplified model of governors in the systems into the power flow equations. This paper explains the concept of OGPF and depicts the OGPF formulation and application of a nonlinear interior point method as the solution technique. Also, this paper includes an example with New England 39-bus test system to illustrate the effectiveness of GOPF.

A Route Recovery Method for position based Ad hoc routing (위치기반 Ad hoc 라우팅에서 경로복구 방법론)

  • 차우석;유석대;조기환
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.04a
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    • pp.328-330
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    • 2002
  • Ad hoc 네트워크는 유선기반구조 없이 지리적으로 분산된 노드들이 동적으로 연결되어 자치적인 네트워크를 구성한다. 라우팅 프로토콜은 무선자원을 효율적으로 사용하기 위해서 최소의 오버 헤드를 갖도록 수행되어야 한다. 위치기반 라우팅 프로토콜은 위치정보를 이용하여 노드들간의 경로를 설정하고 유지할 필요 없이 직접 데이터 패킷을 전송하도록 지원하는 라우팅 프로토콜이다. 본 논문에서는 위치기반 라우팅 프로토콜인 GPF(Greedy Packet Forwarding)기법을 이용하여 패킷을 전송하는 도중 패킷을 전송할 수 없는 영역에 도착했을 때, 지역적인 flooding을 이용하여 이를 복구하는 방법론을 제시한다. 이 복구방법에서 전반적인 패킷 전송은 GPF기법을 적용하며, GPF기법을 적용할 수 없는 영역에서만 지역적으로 flooding 알고리즘을 적용한다. 따라서 제어메시지를 지역에 국한시켜 사용함으로써 제한된 무선자원을 효율적으로 사용할 수 있다. 또한 노드들의 수가 증가하는 네트워크 환경에서 보다나은 확장성을 기대할 수 있다.

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