• Title/Summary/Keyword: Lewis Number

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A Case of Bronchiolitis Obliterans Organizing Pneumonia After Thoracotomy (개흉술후 발생한 Bronchiolitis Obliterans Organizing Pneumonia 체험 1례)

  • 원경준;박종호;백희종;이향림;조재일
    • Journal of Chest Surgery
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    • v.30 no.10
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    • pp.1040-1043
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    • 1997
  • We report a patient who suffered from bronchiolitis obliterans organizing pneumonia(BOOP) after Ivor Lewis operation for esophageal cancer. The patient presented low grade fever, dry cough and mild dyspnea at day after operation. Chest roentgenograms and chest CT revealed bilateral patchy and infiltrative shadows. The respiratory symptoms worsened and respiratory failure developed with mild elevation of WBC count despite of conservative treatment. An open lung biopsy was done and the biopsy specimen showed bronchiolitis obliterans organizing pneumonia(BOOP). After several weeks of steroid therapy, there were marked clinical, physiological and roentgenographic improvements. Our experience suggests that BOOP may be one of the underlying pathology in a number of patients presenting with ARDS after thoracotomy. Since steroid therapy may improve survival in these patients, thoracic surgeons should heighten their index of suspicion for this entity. Early histologic diagnosis should be considered in patients with treatment-resistant ARDS after thoracotomy.

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Effect of Chemical Interaction on Flame Extinction in Interacting H2-air and CO-air Premixed Flames (H2-공기와 CO-공기의 예혼합화염의 화염소화에 있어서 화학적 상호작용의 효과)

  • Jung, Seongwook;Park, Jeong;Kwon, Ohboong;Keel, Sangin;Yun, Jinhan
    • Journal of the Korean Society of Combustion
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    • v.18 no.4
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    • pp.44-52
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    • 2013
  • Important role of chemical interaction in flame extinction was numerically investigated in downstream interaction among lean(rich) and lean(rich) premixed as well as partially premixed $H_2$-air and CO-air flames. The strain rate varied from 30 to $5917s^{-1}$ until interacting flame could not be sustained anymore. Flame stability diagrams mapping lower and upper limit fuel concentrations for flame extinction as a function of strain rate are presented. Highly stretched interacting flames were survived only within two islands in the flame stability map where partially premixed mixture consisted of rich $H_2$-air flame, extremely lean CO-air flame, and a diffusion flame. Further increase in strain rate finally converges to two points. Appreciable amount of hydrogen in the side of lean $H_2$-air flame also oxidized the CO penetrated from CO-air flame, and this reduced flame speed of the $H_2$-air flame, leading to flame extinction. At extremely high strain rates, interacting flames were survived only by a partially premixed flame such that it consisted of a very rich $H_2$-air flame, an extremely lean CO-air flame, and a diffusion flame. In such a situation, both the weaker $H_2$-air and CO-air flames were parasite on the stronger diffusion flame such that it could lead to flame extinction in the situation of weakening the stronger diffusion flame. Particular concerns are focused on important role of chemical interaction in flame extinction was also discussed in detail.

Effects of CO2 Addition in Downstream Interaction between 2-Air and CO-Air Premixed Flames (H2-공기와 CO-공기 예혼합화염 사이의 후류상호작용에 있어서 CO2 첨가 효과)

  • Keel, Sang In;Park, Jeong
    • Journal of the Korean Society of Combustion
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    • v.18 no.4
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    • pp.29-36
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    • 2013
  • Numerical study was conducted to clarify effects of added $CO_2$ for the downstream interaction between $H_2$-air and CO-air premixed flames in counterflow configuration. The reaction mechanism adopted was Davis model which had been known to be well in agreement with reliable experimental data. The results showed that both lean and rich flammable limits were reduced. The most discernible difference between the two with and without having $CO_2$ addition into $H_2$-air and CO-air premixtures was two flammable islands for the former and one island for the latter at high strain flame conditions. Even a small amount of $H_2$, in which $H_2$-air premixed flame cannot be sustained by itself, participates in CO oxidation, thereby altering the CO-oxidation reaction path from the main reaction route $CO+O_2{\rightarrow}CO_2+O$ with a very long chemical time in CO-air flame to the (H, O, OH)-related reaction routes including $CO+OH{\rightarrow}CO_2+H$ with relatively short chemical times. This intrinsic nature alters flame stability maps appreciably. The results also showed that chemical effects of added $CO_2$ suppressed flame stabilization. Particularly this phenomenon was appreciable at flame conditions which lean and rich extinction boundary was merged. The detailed discussion of chemical effects of added $CO_2$ was addressed to the present downstream interaction.

Study on Flame Oscillations in Laminar Lift-off Butane Flames Diluted with Nitrogen (질소 희석된 부탄 부상화염에 있어서 화염진동에 관한 연구)

  • Yoon, Sung-Hwan;Park, Jeong;Kwon, Oh-Boong;Kim, Jeong-Soo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.7
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    • pp.729-738
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    • 2010
  • The characteristics of lifted butane flames diluted with nitrogen have been investigated experimentally in order to elucidate the mechanism of individual flame oscillation modes. Flame oscillations in laminar free-jet lift-off flames are classified into the following five regimes: a stabilized lift-off regime (I), a heat-loss-induced oscillation (II), a buoyancy-induced oscillation along with a heat-loss-induced oscillation (III), a combined form of an oscillation prior to blow-out and a heat-loss-induced oscillation (IV), and a combination of an oscillation prior to blow-out and a buoyancy-induced oscillation along with a heat-loss-induced oscillation (V). The characterization of the individual flame oscillations modes are presented and discussed using Strouhal numbers and their relevant parameters by the analysis of the power spectrum for temporal variation of the lift-off height.

Assessing the EORTC QLQ-BM22 Module Using Rasch Modeling and Confirmatory Factor Analysis across Countries: a Comprehensive Psychometric Evaluation in Patients with Bone Metastases

  • Lin, Chung-Ying;Pakpour, Amir H
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1405-1410
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    • 2016
  • Background: The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Bone Metastases Module (EORTC QLQ-BM22) is a recently designed supplement to EORTC Quality of Life Questionnaire-C30 (EORTC QLQ-C30). Additional psychometric properties, especially using confirmatory factor analysis (CFA) and the Rasch model, are warranted. Materials and Methods: A total of 573 patients with bone metastases were enrolled from eight countries with a mean${\pm}$SD age of $55.8{\pm}13.7years$. Slightly more than two thirds of them were female (n=383; 66.8%). CFA was used to examine the BM22 framework; Rasch models were applied to understand misfit items and differential item functioning (DIF). Results: The fit indices were satisfactory in CFA (comparative fit index=0.972, Tucker-Lewis index=0.964, root mean square error of approximation=0.076, and standardized root mean square residual=0.045). All items fit well in the Rasch models (mean square values were between 0.5 and 1.5), and only one item (number 17) displayed DIF across gender. However, there were six DIF items across Canada and Taiwan, ten across Canada and Iran, and six across Taiwan and Iran. Conclusions: The BM22 has satisfactory psychometric properties, and could assess the QoL of patients with bone metastases specifically focusing on their symptoms. Clinicians may want to use it to capture the underlying QoL for patients with bone metastases. However, the score of item 17 should be interpreted with caution when comparing male and female patients. In addition, researchers should note that variation in DIF items may occur when conducting an international study.

Evaluation of the Applicability of the Poisson Cluster Rainfall Generation Model for Modeling Extreme Hydrological Events (극한수문사상의 모의를 위한 포아송 클러스터 강우생성모형의 적용성 평가)

  • Kim, Dong-Kyun;Kwon, Hyun-Han;Hwang, Seok Hwan;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.3
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    • pp.773-784
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    • 2014
  • This study evaluated the applicability of the Modified Bartlett-Lewis Rectangular Pulse (MBLRP) rainfall generation model for modeling extreme rainfalls and floods in Korean Peninsula. Firstly, using the ISPSO (Isolated Species Particle Swarm Optimization) method, the parameters of the MBLRP model were estimated at the 61 ASOS (Automatic Surface Observation System) rain gauges located across Korean Peninsula. Then, the synthetic rainfall time series with the length of 100 years were generated using the MBLRP model for each of the rain gauges. Finally, design rainfalls and design floods with various recurrence intervals were estimated based on the generated synthetic rainfall time series, which were compared to the values based on the observed rainfall time series. The results of the comparison indicate that the design rainfalls based on the synthetic rainfall time series were smaller than the ones based on the observation by 20% to 42%. The amount of underestimation increased with the increase of return period. In case of the design floods, the degree of underestimation was 31% to 50%, which increases along with the return period of flood and the curve number of basin.

Effects of H2O Addition in Downstream Interaction between H2-Air and CO-Air Premixed Flames (H2-공기와 CO-공기 예혼합 화염 사이의 후류상호작용에 있어서 H2O 첨가 효과)

  • Park, Jeong;Kwon, Oh Boong;Kim, Tae Hyung;Park, Jong Ho
    • Journal of the Korean Society of Combustion
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    • v.20 no.1
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    • pp.6-14
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    • 2015
  • Numerical study was conducted to clarify effects of added $H_2O$ for the downstream interaction between $H_2$-air and CO-air premixed flames in counterflow configuration. The reaction mechanism adopted was Davis model which had been known to be well in agreement with reliable experimental data. The results showed that both lean and rich flammable limits were reduced in increase of strain rate. The most discernible difference between the two with and without having $H_2O$ and/or $H_2$ addition into $H_2$-air and CO-air premixtures was two flammable islands for the former and one island for the latter at high strain flame conditions. Even a small amount of $H_2$, in which $H_2$-air premixed flame cannot be sustained by itself, participates in CO oxidation, thereby altering the CO-oxidation reaction path from the main reaction route $CO+O_2{\rightarrow}CO_2+O$ with a very long chemical time in CO-air flame to the OH-related reaction routes including $CO+OH{\rightarrow}CO_2+H$ with very short chemical times. This intrinsic nature alters flame stability maps appreciably. The results also showed that chemical effects of added $H_2O$ help lean flames at relatively low strain rate be sustained, and suppress the flame stabilization at high strain rates.

A Study on the Control of Microstructures of Polyalphaolefins via Cationic Polymerization (양이온 중합을 이용한 폴리알파올레핀의 미세구조 조절에 관한 연구)

  • Ko, Young Soo;Kwon, Wan-Seop;No, Myoung-Han;Yim, Jin-Heong
    • Polymer(Korea)
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    • v.39 no.2
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    • pp.346-352
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    • 2015
  • Polyalphaolefin (PAO) is a synthetic lubricant that is superior to mineral-based lubricants in the terms of physical and chemical characteristics such as low pour point, high viscosity index (VI), and thermal and oxidation stability. Several kinds of PAOs have been synthesized by using 1-pentene, 1-hexene, 1-octene, or 1-dodecene as monomer with three kinds of aluminum-based Lewis acid catalysts via cationic polymerization. The control of the catalytic performance and physical properties of PAO such like molecular weight, kinematic viscosity, pour point, and viscosity index was done by changing polymerization parameters. The alkyl aluminum halide-based catalysts show better catalytic activity than that of the conventional $AlCl_3$ catalyst. The microstructure of PAO was investigated by means of TOF-MS (time of flightmass spectroscopy) analysis in order to elucidate the correlation between the performances of the lubricant (VI, pour point) and the molecular structure of PAO. The VI of PAO increases with increases in the carbon number of ${\alpha}$-olefin. In other words, the performances of PAO as a lubricant strongly depended on the branch length of PAO.

Immunological Studies on the Antitumor Componets of the Basidiocarps of Agrocybe cylindracea

  • Kim, Byong-Kak;Hyun, Jin-won;Yoon, Jong-Myung;Choi, Eung-Chil
    • Archives of Pharmacal Research
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    • v.20 no.2
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    • pp.128-137
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    • 1997
  • The effects of cylindan, a polysaccharide isolated from the basidiocarps of Agrocybe cylindracea, on murine sarcoma 180 tumor and murine immune cells were examined after intraperitoneal administration. Cylindan exhibited a marked life extension effect in mice against ascite forms of sarcoma 180 and Lewis lung carcinoma at a dose of 50 mg/kg/day, although it did not show any direct cytotoxicity against sarcoma 180, X5563, and MM46 murine tumor cells. Cylindan increased numbers of bone marrow stem cells as well as peritoneal exudate cells in flow cytometry using monoclonal antibodies. The tumor bearing mice group apparently showed the increase of macrophages and cytotoxic T lymphocytes in mouse spleen cells during the early stage of tumor growth. But during the later stage, the control group decreased immune cells and cylindan restored the decreased immune cells in the tumor bearing mice to the normal level. In non-specific immune response, cylindan stimulated the bacterial phagocytosis and acid phosphatase production in macrophages. It also activated components of the alternative complement pathway and natural killer activity against YAC-1 lymphoma. In number of plasma cells as token of stimulation of the differentiation of B lymphocytes. In cellular immunity, cylindan restored the depressed response of delayed type hypersensitivity in the tumor bearing mice to 60% of the normal level and increased the interleukin-2 (IL-2) responsiveness in the IL-2 dependent CTLL-2 cells. These results suggest that cylindan did not show direct cytotoxic effects on tumor cells but restored the decreased immune response of the tumor bearing mice.

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Prognostic role of EGR1 in breast cancer: a systematic review

  • Saha, Subbroto Kumar;Islam, S.M. Riazul;Saha, Tripti;Nishat, Afsana;Biswas, Polash Kumar;Gil, Minchan;Nkenyereye, Lewis;El-Sappagh, Shaker;Islam, Md. Saiful;Cho, Ssang-Goo
    • BMB Reports
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    • v.54 no.10
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    • pp.497-504
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    • 2021
  • EGR1 (early growth response 1) is dysregulated in many cancers and exhibits both tumor suppressor and promoter activities, making it an appealing target for cancer therapy. Here, we used a systematic multi-omics analysis to review the expression of EGR1 and its role in regulating clinical outcomes in breast cancer (BC). EGR1 expression, its promoter methylation, and protein expression pattern were assessed using various publicly available tools. COSMIC-based somatic mutations and cBioPortal-based copy number alterations were analyzed, and the prognostic roles of EGR1 in BC were determined using Prognoscan and Kaplan-Meier Plotter. We also used bc-GenEx-Miner to investigate the EGR1 co-expression profile. EGR1 was more often downregulated in BC tissues than in normal breast tissue, and its knockdown was positively correlated with poor survival. Low EGR1 expression levels were also associated with increased risk of ER+, PR+, and HER2- BCs. High positive correlations were observed among EGR1, DUSP1, FOS, FOSB, CYR61, and JUN mRNA expression in BC tissue. This systematic review suggested that EGR1 expression may serve as a prognostic marker for BC patients and that clinicopathological parameters influence its prognostic utility. In addition to EGR1, DUSP1, FOS, FOSB, CYR61, and JUN can jointly be considered prognostic indicators for BC.