• Journal of Life Science
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• v.28 no.8
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• pp.992-998
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• 2018

Cancer cells grow in an environment composed of various components that supports tumor growth. Major cell types in the tumor microenvironment are fibroblast, endothelial cells and immune cells. All of these cells communicate with cancer cells. Among infiltrating immune cells as an abundant component of solid tumors, macrophages are a major component of the tumor microenvironment and orchestrates various aspects of immunity. The complex balance between pro-tumoral and anti-tumoral effects of immune cell infiltration can create a chronic inflammatory microenvironment essential for tumor growth and progression. Macrophages express different functional programs in response to microenvironmental signals, defined as M1 and M2 polarization. Tumor-associated macrophages (TAM) secret many cytokines, chemokines and proteases, which also promote tumor angiogenesis, growth, metastasis and immunosuppression. TAM have multifaceted roles in the development of many tumor types. TAM also interact with cancer stem cells. This interaction leads to tumorigenesis, metastasis, and drug resistance. TAM obtain various immunosuppressive functions to maintain the tumor microenvironment. TAM are characterized by their heterogeneity and plasticity, as they can be functionally reprogrammed to polarized phenotypes by exposure to cancer-related factors, stromal factors, infections, or even drug interventions. Because TAMs produce tumor-specific chemokines by the stimulation of stromal factors, chemokines might serve as biomarkers that reflect disease activity. The evidence has shown that cancer tissues with high infiltration of TAM are associated with poor patient prognosis and resistance to therapies. Targeting of TAM in tumors is considered a promising therapeutic strategy for anti-cancer treatment.

• Journal of the Korean earth science society
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• v.34 no.1
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• pp.59-68
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• 2013

Focal mechanism solutions in the southwestern region of the Korean Peninsula ($34^{\circ}N-36^{\circ}N$, $126^{\circ}E-128^{\circ}E$) were obtained from the analysis of the recent 22 earthquakes ($M{\geq}2.0$) occurred from January, 2005 to March, 2011. The spatial differences between the epicenters recalculated by this study and those by KMA (Korea Meteorological Administration) and KIGAM (Korea Institute of Geoscience and Mineral Resources) are less than $0.05^{\circ}$, indicating a small deviation. However, they become a little bit larger in the coastal area due to a biased arrangement of seismic stations. Redetermined depths of hypocenters show a difference less than 12.7 km by comparison with the depth data announced by KIGAM. Most epicenters in inland area are located closely to the lineaments. Fault plane solutions were obtained from the analysis of P and SH wave polarities, and SH/P amplitude ratios. They show strike-slip faulting or strike-slip faulting with reverse components dominantly. The P-axes trends are mainly ENE-WSW or E-W directions. The direction of fault plane and auxiliary plane with 'NNE-SSW and WNW-ESE' or 'NE-SW and NW-SE' are dominant and almost parallel to the general trends of lineaments in the study area.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.140-147
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• 2010

Japanese encephalitis virus (JEV), a member of the mosquito-borne flaviviruses, causes epidemics of viral encephalitis in the Southeastern Asia. JEV is a small enveloped virus with a positive-sense RNA genome; the infectious virion consists of three structural proteins, namely capsid, membrane (M; a mature form of its prM precursor), and envelope proteins. Here, we investigated a role of the charged residues found at the N-terminus of the JEV M protein in virus production. Using an infectious JEV cDNA, we generated two mutant cDNAs, Mm1 and Mm2, by charged-to-alanine substitution for $E^9$ and $K^{15}K^{16}E^{17}$ residues of the M protein, respectively. By transfection of wild-type or each of the two mutant RNAs transcribed from the corresponding cDNAs, we found that Mm2, but not Mm1, had a ~3-log decrease in virus production, even though a comparable amount of all three structural proteins were produced in transfected cells. Interestingly, the prM protein expressed in Mm2 RNA-transfected cells was not recognized by the polyclonal antiserum raised against the N-terminal 44 amino acids of the wild type M protein, but reacted to the antiserum raised against the corresponding region of the mutant Mm2. Our results indicate that three charged residues ($K^{15}K^{16}E^{17}$) in JEV M protein play a role in virus production. Two polyclonal antisera specifically recognizing the wild-type or Mm2 version of the M protein would provide a useful reagent for the functional study of this protein in the virus life cycle.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.5
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• pp.23-29
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• 2009

On December 13, 1996, an earthquake with local magnitude (M$_L$) 4.5 occurred in the Yeongwol area of South Korea. The epicenter was 37.2545$^{\circ}$N and 128.7277$^{\circ}$E, which is located inside the Okcheon Fold Belt. The waveform inversion analysis was carried out to estimate source parameters of the event according to the filtering bandwidth of seismic data. Using 0.02$\sim$0.2 Hz filtering bandwidth, focal depth and seismic moment were estimated to be 6 km and 1.3$\times$10$^{16}$ N$\cdot$m, respectively. This seismic moment corresponds to the moment magnitude (M$_W$) 4.7. The focal mechanism by the waveform inversion and P wave first motion polarity analysis is a strike slip faulting including a small thrust component, and the direction of P-axis is ENE-WSW. The moment magnitude estimated by spectral analysis was 4.8, which is similar to that estimated by waveform inversion. Average stress drop was estimated to be 14.3 MPa.

• Elastomers and Composites
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• v.34 no.3
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• pp.222-228
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• 1999

In this work, the effect of chemical treatments on the carbon blacks as-received has been studied in the context of surface, adsorption, microstructure properties, and physical surface free energetics. As an experimental result, the basic chemical treatment leads to an increase in the either dispersive or specific component without significant change the pH and specific surface area. While, acidic chemical treatment do significantly change the surface and adsorption properties, and microstructures of the carbon blacks. In particular, the result given by basic chemical treatment shows an increase of the London dispersive component of the surface free energy which is a major parameter in evaluating the dispersion or specific surface area of the carbon blacks studied. This is probably a major role in evaluating the dispersion the carbon blacks, which are reinforced in elastomer matrix in a composite system.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.3
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• pp.1-8
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• 2002

The object of this study was to determine the surface energy of hydrophobically modified micro-crystalline cellulose (MCC) with AKD and evaluate the effect of surface energy of the solid particles dispersed in aqueous medium on flotation efficiency. Especially to eliminate the complication derives from the diverse parameters of solid particles including particle size, type, etc. MCC's modified with AKD have been used. The surface energy Parameters were calculated from advancing contact angles of apolar and polar liquids on MCC pellets using the Lifshitz-van der Waals acid-base (LW:AB) approach. Total surface energy of hydrophobic MCC ranged from 46.19 mN/m to 48.60 mN/m. The contribution of the acid-base components to the total surface energy ranged form 13% to 17% for hydrophobic MCC's. The effect of surface characteristics on the flotation efficiency was evaluated. It was shown that there exist critical values of surface energies to increase flotation efficiency. Total surface energy and polar component of solid particles should be lower than 47 mN/m and 7 mN/m, respectively, for effective removal in the flotation process.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.5
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• pp.87-93
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• 2005

In order to develope high concentration$\cdot$yield ozonizer, superposed discharge type ozonizer using overlap of silent discharge and internal electrode of mesh type has been designed and manufactured. It consists of three electrodes(central electrode, internal electrode and external electrode) and double gaps(gap between central electrode and internal electrode, gap between internal electrode and external electrode). Therefore, ozone is generated by overlapping silent discharges generated between the gaps respectively for which the AC high voltages applied to the internal electrode and the external electrode has a $180{[^\circ]}$ phase difference and for which the central electrode is a ground Ozone generation characteristics proportional to mesh of internal electrode by increasing of discharge electrode and controlling of discharge power density. As a result, the in maximum ozone concentration, generation, and yield can be obtained 17,720[ppm], 5.4[g/h], and 205[g/kwh] respectively.

• Journal of Korean Medical classics
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• v.13 no.2 s.17
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• pp.44-56
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• 2000

장개빈(張介賓)(1563-1640, 호시경악(號是景岳))시명말의학가이계승김원대의학전통적인물(是明末醫學家而繼承金元代醫學傳統的人物). 타재(他在) 류경도익(類經圖翼), 의역의(醫易義) 주장'의역동원'이논증의학여역학지회통성(主張'醫易同源'而論證醫學與易學之會通性). 타이성리학이론내연구의학(他以性理學理論來硏究醫學). 인이피칭위'유의'(因而被稱爲'儒醫'). 타광범지연구유가급제자백가지후(他廣範地硏究儒家及諸子百家之後), 이(以) 황제내경(黃帝內經) 여(與) 난경 위주(難經 爲主). 종합의가학설(綜合醫家學說). 타이(他以) '양상부족음본무여'지관념내설명인체내음양상태('陽常不足陰本無餘'之觀念來說明人體內陰陽狀態) 이반박주진형지자음론(而反駁朱震亨之滋陰論). 인이주장'부양억음'급'태극시명문'적학설(因而主張'扶陽抑陰'及'太極是命門'的學說). 타재(他在) 의역의(醫易義) 이부양억음내해설병리(以扶陽抑陰來解說病理). 관어태극-명문적론의야수성리학태극개념적영향(關於太極-命門的論議也受性理學太極槪念的影響). 단시(但是), 소위(所謂) '조원찬화'('調元贊化') '기사회생'적의학목적시속어도교양생론('起死回生'的醫學目的是屬於道敎養生論). 관어차점(關於此點), 연피칭위유의적성리학의가야병부예외(連被稱爲儒醫的性理學醫家也竝不例外). 일반인위 황제내경 시재전국 한대초기형성적(一般認爲 黃帝內經 是在戰國 漢代初期形成的). 야인위기의학체계반영저황로사상여음양오행론(也認爲其醫學體系反映著黃老思想與陰陽五行論). 장개빈수재성리학적립장내주장자기적이론(張介賓雖在性理學的立場來主張自己的理論). 단시대폭지접수도가급도교립장(但是大幅地接受道家及道敎立場). 타재(他在) 류경도익(類經圖翼), 태극도론(太極圖論), 이태극성위만물생명적근원(以太極成爲萬物生命的根源). 동시언급도도가여역위(同時言及到道家與易緯). 재장개빈(在張介賓), 태극시상통어도가발생론적개념(太極是相通於道家發生論的槪念). 야상통어태극적개념(也相通於太極的槪念). 재(在) 유경(類經), 섭생(攝生) 내간(來看). 타제요로장이외(他除了老莊以外). 우인용송대이후내단사상가강백단 이도순등적주장(又引用宋代以後內丹思想家强伯端 李道純等的主張), 인이전개자기적이론(因而展開自己的理論). 필자시위(筆者視爲), 장개빈재의학적양생방면상접수료이'성명쌍수'위기적송대이후내단사상(張介賓在醫學的養生方面上接受了以'性命雙修'爲基的宋代以後內丹思想). 병차타이연단적관점내이해부양억음(竝且他以煉丹的觀點來理解扶陽抑陰). 신위유의적장개빈능구장유도량자회통위일조의학체계적의거재어역학.(身爲儒醫的張介賓能구將儒道兩者會通爲一條醫學體系的依據在於易學). 장개빈재천인상응관념지하(張介賓在天人相應觀念之下), 용이음양변화지기구내변증천인관계(用以陰陽變化之機構來辨證天人關係). 재타적이론(在他的理論), 천지시속어 역(天地是屬於 易), 인시속어 의(人是屬於 醫), 단시양자귀위동일양적일리(但是兩者歸爲同一樣的一理). 재'원취제물(在'遠取諸物), 근취제신'적관점내강(近取諸身'的觀點來講), 타장'근취제신'적도리취어의학(他將'近取諸身'的道理取於醫學). 환유'원취제물'적도리취어역학(還有'遠取諸物'的道理取於易學), 인이모구귀납성일개원리(因而謀求歸納成一個原理). 타장자연현상적원리내재어인지생명(他將自然現象的原理內在於人之生命), 종여차정체적각도내간(從如此整體的角度來看). 가이설의학시상통어역학적(可以說醫學是相通於易學的). 역학대인여자연간적탐구(易學對人與自然間的探求), 비교측중어이론성(比較側重於理論性). 반이의학이역학이론위자(反而醫學以易學理論爲資). 관어자연여인지생명진일보지진행교구체성적연구(關於自然與人之生命進一步地進行較具體性的硏究). 총지(總之), 장개빈통과태극음양론(張介賓通過太極陰陽論), 부분유 도이참재'생명'적립장(不分儒 道而站在'生命'的立場), 광범지접납유도양가(廣範地接納儒道兩家). 유차(由此) 아문가이여도장개빈의서적가치병부한어의학가치(我們可以如道張介賓醫書的價値竝不限於醫學價値). 장개빈의서제시유 도량가가이회통어"생명사상"적철학상가능성(張介賓醫書提示儒 道兩家可以會通於"生命思想"的哲學上可能性).

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.12
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• pp.80-87
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• 2013

A novel instrumentation amplifier(IA) using positive polarity current-conveyor(CCII+) for electronic measurement systems with low cost, wideband, and gain control with wide range is designed. The IA consists of two CCII+, three resistor, and an operational amplifier(op-amp). The principal of the operating is that the difference of two input voltages applied into two CCII+ used voltage and current follower converts into same currents, and then these current drive resistor of (+) terminal and feedback resistor of op-amp to obtain output voltage. To verify operating principal of the IA, we designed the CCII+ and used commercial op-amp LF356. Simulation results show that voltage follower used CCII+ has offset voltage of 0.21mV at linear range of ${\pm}$4V. The IA had wide gain range from -20dB to 60dB by variation of only one resistor and -3dB frequency for the gain of 60dB was 400kHz. The IA also has merits without matching of external resistor and controllable offset voltage using the other resistor. The power dissipation of the IA is 130mW at supply voltage of ${\pm}$5V.

• Journal of the Korean earth science society
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• v.28 no.2
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• pp.202-213
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• 2007

The Odaesan earthquake $(M_L=4.8)$ occurred near Mt. Odae, Jinbu-Myon, Pyongchang-Gun, Kangwon Province on January 20, 2007. It has a shallow focal depth about 10 km. Its felt area covers most of the southern peninsula except some southern and western inland area. The maximum MM intensity was VI in the areas including Jinbu, Doam, Kangreung, Jumunjin, and Pyongchang. In these areas, there was a very strong shaking that caused several cracks on the walls of buildings and houses, slates falling off the roof, tiles being off the wall, things falling off the desk, and rock falling from the mountains. In order to get fault plane solutions, grid searches were performed by fitting distributions of P-wave first-motion polarities and SH/P amplitude ratios for each event. The results showed that the main shock represented right-lateral strike-slip sense and two aftershocks, reverse sense. It seems that the seismogenic fault may be the NNE-SSW trending Weoljeongsa fault near the epicenter based on the distribution of epicenters (foreshock, main shock, and aftershocks), damage area, and fault plane solution. The distribution of the epicenters indicates that the length of the subsurface rupture is estimated to be about 2 km.