초전도 세라믹 Y-Ba-Cu-O계의 구조적 상전이와 분해거동에 관한 연구

이민호,이민상,김양수,진영철 ( M . H . Lee,M . S . Lee,Y . S . Kim,Y . C . Jin ) 한국열처리공학회 1991 熱處理工學會誌 Vol.4 No.3

In this study, the structural phase transition and decomposition of superconducting ceramic, Y-Ba-Cu-O system was studied. The results of the study are as follows. The high Tc superconductor Y₂Ba₂Cu₃O_(7-x) is made in solid state reaction of O₂atmosphere and the valve of X in Y₂Ba₂Cu₃O_(7-x) is 0.1∼0.2. The transition temperature of tetragonal-orthorhombic phase of Y₂Ba₂Cu₃O_(7-x) appear at 790℃-900℃. In the result of measuring the electrical resistance of sample annealed in O₂atmosphere, the electrical resistance show zero at 92K and the best superconductor, Y₂Ba₂Cu₃O_(7-x)(Y123) can be mabe.

Long-range transport of giant particles in Asian dust identified by physical, mineralogical, and meteorological analysis

Jeong, G. Y.,Kim, J. Y.,Seo, J.,Kim, G. M.,Jin, H. C.,Chun, Y. Copernicus GmbH 2014 Atmospheric chemistry and physics Vol.14 No.1

<P>Abstract. Giant particles transported over long distances are generally of limited concern in atmospheric studies due to their low number concentrations in mineral dust and possible local origin. However, they can play an important role in regional circulation of earth materials due to their enormous volume concentration. Asian dust laden with giant particles was observed in Korea on 31 March 2012, after a migration of about 2000 km across the Yellow Sea from the Gobi Desert. Scanning electron microscopy (SEM) revealed that 20% of the particles exceeded 10 μm in equivalent sphere diameter, with a maximum of 60 μm. The median diameter from the number distribution was 5.7 μm, which was larger than the diameters recorded of 2.5 and 2.9 μm in Asian dust storms in 2010 and 2011, respectively, and was consistent with independent optical particle counter data. Giant particles (>10 μm) contributed about 89% of the volume of the dust in the 2012 storm. Illite-smectite series clay minerals were the major mineral group followed by quartz, plagioclase, K-feldspar, and calcite. The total phyllosilicate content was ~52%. The direct long-range transport of giant particles was confirmed by calcite nanofibers closely associated with clays in a submicron scale identified by high-resolution SEM and transmission electron microscopy. Since giant particles consisted of clay agglomerates and clay-coated quartz, feldspars, and micas, the mineral composition varied little throughout the fine (<5 μm), coarse (5-10 μm), giant-S (10-20 μm), and giant-L (>20 μm) size bins. Analysis of the synoptic conditions of the 2012 dust event and its migration indicated that the mid-tropospheric strong wind belt directly stretching to Korea induced rapid transport of the dust, delivering giant particles. Giant dust particles with high settling velocity would be the major input into the terrestrial and marine sedimentary and ecological systems of East Asia and the western Pacific. Analysis of ancient aeolian deposits in Korea suggested the common deposition of giant particles from Asian dust through the late Quaternary Period. The roles of giant particles should be reviewed with regard to regional circulation of mineral particles and nutrients. </P>

세관 양광주 방전에서 플라즈마 확산의 완전 해

김동준,정종문,김정현,황하청,정재윤,조윤희,임현교,구제환,최은하,조광섭,Jin, D.J.,Jeong, J.M.,Kim, J.H.,Hwang, H.C.,Chung, J.Y.,Cho, Y.H.,Lim, H.K.,Koo, J.H.,Choi, E.H.,Cho, G.S. 한국진공학회 2010 Applied Science and Convergence Technology Vol.19 No.1

관경이 수 mm인 세관 램프 내부에서 플라즈마의 확산을 조사하기 위하여 이극성(ambipolar) 확산방정식을 해하였다. 반경 방향의 확산에 의한 유리관 벽에서의 플라즈마 소멸 특성시간은 $\tau_r\;=\;(r_0/2.4)^2/D_a$로 주어진다. 반경 $r_0{\sim}1\;mm$이고 이극성 확산계수 $D_a{\sim}0.01\;m^2/s$ 이면, $\tau_r{\sim}17\;{\mu}s$이다. 이는 램프의 교류전원 구동에서 플라즈마를 유지하기 위한 구동 최소 주파수 ~30 kHz에 해당한다. 고전압이 인가되는 전극부에 발생한 고밀도의 플라즈마가 양광주로 확산되는 특성시간은 $\tau_z{\sim}0.1\;s$이다. 고밀도 플라즈마 경계에서의 시간에 대한 확산속도는 $t{\sim}10^{-6}\;s$일 때 $u_D{\sim}10^2\;m/s$이고, $t{\sim}10^{-3}\;s$이면 그 속도는 $u_D{\sim}1\;m/s$로 느려진다. 따라서 램프 길이 ~1 m에 대하여 전극부에서 생성된 고밀도 플라즈마가 양광주 전체로 확산되는 시간은 수 초가 걸린다. The ambipolar diffusion equation has been solved in a fine-tube lamp of a few mm in diameter. In the diffusion of radial direction, the plasma diffuses and vanishes away at the glass wall by recombination with the characteristic time of plasma loss is given by $\tau_r\;=\;(r_0/2.4)^2/D_a$. With the radius $r_0{\sim}1\;mm$ and the ambipolar diffusion coefficient $D_a{\sim}0.01\;m^2/s$, the vanishing time is calculated $\tau_r{\sim}10\;{\mu}s$ which corresponds to the least value of frequency 30 kHz for the sustaining the plasma in the operation of high voltage AC-power. In the diffusion of longitudinal z-direction, a high density plasma generated at the area of a high voltage electrode, diffuses into the positive column with the characteristic time $\tau_z{\sim}0.1\;s$. The plasma diffusion velocity at the boundary of high density plasma is $u_D{\sim}10^2\;m/s$ at the time $t{\sim}10^{-6}$ s and the diffusion velocity becomes slow as $u_D{\sim}1\;m/s$ at $t{\sim}10^{-3}\;s$. Therefore, for the long lamp of 1 m, it takes about several seconds for the high density plasma at the area of electrode to diffuse through the whole positive column space.

Haplotypes for 12 Y-chromosomal STR loci in a Korean population (the central region)

Hwang, J.H.,Lee, H.,Lee, Y.A.,Han, M.S.,Kim, W.,Jin, I.,Cho, N.S. Elsevier Sequoia 2007 Forensic science international Vol.168 No.1

Haplotypes and allele frequencies of 12 STR loci included in the PowerPlex<SUP>(</SUP>R) Y system (DYS391, DYS389I, DYS439, DYS389II, DYS438, DYS437, DYS19, DYS392, DYS393, DYS390, and DYS385a/b) were obtained from a sample of 569 unrelated individuals living in the central region of Korea. A total of 473 haplotypes were observed in the 569 individuals studied, of which 426 (90.06%) were unique. The overall haplotype diversity for the 12 Y-STR loci was 0.9985, and the discrimination capacity was 0.8313. In DYS439, we found a new intermediate-sized allele that added an A at base 3 upstream from the repeat region's first GATA motif. The allele was named 11 (U3Ains) according to its sequence structure.

Upregulation of CXCR4 is functionally crucial for maintenance of stemness in drug-resistant non-small cell lung cancer cells

Jung, M-J,Rho, J-K,Kim, Y-M,Jung, J E,Jin, Y B,Ko, Y-G,Lee, J-S,Lee, S-J,Lee, J C,Park, M-J Macmillan Publishers Limited 2013 Oncogene Vol.32 No.2

The hypothesis of cancer stem cells has been proposed to explain the therapeutic failure in a variety of cancers including lung cancers. Previously, we demonstrated acquisition of epithelial–mesenchymal transition, a feature highly reminiscent of cancer stem-like cells, in gefitinib-resistant A549 cells (A549/GR). Here, we show that A549/GR cells contain a high proportion of CXCR4+ cells that are responsible for having high potential of self-renewal activity in vitro and tumorigenicity in vivo. A549/GR cells exhibited strong sphere-forming activity and high CXCR4 expression and SDF-1α secretion compared with parent cells. Pharmacological inhibition (AMD3100) and/or siRNA transfection targeting CXCR4 significantly suppressed sphere-forming activity in A549 and A549/GR cells, and in various non-small cell lung cancer (NSCLC) cell lines. A549/GR cells showed enhanced Akt, mTOR and STAT3 (Y705) phosphorylation. Pharmacological inhibition of phosphatidyl inositol 3-kinase or transfection with wild-type PTEN suppressed phosphorylation of Akt, mTOR and STAT3 (Y705), sphere formation, and CXCR4 expression in A549/GR cells, whereas mutant PTEN enhanced these events. Inhibition of STAT3 by WP1066 or siSTAT3 significantly suppressed the sphere formation, but not CXCR4 expression, indicating that STAT3 is a downstream effector of CXCR4-mediated signaling. FACS-sorted CXCR4+ A549/GR cells formed many large spheres, had self-renewal capacity, demonstrated radiation resistance in vitro and exhibited stronger tumorigenic potential in vivo than CXCR4− cells. Lentiviral-transduction of CXCR4 enhanced sphere formation and tumorigenicity in H460 and A549 cells, whereas introduction of siCXCR4 suppressed these activities in A549/GR cells. Our data indicate that CXCR4+ NSCLC cells are strong candidates for tumorigenic stem-like cancer cells that maintain stemness through a CXCR4-medated STAT3 pathway and provide a potential therapeutic target for eliminating these malignant cells in NSCLC.

Deposition of polychlorinated biphenyls and polybrominated diphenyl ethers in the vicinity of a steel manufacturing plant

Fang, M.,Choi, S.D.,Baek, S.Y.,Jin, G.,Chang, Y.S. Pergamon Press ; Elsevier [distribution] 2012 Atmospheric environment Vol.49 No.-

Spatial distribution and seasonal variation of polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) bulk deposition were investigated at four sites at and around an iron and steel making plant in Pohang, South Korea from January 2008 to May 2009. The steel complex site showed the highest average deposition fluxes of 74.0, 2.1, and 41.6 ng m<SUP>-2</SUP> day<SUP>-1</SUP> for @?<SUB>tri-deca</SUB>PCBs (Tri-DecaCBs), @?<SUB>12</SUB>PCBs (dioxin-like PCBs), and @?<SUB>8</SUB>PBDEs (8 PBDE congeners), respectively, indicating the steel complex is an important source of PCBs and PBDEs. The PCB deposition was dominated by Tri-TetraCBs and BDE209 was the most abundant PBDE congener. No clear seasonal variation of PCB and PBDE deposition was observed except at the steel complex site. Precipitation appeared to play an important role in the deposition distribution of PCBs, especially when the lowly chlorinated homologues dominated. In addition, the contribution of DL PCBs (dioxin-like PCBs) to the total TEQ (toxicity equivalent quantity) showed a seasonal variation and should not be neglected in the vicinity of a steel complex.

Immersed Heater-to-Bed Heat Transfer in a Pressurized Gas-Solid Fluidized Bed

Kang, Y 한국화학공학회 1997 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.35 No.2

대학생의 암 예방 수칙에 대한 인식 및 실천행태 연구

곽지연,김서연,김자영,이혜연,정문정,진수현,천선우,하소현,한희진,양숙자,김지연 이화여자대학교 간호과학대학 2016 이화간호학회지 Vol.- No.50

Purpose: The purpose of this study was to identify college student's perception and practice of 'National Cancer Prevention Actions' and the factors that influence the perception and practice. Method: The participants were 310 undergraduates selected by convenience sampling at colleges in Seoul. Instrument was 2014 Survey of Perception and Practice of National Cancer Prevention Actions by National Cancer Center(2014), and has been modified for the purpose of the study. The data were analyzed by t-test, ANOVA and Scheffe test with SPSS 23.0 Windows software. Results: The most recognized action for cancer prevention in college students was "Do not smoke, also avoid smoking smoke"(96.8%) while the most unrecognized was "Get a type B hepatitis vaccination"(58.7%). The most practiced action for cancer prevention in college students was "Sexually as to safe sex"(94.8%) while the most unpracticed was "Exercise five times a week or more, for at least 30 minutes a day"(33.9%). Among general characteristics, participants' age (t=-2.015, p<.05), major (F=3.109, p<.001), and residential type (F=4.959, p<.01) were statistically significant in the recognition of Cancer Prevention Actions and major(F=3.341 p<.05) and residential type(F=3.827, p<.05) were also significant in the practice of Cancer Prevention Actions. Among health characteristics, health concern(F=3.154, p<.05) and education in cancer(t=-3.112, p<.01) showed statistically significant differences in the recognition of Cancer Prevention Actions while health concern(F=7.896 p<.001) and subjective health status(F=9.913, p<.001) showed differences in the practice of Cancer Prevention Actions. Conclusion: These findings showed the gap between the perception and practice of cancer prevention actions. Considering the importance of individual characteristics, it is essential to develop a differentiated cancer prevention education program for college students. Also, nursing intervention program should be developed to raise the alertness of cancer in order to enhance cancer preventive practice.

유전자치료 효율향상을 위한 세포특이적 Vector의 개발

김계영,남명진,유천권,진동훈,백묘아,박만석,심수경,이혜경,이병철,박미연 국립보건연구원 2000 국립보건원보 Vol.37 No.-

Mycobacterium Avium - in tracellulare Complex 와 M . Fortuitum 에 의한 폐항산균증(肺抗酸菌症) 3예

김상재,홍수표,배길한,김성진,진병환,정충모 대한미생물학회 1982 大韓微生物學會誌 Vol.17 No.1

Two cases of pulmonary disease in a 54 year-old female and a 70 year-old male patient due to Mycobacterium avium-intracellulare complex (MAIC) and a case of pulmonary infection in a 69 year-old male patient due to M fortuitum (MF) were found recently in this institute. All three patients bad a long history of anti-tuberculous chemotherapy because they were initially diagnosed as pulmonary tuberculosis. A 70 year-old male patient infected with MAIC had an unsuccessful chemotherapy history of isoniazid (INH), para-aminosalicylic acid (PAS) and streptomycin (SM) with an incomplete, temporary, symptomatic improvement, for three years since 1964 when he was first diagnosed as pulmonary tuberculosis on physical examination. A 54 year-old female patient infected with MAIC also had an unsuccessful chemotherapy history with the various anti-tuberculous drugs since 1958. Both patients discharged large number of MAIC in their sputum specimens for at least more than one year, but no M tuberculosis at all. A 69 year-old male patient infected with MF was diagnosed as moderately advanced pulmonary tuberculsis in 1977. Combined chemotherapy with INH+PAS+pyrazinamide (PZA) improved his clinical symptoms, however, his chest radiograph was deteriorated again in 1980 one year after he stopped therapy. Therefore he started chemotherapy again with INH+ethionamide (TH)+cycloserine(CS) but no improvement was noticed. MF was cultured from his sputum in August 1983 and he continuously discharged the same baeilli until last examination of January l982. Whether all three patients were initially infected with nontuberculous mycobacteria or complicated with predisposing tuberculosis was not clear because there were no reliable bacteriological Examination records.