• 제목/요약/키워드: E2F

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Fe 치환이$LiMn_{2}O_{4}$정극 활물질의 충방전 특성에 미치는 영향 (Effect Of Substituted-Fe for the Charge-discharge behavior Of $LiMn_{2}O_{4}$cathode materials)

  • 정인성;김민성;구할본;손명모;이헌수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.548-551
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    • 2000
  • Spinel phase LiF $e_{y}$M $n_{2-y}$ $O_4$samples are synthesized by calcining a LiOH.$H_2O$, Mn $O_2$and F $e_2$ $O_3$mixture at 80$0^{\circ}C$ for 36h in air. Preparing LiF $e_{y}$M $n_{2-y}$ $O_4$showed spinel phase with cubic phase. The ununiform distortion of the crystallite of the spinel LiF $e_{y}$M $n_{2-y}$ $O_4$was more stable than that of the pure. The discharge capacity of the cathode for the Li/LiF $e_{0.1}$M $n_{1.9}$ $O_4$cell at the first than that of the pure. The discharge capacity of the cathode for the Li/LiF $e_{0.1}$M $n_{1.9}$ $O_4$cell at the first cycle and at the 70th cycle was about 113 and 90mAh/g, respectively. This cell capacity was retained about 82% of the first cycle after 70th cycle. Impedance profile of this cell was more stable than that pure. The resistance, the capacitance and chemical diffusion coefficients of lithium ion showed approximately 80$\Omega$, 36133.87$\mu$F ; 1.4$\times$10$^{-8}$ c $m^2$ $s^{-1}$ , respectively. , respectively.ely.

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4600계 소결강의 조직에 미치는 F$e_2$P첨가의 영향 (Effect of F$e_2$P Addition on Microstructures of Sintered 4600 Steel)

  • 김동욱;이완재
    • 한국재료학회지
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    • 제2권6호
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    • pp.428-435
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    • 1992
  • AISI 4600계 철 분말에 F$e_2$P 분말을 사용하여 인(P)을 0~1.0% 그리고 흑연 분말을 사용하여 탄소를 0~0.8% 첨가하여 회전혼합기를 사용하여 혼합하였다. 흔합분말을 양단압금형에서 800MPa로 가압하여 성형체를 만들었다. 성형체는 진공 또는 수소와 질소 혼합가스 분위기에서 115$0^{\circ}C$에서 30분간 소결하였다. 소결체를 연마하고 2% 질산용액으로 에칭하였다. 소결체 조직을 Image Analyzer와 금속현미경으로 관찰하였다. 밀도는 ASTM B3l2로, 경도는 미세 비커스경도기로 측정하였다. 얻어진 결과는 다음과 같다. (1) F$e_2$P 첨가량이 증가하면, 소결체 조직은 치밀화되고 입자 크기는 더 커졌다. (2) $Fe_2P량과$ 함께 기공의 형상은 둥글고, 그 숫자는 감소하였으나 평균크기는 더 커졌다. (3) 입자의 크기는 F$e_2$P와 흑연분말을 동시에 첨가한 경우가 각각 단독으로 첨가한 경우보다 커졌다. (4) 미세조직에 미치는 소결분위기의 영향은 거의 없었다. (5) 경도는 인과 탄소량이 증가하면 상승하였다.

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The Ubiquitin-Proteasome System and F-box Proteins in Pathogenic Fungi

  • Liu, Tong-Bao;Xue, Chaoyang
    • Mycobiology
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    • 제39권4호
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    • pp.243-248
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    • 2011
  • The ubiquitin-proteasome system is one of the major protein turnover mechanisms that plays important roles in the regulation of a variety of cellular functions. It is composed of E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 ubiquitin ligases that transfer ubiquitin to the substrates that are subjected to degradation in the 26S proteasome. The Skp1, Cullin, F-box protein (SCF) E3 ligases are the largest E3 gene family, in which the F-box protein is the key component to determine substrate specificity. Although the SCF E3 ligase and its F-box proteins have been extensively studied in the model yeast Saccharomyces cerevisiae, only limited studies have been reported on the role of F-box proteins in other fungi. Recently, a number of studies revealed that F-box proteins are required for fungal pathogenicity. In this communication, we review the current understanding of F-box proteins in pathogenic fungi.

THREE RESULTS ON TRANSCENDENTAL MEROMORPHIC SOLUTIONS OF CERTAIN NONLINEAR DIFFERENTIAL EQUATIONS

  • Li, Nan;Yang, Lianzhong
    • 대한수학회보
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    • 제58권4호
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    • pp.795-814
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    • 2021
  • In this paper, we study the transcendental meromorphic solutions for the nonlinear differential equations: fn + P(f) = R(z)eα(z) and fn + P*(f) = p1(z)eα1(z) + p2(z)eα2(z) in the complex plane, where P(f) and P*(f) are differential polynomials in f of degree n - 1 with coefficients being small functions and rational functions respectively, R is a non-vanishing small function of f, α is a nonconstant entire function, p1, p2 are non-vanishing rational functions, and α1, α2 are nonconstant polynomials. Particularly, we consider the solutions of the second equation when p1, p2 are nonzero constants, and deg α1 = deg α2 = 1. Our results are improvements and complements of Liao ([9]), and Rong-Xu ([11]), etc., which partially answer a question proposed by Li ([7]).

Li_{0.5}Fe_{2.5-x}Al_xO_4 페라이트계의 Mossbauer 스펙트럼 연구 (A Study OH Mossbauer Spectra Of the $Li_{0.5}Fe_{2.5-x}Al_xO_4$ Ferrite System)

  • 백승도
    • 한국자기학회지
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    • 제11권2호
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    • pp.58-62
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    • 2001
  • L $i_{0.5}$ F $e_{2.5-x}$A $l_{x}$ $O_4$ 페라이트계에 대한 XRD와 Mossbauer 스펙트럼을 측정 분석하였다. $Al^{3+}$ 씨온의 치환량 x가 증가할수록 격자상수는 작아지고, 값이 0, 0.3, 0.6인 시료에서는 두 site의 F $e^{3+}$ 이온에 의한 두 개의 6선 흡수선이 나타났고, x가 0.9, 1.2인 시료에서는 6선 흡수선외에 열에 의한 전자적 완화현상에 기인한 2선 흡수선이 공존하였으며, x가 1.5인 시료는 2선 흡수선만 나타났다. 공명흡수면적으로 계산된 L $i_{0.5}$ F $e_{2.5-x}$A $l_{x}$ $O_4$ 페라이트계의 금속 양이온 분포식은(L $i_{1-a}$$^{+}$F $e_{a}$ $^{3+}$ ) z으로 나타낼 수 있었고, 시료내의 $Al^{3+}$ 의 증가는 B-site의 F $e^{3+}$ - $O^{2-}$ 결합거리를 증가시켜 공유 결합성을 약화시키는 것으로 확인되었으며, $Al^{3+}$ 씨 증가에 따라 B-site의 F $e^{3+}$ 이온의 수가 감소하여 A-B 초 교환 상호 작용이 약화되는 것을 알 수 있었다.다.

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On the Order of Growth of Solutions to Complex Non-homogeneous Linear Differential Equations

  • Habib, Habib;Belaidi, Benharrat
    • Kyungpook Mathematical Journal
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    • 제56권3호
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    • pp.819-829
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    • 2016
  • In this paper, we study the order of growth of solutions to the non-homogeneous linear differential equation $$f^{(k)}+A_{k-1}e^{az}f^{(k-1)}+{\cdots}+A_1e^{az}f^{\prime}+A_0e^{az}f=F_1e^{az}+F_2e^{bz}$$, where $A_j(z)$ (${\not\equiv}0$) ($j=0,1,{\cdots},k-1$), $F_j(z)$ (${\not\equiv}0$) (j = 1, 2) are entire functions and a, b are complex numbers such that $ab(a-b){\neq}0$.

MCM promoter에서 E-box와 E2F 결합부위가 전사활성에 미치는 영향 (Effect of E-box and E2F Binding Site on Transcriptional Activity in MCM Promoter)

  • 권현주
    • 생명과학회지
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    • 제14권5호
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    • pp.732-740
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    • 2004
  • MCM 단백질의 암세포내에서 과발현 되는 원인을 규명하기 위하여 mcm7, 2 promoter영역의 전사인자 결합 부위의 역할을 조사하였다. 암세포에서 promoter 활성은 정상세포보다 8배정도 높은 활성을 나타내 특유 전사인자의 존재를 시사하였다. Promoter영 역 에는 E2F 결합부위 와 Myc/Max/Mad단백질 결합 부위로 알려진 I-box가 존재한다. 이들 각각의 변이체 promoter를 작성하여 암세포와 정상세포에서 luciferase reporter 활성을 측정하는 것으로 각 영역의 역할을 검토하였다. 그 결과 정상세포 내에서는 강한 repressor존재 또는 활성을 negative로 조절 할 수 있는 complex의 존재로 promoter활성이 조절되는 반면 암세포 내에서는 I-box에 결합하여 promoter를 활성화시키는 특유 단백질의 존재가 시사되었다.

EXISTENCE OF TRANSCENDENTAL MEROMORPHIC SOLUTIONS ON SOME TYPES OF NONLINEAR DIFFERENTIAL EQUATIONS

  • Hu, Peichu;Liu, Manli
    • 대한수학회보
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    • 제57권4호
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    • pp.991-1002
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    • 2020
  • We show that when n > m, the following delay differential equation fn(z)f'(z) + p(z)(f(z + c) - f(z))m = r(z)eq(z) of rational coefficients p, r doesn't admit any transcendental entire solutions f(z) of finite order. Furthermore, we study the conditions of α1, α2 that ensure existence of transcendental meromorphic solutions of the equation fn(z) + fn-2(z)f'(z) + Pd(z, f) = p1(z)eα1(z) + p2(z)eα2(z). These results have improved some known theorems obtained most recently by other authors.

국내 분리 돼지 부종병 대장균의 병원성 유전자 및 시가독소 생성 검증 (Evaluation of the virulence genes and Shiga toxin-producing abilities of Escherichia coli field isolates causing edema disease in pigs)

  • 서병주;정창기;강아름;조호성;김원일
    • 한국동물위생학회지
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    • 제39권2호
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    • pp.87-92
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    • 2016
  • Porcine edema disease (ED) is a communicable disease of pigs caused by infection with Shiga toxin (Stx)-producing Escherichia coli (STEC) which expresses F18 fimbriae and/or Stx type 2e (Stx2e). While STEC causes a severe illness including hemorrhagic colitis and hemolytic-uremic syndrome in humans, it induces damage to the vascular endothelium, which results in edema, hemorrhage, and microthrombosis, leading in high mortality in pigs. In the present study, we cultured Stx2e-producing E. coli field isolates from conventional pig farms that experienced sudden deaths previously with symptoms similar to porcine edema disease, which were further investigated with Shiga toxin profiles. A total of 43 strains were identified from the collected samples by F18 or Stx2e specific PCR. Based on the PCR, 42 isolates out of 43 isolates were proved to carry one of F18 or Stx2e genes and 14 isolates to carry both F18 and Stx2e genes. All of the 30 isolates that harbored Stx2e gene induced the cytopathic effect (CPE) in vero cells and especially, the isolate 150229 produced the highest level of Shiga toxin. Therefore, we identified the virulence genes (F18 and Stx2e) and demonstrated Shiga toxin-producing abilities from porcine edema disease causing E. coli filed isolates. These results suggested that one of the isolates could be a vaccine antigen candidate against STEC through further investigating to elicit an immune response.

$C_4F_{8}O_2$ 공정기체와 E-ICP를 이용한 산화막 식각 ($SiO_2$ Etching in $C_4F_{8}$ Plasma by E-ICP)

  • 송호영;조수범;이종근;오범환;박세근
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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    • pp.197-200
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    • 2001
  • Novel Enhanced Inductively Coupled Plasma is applied to etch $SiO_2$. Effect of $O_2$ or Ar addition to $C_{4}F_{8}$ gas is monitored by Optical Emission Spectroscopy and Quadrupole Mass Spectrometer. It is fund that Ar or $O_2$ dilution to $C_{4}F_{8}$ increases F emission intensity and decreases $CF_2$ intensity. However, the ac frequency to the Helmholtz coil decreases the F intensity and thus increases $CF_2$/F ratio. By adjusting the ac frequency, the optimum etch rate and PR to $SiO_2$ selectivity can be obtained in E-lCP.

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