• Title/Summary/Keyword: f factor

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Role of E2F1 in Endoplasmic Reticulum Stress Signaling

  • Park, Kyung Mi;Kim, Dong Joon;Paik, Sang Gi;Kim, Soo Jung;Yeom, Young Il
    • Molecules and Cells
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    • v.21 no.3
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    • pp.356-359
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    • 2006
  • The transcription factor E2F1 coordinates cell cycle progression and induces apoptosis in response to DNA damage stress. Aside from DNA damage, the role of E2F1 in the endoplasmic reticulum (ER) stress signaling pathways is unclear. We found that $E2F1^{-/-}$ murine embryonic fibroblasts (MEFs) are resistant to apoptosis triggered by the ER stress inducer thapsigargin. In addition, E2F1 deficiency results in enhanced phosphorylation of eukaryotic translation initiation factor $2{\alpha}$ ($elF2{\alpha}$). These results therefore indicate that E2F1 deficiency increases phosphorylation of $elF2{\alpha}$ in response to ER stress triggered by thapsigargin, and suggest that the reduction in ER stress-induced apoptosis in E2F1-deficient cells is related to the high level of $elF2{\alpha}$ phosphorylation.

An Experimental Study on the Effect of the Air Temperature on the Air-Side Heat-Transfer Coefficient and the Friction Factor of a Fin-and-Tube Heat Exchanger (외기 온도 변화가 핀-관 열교환기의 공기측 열전달계수와 마찰계수에 미치는 영향에 관한 실험적 연구)

  • Kim, Nae-Hyun;Cho, Honggi
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.4
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    • pp.149-158
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    • 2017
  • In general, the air-side j and f factors of evaporators or condensers are obtained through single-design tests performed under air-dry and wet-bulb temperatures. Considering that the indoor or outdoor air temperatures vary significantly during the operation of an air conditioner, it is necessary to confirm that the experimentally-obtained j and f factors are widely applicable under variable air conditions. In this study, a series of tests were conducted on a two-row slit-finned heat exchanger to confirm the applicability. The results showed that, for the dry-surface condition, the changes of the tube-side water temperature, water-flow rate, and air temperature had virtually no effect on the air-side j and f factors. For the wet condition, however, the f factor was significantly affected by these changes; contrarily, the j factor is relatively independent regarding this change. The formulation of the possible reasoning is in consideration of the condensation behavior underneath the tube. The wet-surface j and f factors are larger than those of the dry surface, with a larger amount for the f factor.

NOTE ON CONNECTED (g, f)-FACTORS OF GRAPHS

  • Zhou, Sizhong;Wu, Jiancheng;Pan, Quanru
    • Journal of applied mathematics & informatics
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    • v.28 no.3_4
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    • pp.909-912
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    • 2010
  • In this note we present a short proof of the following result by Zhou, Liu and Xu. Let G be a graph of order n, and let a and b be two integers with 1 $\leq$ a < b and b $\geq$ 3, and let g and f be two integer-valued functions defined on V(G) such that a $\leq$ g(x) < f(x) $\leq$ b for each $x\;{\in}\;V(G)$ and f(V(G)) - V(G) even. If $n\;{\geq}\;\frac{(a+b-1)^2+1}{a}$ and $\delta(G)\;{\geq}\;\frac{(b-1)n}{a+b-1}$,then G has a connected (g, f)-factor.

Power Comparison in a Balanced Factorial Design with a Nested Factor

  • Choi, Young-Hun
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.4
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    • pp.1059-1071
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    • 2008
  • In a balanced factorial design with a nested factor where crossed factors as well as a nested factor exist simultaneously, powers of the rank transformed FR statistic for testing the main, nested and interaction effects are superior to those of the parametric F statistic. In heavy tailed distributions such as exponential and double exponential distributions, powers of the FR statistic show much higher level than those of the F statistic. Further powers of the F and FR statistic for testing the main effect show the highest level in an absolute size as compared with powers of the F and FR statistic for testing the nested and interaction effects. However powers of the FR statistic for testing the nested and interaction effects rather than the main effect are greater in a relative size than powers of F statistic for the all population distributions.

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RANDOMLY ORTHOGONAL FACTORIZATIONS OF (0,mf - (m - 1)r)-GRAPHS

  • Zhou, Sizhong;Zong, Minggang
    • Journal of the Korean Mathematical Society
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    • v.45 no.6
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    • pp.1613-1622
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    • 2008
  • Let G be a graph with vertex set V(G) and edge set E(G), and let g, f be two nonnegative integer-valued functions defined on V(G) such that $g(x)\;{\leq}\;f(x)$ for every vertex x of V(G). We use $d_G(x)$ to denote the degree of a vertex x of G. A (g, f)-factor of G is a spanning subgraph F of G such that $g(x)\;{\leq}\;d_F(x)\;{\leq}\;f(x)$ for every vertex x of V(F). In particular, G is called a (g, f)-graph if G itself is a (g, f)-factor. A (g, f)-factorization of G is a partition of E(G) into edge-disjoint (g, f)-factors. Let F = {$F_1$, $F_2$, ..., $F_m$} be a factorization of G and H be a subgraph of G with mr edges. If $F_i$, $1\;{\leq}\;i\;{\leq}\;m$, has exactly r edges in common with H, we say that F is r-orthogonal to H. If for any partition {$A_1$, $A_2$, ..., $A_m$} of E(H) with $|A_i|=r$ there is a (g, f)-factorization F = {$F_1$, $F_2$, ..., $F_m$} of G such that $A_i\;{\subseteq}E(F_i)$, $1\;{\leq}\;i\;{\leq}\;m$, then we say that G has (g, f)-factorizations randomly r-orthogonal to H. In this paper it is proved that every (0, mf - (m - 1)r)-graph has (0, f)-factorizations randomly r-orthogonal to any given subgraph with mr edges if $f(x)\;{\geq}\;3r\;-\;1$ for any $x\;{\in}\;V(G)$.

Cloning and Expression of Human Clotting Factor 9 cDNA un Escherichia coli (인체 혈액응고 9인자 cDNA cloning 및 Escherichia coli 에서의 발현)

  • Young Won Lee;Hyang Suk Hur;Myoung Hee Kim
    • Biomedical Science Letters
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    • v.2 no.2
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    • pp.231-240
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    • 1996
  • Human blood clotting (coagulation) factor 9 cDNA which codes for 461 amino acid has been cloned by screening human fetal liver cDNA library using PCR. This 1.4 kb cDNA spanning from the ATG initiation codon to the TAA termination codon was cloned into bacterial .expression vector pGEX-2T, generating pGEX-F9 plasmid. The plasmid pGEX-F9 expresses about 73 kDa GST (Glutathione S-transferase)-Factor 9 fusion protein when introduced into E. coli. Western blot analysis using polyclonal antibody raised against human factor 9 confirmed this fusion protein contains factor 9 protein. The level of GST-factor 9 expression was about 20% of total protein and the purification of fusion protein was efficiently achieved by using GST agarose bead based on one step purification protocol.

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The Relationship Between Delamination Element and Delamination Growth (층간분리 요소와 층간분리 성장의 관계)

  • 송삼홍;김철웅;홍정화;김태수;황진우
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2003.04a
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    • pp.113-116
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    • 2003
  • The investigation of delamination growth behavior in hybrid composite material such as FRMLs should be considered delamination growth rate, dA_D/da$ using the delamination shape factor, $f_S$ instead of traditional fracture mechanics parameters. The main objective of this study is to evaluate the relationship between delamination element (i. e. delamination width, b, delamination contour, c, delamination shape factor, $f_S$ and delamination growth rate, dA_D/da$) and delamination growth in FRMLs under cyclic bending moment. The delamination shape formed along the fatigue crack between aluminum layer and glass fiber/epoxy layer are measured by scanning method. The details of study are as follow : ⅰ) Relationship between crack length, a and delamination width, b. ⅱ) Variation of delamination growth rate, dA_D/da$ was attendant on delamination shape factors, $f_{S1}$, $f_{S2}$, $f_{S3}$. The test result indicated the delamination growth behavior depends in delamination element such as delamination width, b, delamination shape factors, $f_{S1}$, $f_{S2}$, $f_{S3}$.

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Identifying and Sequencing of the Elementary Minor Concepts of the Highest Common Factor (H.C.F.) and the Lowest Common Multiple (L.C.M.) of Numbers

  • Alam, S. K. Samsul
    • Research in Mathematical Education
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    • v.13 no.1
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    • pp.49-61
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    • 2009
  • In this paper some attempts have been made: (a) To identify all the elementary minor concepts of the Highest Common Factor (H.C.F.) and the Lowest Common Multiple (L.C.M.), and (b) To find the sequential order of these elementary concepts. Total 385 elementary minor concepts have been identified and sequenced.

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Microwave Dielectric Properties of (1-x)ZnWO4-xTiO2 Ceramics ((1-x)ZnWO4-xTiO2 세라믹스의 마이크로파 유전특성)

  • 윤상옥;김대민;심상흥;강기성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.5
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    • pp.397-403
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    • 2003
  • Microwave dielectric properties of (1-x)ZnW $O_4$-xTi $O_2$ ceramic systems were investigated with calcination temperatures and Ti $O_2$ contents. The ZnW $O_4$ ceramic could be suitably sintered at 1075$^{\circ}C$ and showed the dielectric constant of 13.6, quality factor(Q$\times$ $f_{O}$value) of 22,000 and temperature coefficient of resonant frequency($\tau$$_{f}$) of -65$\pm$2ppm/$^{\circ}C$. Increasing the amount of Ti $O_2$ in the range of 0.25 to 0.45 mol, the dielectric constant and $\tau$$_{f}$ increased due to the role of Ti $O_2$ but the quality factor decreased due to the increase of phase boundaries. The 0.7ZnW $O_4$-0.3Ti $O_2$ ceramic showed the dielectric constant of 19.8, qualify factor(Q$\times$ $f_{0}$) of 20,000 and $\tau$$_{f}$ of -3$\pm$1ppm/$^{\circ}C$.>.EX>.>.>.

Understanding of F2 Metrics Used to Evaluate Similarity of Dissolution Profiles (유사인자를 사용하여 용출양상 유사성을 비교하는 방법에 대한 고찰)

  • Cho, Mi-Hyun;Kim, Jeong-Ho;Lee, Hyeon-Tae;Sah, Hong-Kee
    • Journal of Pharmaceutical Investigation
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    • v.33 no.3
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    • pp.245-253
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    • 2003
  • Dissolution profile comparsions can be done by virtue of the similarity factor $(f_2)$. It is a logarithmic reciprocal square root transformation of the sum of squared error of % dissolution differences between two profiles at several time points. It gives information on the degree of similarity between the two profiles: An $f_2$ value between 50 and 100 suggests the similarity/equivalence of the two dissolution curves being compared. The objective of this report was to provide a careful examination on the $f_2$ metrics in detail. It was shown that $f_2$ values exceeded 50, when relative differences in % dissolved between two products were less than 15% at all time points. The similarity factor value was also found to be greater than 50, in cases when absolute % dissolution differences were below 10% at all time points. Interestingly, the $f_2$ value was changed by the number of the time points selected for calculation. In particular, $f_2$ tended to have higher values, when the $f_2$ metrics used a large number of time points in which % dissolved reached plateau. Finally, since the similarity factor was a sample statistics, it was impossible to infer type I/II errors and sampling error. Despite certain limitations inherited in the $f_2$ metrics, it was easy and convenient to evaluate how similar the two dissolution profiles were.