• Korean Journal of Mathematics
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• v.26 no.1
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• pp.75-85
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• 2018

In this paper, we study nonconstant warping functions on an Einstein warped product manifold $M=B{\times}_{f^2}F$ with a warped product metric $g=g_B+f(t)^2g_F$. And we consider a 2-dimensional base manifold B with a metric $g_B=dt^2+(f^{\prime}(t))^2du^2$. As a result, we prove the following: if M is an Einstein warped product manifold with a 2-dimensional base, then there exist generally nonconstant warping functions f(t).

• Bulletin of the Korean Mathematical Society
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• v.61 no.4
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• pp.959-968
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• 2024

Suppose f belongs to the Bloch space with f(0) = 0. For 0 < r < 1 and 0 < p < ∞, we show that $$M_p(r,\,f)\,=\,({\frac{1}{2\pi}}{\int_{0}^{2\pi}}\,{\mid}f(re^{it}){\mid}^pdt)^{1/p}\,{\leq}\,({\frac{{\Gamma}(\frac{p}{2}+1)}{{\Gamma}(\frac{p}{2}+1-k)}})^{1/p}\,{\rho}{\mathcal{B}}(log\frac{1}{1-r^2})^{1/2},$$ where ρʙ(f) = sup_z∈ⅅ(1 - |z|²)|f'(z)| and k is the integer satisfying 0 < p - 2k ≤ 2. Moreover, we prove that for 0 < r < 1 and p > 1, $${\parallel}f_r{\parallel}_{B_q}\,{\leq}\,r\,{\rho}{\mathcal{B}}(f)(\frac{1}{(1-r^2)(q-1)})^{1/q},$$ where f_r(z) = f(rz) and ||·||ʙ_q is the Besov seminorm given by ║f║ʙ_q = (∫_𝔻 |f'(z)|^q(1-|z|²)^q-2dA(z)). These results improve previous results of Clunie and MacGregor.

• Korean Journal of Microbiology
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• v.32 no.2
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• pp.120-125
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• 1994

The genes, trpB, trpA and 3’ trpC(F) of Vibrio metschnikovii strain RH530 were cloned and sequenced. The trpB and trpA genes had open reading frames of 1,173 bp and 804 bp encoding 391 and 268 amino acids, respectively. The trpB and trpA genes had conventional ribosome-binding sequences and overlapped with each other by one nucleotide, suggesting that these two genes are translationally coupled. 115 nucleotide upstream the trpB start codon, tjere was an incomplete open reading frame of the 3’-end of the trpC(F). The amino acid sequences of trpB, trpA and trpC(F) of V. metschnikovii RH530 had identities of 64.2%, 82.4% and 73.7% respectively, for those of V. parahaemolyticus; 58.7%, 72.3% and 54.9%, respectively, for Salmonella typhimurium; and 42.6%. 54.1% and 12.5%, respectively, for brevibacterium lactofermentum. The genetic organization of these genes, especially in the noncoding region between trpC(F) and trpB, was distinct from that of Enterobacteriaceae.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.192-196
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• 1985

Eight strains of Lactobacilli(a, b, b', c, d, e, f and g) were isolated from seven Korean liquid-yogurts(A, B, C, D, E, F and G), and identification and tolerance-test to digestive fluids were carried out. Isolate a from yogurt A and isolate a from yogurt E were identified as L. casei, isolate b from yogurt B as L. acidophilus, isolate d from yogurt D as L. bulgaricus, isolate f from yogurt F as L. helveticus, and isolate b' from yogurt B, isolate c from yogurt C and isolate g from yogurt G as L. jugurti, respectively. Isolate f(L. helveticus) and c(L. jugurti) showed high tolerance to artificial gastric juice but didn't to bile acid. Isolate b(L. acidophilus), a(L. casei), and e(L. casei) showed high tolerance to both artificial gastric juice and bile acid, but isolate d(L. bulgaricus), b'(L. jurgurti) and g(L. jugurti) did not.

• Korean Journal of Mathematics
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• v.7 no.2
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• pp.183-198
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• 1999

Let $\mathcal{F}(B)$ be the Fresnel class on an abstract Wiener space (B, H, ${\omega}$) which consists of functionals F of the form : $$F(x)={\int}_H\;{\exp}\{i(h,x)^{\sim}\}df(h),\;x{\in}B$$ where $({\cdot}{\cdot})^{\sim}$ is a stochastic inner product between H and B, and $f$ is in $\mathcal{M}(H)$, the space of all complex-valued countably additive Borel measures on H. We introduce the concepts of an $L_p$ analytic Fourier-Feynman transform ($1{\leq}p{\leq}2$) and a convolution product on $\mathcal{F}(B)$ and verify the existence of the $L_p$ analytic Fourier-Feynman transforms for functionls in $\mathcal{F}(B)$. Moreover, we verify that the Fresnel class $\mathcal{F}(B)$ is closed under the $L_p$ analytic Fourier-Feynman transform and the convolution product, respectively. And we investigate some interesting properties for the $n$-repeated $L_p$ analytic Fourier-Feynman transform on $\mathcal{F}(B)$. Finally, we show that several results in [9] come from our results in Section 3.

• Journal of the Korean Mathematical Society
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• v.43 no.3
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• pp.579-591
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• 2006

In this paper we obtain a sufficient and necessary condition for an analytic function f on the unit ball B with Hadamard gaps, that is, for $f(z)\;=\;{\sum}^{\infty}_{k=1}\;P_{nk}(z)$ (the homogeneous polynomial expansion of f) satisfying $n_{k+1}/n_{k}{\ge}{\lambda}>1$ for all $k\;{\in}\;N$, to belong to the weighted Bergman space $$A^p_{\alpha}(B)\;=\;\{f{\mid}{\int}_{B}{\mid}f(z){\mid}^{p}(1-{\mid}z{\mid}^2)^{\alpha}dV(z) < {\infty},\;f{\in}H(B)\}$$. We find a growth estimate for the integral mean $$\({\int}_{{\partial}B}{\mid}f(r{\zeta}){\mid}^pd{\sigma}({\zeta})\)^{1/p}$$, and an estimate for the point evaluations in this class of functions. Similar results on the mixed norm space $H_{p,q,{\alpha}$(B) and weighted Bergman space on polydisc $A^p_{^{\to}_{\alpha}}(U^n)$ are also given.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.129-135
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• 1994

Ninety-two isolates of Fusarium species were obtained from Chinese corn samples. The predominant Fusarium species isolated from corn seeds were F. moniliforme, F. proliferatum, F. oxysporum and F. subglutinans, and all 13 species were identified. Each isolate was grown on autoclaved wheat grains and wheat cultures were fed by twenty-one-day-old female rats for the toxicity test. Twenty-six out of 92 isolates caused the death accompanying feed refusal, severe weight loss, liver damage, and hemorrhages in the stomach and intestines. Of the toxigenic isolates, 17 isolates of F. moniliforme, 4 of F. oxysporum, 3 of F. proliferatum, and one of each F. sporotrichioides and unknown species were lethal to rats. The analyses of fumonisin B1 production of the 26 toxigenic Fusarium isolates were carried out by thin layer chromatography and high-performance liquid chromatography, and fumonisin B1 was confirmed by mass spectrometry. Fumonisin B1 was produced in wheat culture at levels ranging from 280 $\mu\textrm{g}$/g to 3,952 $\mu\textrm{g}$/g by all of toxigenic F. moniliforme and F. proliferatum, but by none of the other toxigenic Fusarium species. The present results suggest the high possibility of natural occurrence of fumonisin B1 in corn samples imported from China.

• Bulletin of the Korean Mathematical Society
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• v.55 no.2
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• pp.573-586
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• 2018

Let R be a noncommutative prime ring of characteristic different from 2, Q be its maximal right ring of quotients and C be its extended centroid. Suppose that $f(x_1,{\ldots},x_n)$ be a noncentral multilinear polynomial over $C,b{\in}Q,F$ a b-generalized derivation of R and d is a nonzero derivation of R such that d([F(f(r)), f(r)]) = 0 for all $r=(r_1,{\ldots},r_n){\in}R^n$. Then one of the following holds: (1) there exists ${\lambda}{\in}C$ such that $F(x)={\lambda}x$ for all $x{\in}R$; (2) there exist ${\lambda}{\in}C$ and $p{\in}Q$ such that $F(x)={\lambda}x+px+xp$ for all $x{\in}R$ with $f(x_1,{\ldots},x_n)^2$ is central valued in R.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.63-75
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• 2009

The aim of this study was to elucidate the antimelanogenic effect of Dokhwalkisaeng-tang(Duohujisheng-tang) in B16F10 melanoma cells. Dokhwalkisaeng-tang(DKT) was used to develop the effective prescription of inhibition of melanin production. We determined inhibitory effects of DKT on melanin-release, melanin production, and tyrosinase activity in B16F10 melanoma cells. And to explicate the action-mechanism of DKT, melanin-related gene expressions were determined using RT-PCR and real time RT PCR technique in B16F10 melanoma cells. DKT inhibited melanin-release, melanin production in B16F10 melanoma cells considerably. DKT inhibited tyrosinase activity in vitro and in B16F10 melanoma cells. DKT inhibited the expression of tyrosinase, TRP-1, TRP-2 in B16F10 melanoma cells. DKT inhibited the expression of PKA, PKC, MMP-2 and MITF in B16F10 melanoma cells. On the other hand, DKT increased the expression of ERK-1, ERK-2, AKT-1 in B16F10 melanoma cells. From these results, we propose that DKT may have effect on the antimelanogenesis.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.717-720
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• 2008

This study analyzed the basic characteristics and the characteristic of drying shrinkage and creep of high performance concrete complexly metathesized by BS and FA and the results are summarized as the followings. Regarding to the compressive strengths according to the passage of aging, OPC was appeared to be larger than B2F1 at the initial aging but B2F1 was appeared to be higher than OPC at aging 28days. Regarding to the changing rate of drying shrinkage according to the passage of aging, both OPC and B2F1 were appeared to be increased and, at aging 60days, B2F1 was appeared to be largely increased by about 42% as -21${\times}$10-6 및 -51${\times}$10-6 as compared to OPC. The transforming rate of creep was appeared to have been largely increased at the initial aging and then be smoothly increased somewhat as the aging was passed. And regardign to the transforming rate of creep after 60 days had been passed, B2F1 was appeared to be largely increased by about 13% as compared to OPC.