• Research in Plant Disease
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• v.10 no.4
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• pp.248-259
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• 2004

A total 115 isolates of Fusarium species from ginseng roots of 'rotted', and soils collected during 1982-1985 in Korea, were identified and classified into 11 species with the Snyder & Hansen System (with reference to Gerlach-Nirenberg's Modified System). The most dominant of these species were F. solani (55 isolates), F. oxysporum (35 isolates), and F. moniliforme (10 isolates) sensu Snyder & Hansen. The other 8 species (15 isolates) were very rarely isolated and previously identified as F. roseum sensu Snyder & Hansen (1945); these were F. equiseti, F. avenaceum, F. graminum, F. arthrosporioides, F. sambucinum, F. reticulatum, F. semitectum and F. poa. Tested for the ability to infect the roots of ginseng (3 yr. old plants) in field condition with the mycelial inoculum, only one isolate of F. solani (34 isolates tested) and one isolate of F. oxysporum (24 isolates tested) were weakly pathogenic to ginseng roots. Any of the isolates (7 isolates tested) of F. moniliforme [Liseola section] were not pathogenic to ginseng. However, all the isolates of tested of the species of Phytophthora cactorum, Pythium ultimum, and Cylindrocarpon destructans were highly pathogenic to ginseng roots. The species of Fusarium solani and Cylindrocarpon destructans were supposed to be a host dominant disease agent in ginseng plant.

• Communications of the Korean Mathematical Society
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• v.13 no.1
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• pp.77-84
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• 1998

In this note we show that if $T_{\varphi}$ is a Toeplitz operator with quasicontinuous symbol $\varphi$, if $\omega$ is an open set containing the spectrum $\sigma(T_\varphi)$, and if $H(\omega)$ denotes the set of analytic fuctions defined on $\omege$, then the following statements are equivalent: (a) $T_\varphi$ is semi-quasitriangular. (b) Browder's theorem holds for $f(T_\varphi)$ for every $f \in H(\omega)$. (c) Weyl's theorem holds for $f(T_\varphi)$ for every $f \in H(\omega)$. (d) $\sigma(T_{f \circ \varphi}) = f(\sigma(T_varphi))$ for every $f \in H(\omega)$.

• Kyungpook Mathematical Journal
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• v.47 no.3
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• pp.449-454
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• 2007

InIn this paper we consider generalizations of the classical Dixon's theorem and the classical Whipple's theorem on the sum of a $_3F_2$. The results are derived with the help of generalized Watson's theorem obtained earlier by Mitra. A large number of results contiguous to Dixon's and Whipple's theorems obtained earlier by Lavoie, Grondin and Rathie, and Lavoie, Grondin, Rathie and Arora follow special cases of our main findings.

• East Asian mathematical journal
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• v.17 no.2
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• pp.233-237
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• 2001

The authors aim at presenting summation formulas of Appell's function $F_1$: $$F_1(a;b,b';1+a+b-b'+i;1,-1)\;(i=0,\;{\pm}1,\;{\pm}2,\;{\pm}3,\;{\pm}4,\;{\pm}5)$$, which, for i=0, yields a known result due to Srivastava.

• East Asian mathematical journal
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• v.17 no.2
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• pp.197-215
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• 2001

A generalised Taylor series with integral remainder involving a convex combination of the end points of the interval under consideration is investigated. Perturbed generalised Taylor series are bounded in terms of Lebesgue p-norms on $[a,b]^2$ for $f_{\Delta}:[a,b]^2{\rightarrow}\mathbb{R}$ with $f_{\Delta}(t,s)=f(t)-f(s)$.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.56-62
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• 1989

Antagonistic effects of Streptomyces species aganinst Fusarium solani causing ginseng root rot were investigated in terms of chitinase activity and growth inhibition in vitro. Among 131 isolates of streptomycetes obtained from ginseng cultivating soil, 9 isolates producing large clear zone around the colony on a chitin agar medium were selected for further study. All 9 isolates produced chitinase in a range from 0.10 to 0.38 U lysing cells of F. solani and inhibited germination of the conidia. In the ten-fold condentrated culture filtrate of S. alboniger ST59 and S. roseolilacinus ST129, the number of conidia of F. solane was reduced to about 20% of original count within 14 days. When S. alboniger ST59 and F. solani were grown simultaneously in the mineral saly medium, chitinase activity increased with incubation period, whereas mycelial volume of F. solani decreased. In a chitin added mineral salt medium, chitinase activity increased during the first four days and maintained steady level until the 8th day, and increased thereafter. S. alboniger ST59 lysed mycelia, conidia and even chlamydospores of F. solani. It is probable that the antagonistic activity of this streptomycete against F. solani is the lysis of fungal cell wall by streptomycete producing chitinase affected by antifungal substances.

• Composites Research
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• v.26 no.3
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• pp.189-194
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• 2013

This paper deals with the study of mechanical properties and impact energy absorbed by composites, made by using thermoplastic and thermoset as matrix, flax fiber and nanoclay as reinforcements. The nanoclay was sprayed on the fiber laminate directly after mixing with ethanol. This experiment designed by Taguchi method and have variable factors, i.e three types of fiber direction(F), three different nanoclay wt%(N) and three spray gun hole shapes(S). According to these conditions, composites were made and the optimum conditions were found to be F1N3S1, F1N2S1, F1N2S1 and F3N2S1 for thermoplastic, and F1N3S2, F1N3S2, F1N2S2 and F3N2S1 for thermoset which were matched with tensile strength, modulus, total impact absorbed energy and heat release rate respectively.

• Analytical Science and Technology
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• v.14 no.2
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• pp.191-195
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• 2001

Cucurbitacin D and F, the protostane type triterpenoid of S. sorbifolia, were isolated with chromatograpic method and used as the standard substances for quantitative analysis. The compounds were identified with $^1H$-NMR, FAB-MS and UV spectrophotometer. They were separated on YMC-Pack ODS-AQ(303)[$250{\times}4.6mm$ I.D., $S-5{\mu}m$, 120A] column by HPLC. Cucurbitacin F was detected at 10.73mg/kg in cortex of S. sorbifolia, but cucurbitacin D was not. The compounds were shown to exihibit significant cytotoxicity($ED_{50}$<$0.1{\mu}g/mL$) against several tumor cell lines and acute toxicity(cucurbitacin D: 4.7mg/kg/day, cucurbitacin F: 2.5mg/kg/day) against BDF-1 mouse.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.2
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• pp.133-138
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• 2010

The purpose of this study was to survey and test quality control of mammography system. The conclusion of this study is as follows ; First, The rate of pass for phantom image test shows that Film-Screen mammography system(F/S) and computed mammography system(CR) is 80%, Indirect digital mammography system(DR) is 100%. Second, The test of exposure dose shows that F/S is 921 mR. CR is 1,140 mR, DR is 474 mR. The grade of this testament is CR > F/S > DR. Third, The test of average glandular dose shows that F/S is 1,336 mGy, CR is 1,635 mGy, DR is 1,26 mGy. The grade of this testament is CR > F/S > DR. Fourth, The testament of resolution shows as follows F/S is 11~13 Lp/mm, CR is 4~5 Lp/mm, and DR is 5~7 Lp/mm(F/S > DR > CR) Fifth, The survey of projection, cassette, development and reading shows that user are indifference.

• Communications of the Korean Mathematical Society
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• v.31 no.3
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• pp.533-547
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• 2016

In this paper, a generalized boundary version of $Carath{\acute{e}}odory^{\prime}s$ inequality for holomorphic function satisfying $f(z)= f(0)+a_pz^p+{\cdots}$, and ${\Re}f(z){\leq}A$ for ${\mid}z{\mid}$<1 is investigated. Also, we obtain sharp lower bounds on the angular derivative $f^{\prime}(c)$ at the point c with ${\Re}f(c)=A$. The sharpness of these estimates is also proved.