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Diversity and Pathogenicity of Fusarium Species Associated with Head Blight of Job's Tears (율무 이삭마름 증상에서 분리한 Fusarium속 균의 다양성 및 병원성)

  • Choi, Hyo-Won;Hong, Sung-Kee;Kim, Wan-Gyu;Lee, Young-Kee
    • The Korean Journal of Mycology
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    • v.39 no.3
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    • pp.217-222
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    • 2011
  • Job's tears (Coix lacryma-jobi) is native to East Asia, and grains of the plant are used as health food and medicinal material. Head blight symptoms of the plant were frequently observed during disease surveys in Korea from 2006 to 2008. The symptoms were characterized as discoloration of husks, and subsequently inside of mature grains were shriveled or emptied. One hundred fifty nine isolates of Fusarium species were obtained from the disease symptoms of the plant collected from several locations in the country. Out of the isolates, the most frequently isolated Fusarium species were F. graminearum (34%), F. proliferatum (14.5%), F. verticillioides (10.1%), F. equiseti (6.9%), and F. fujikuroi (6.3%). Other Fusarium species isolated were F. subglutinans, F. semitectum, F. poae, and F. sporodochioides. Elongation factor 1 alpha gene sequences of the isolates were used for phylogenetic analysis. Analyses of the sequences revealed that the isolates were confirmed to be identical with each reference species of NCBI GenBank. Pathogenicity tests showed that F. graminearum, F. proliferatum and F. verticillioides were strongly virulent to grains of Job's tears. The present study is the first report of head blight of Job's tears caused by Fusarium species in Korea.

Biological activity of crude polyphenol fractions of Cedrela sinensis isolated using different extraction methods (참죽의 추출방법에 따른 폴리페놀 분획의 생리기능성)

  • Oh, Min Hui;Yoon, Kyung Young
    • Korean Journal of Food Science and Technology
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    • v.49 no.4
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    • pp.438-443
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    • 2017
  • The biological activity of crude polyphenol fractions (WphF, EphE, VphF, and SphF) extracted from Cedrela sinensis using hot water, ethanol, and enzymes such as Viscozyme and Shearzyme was examined in this study. The yield of VphF was the highest (43.44%) among all fractions. The total polyphenol and flavonoid content of the fractions were highest after ethanol extraction (447.98 and 337.49 mg/g, respectively). Fractions obtained after hot water and ethanol treatment showed high antioxidant activity. All fractions, except for WphF, showed a significantly higher ${\alpha}$-glucosidase inhibitory activity than the acarbose. EphF and WphF showed the high acetylcholinesterase inhibition activity. All fractions showed more than 50% tyrosinase inhibition activity at 2 mg/mL concentration. According to these results, the crude polyphenol fractions from C. sinensis showed high antioxidative, ${\alpha}$-glucosidase inhibitory, and tyrosinase inhibitory activities. This study suggests that crude polyphenol fractions from C. sinensis, especially the WphF and EphF fractions, are good sources of functional food.

Yield Reductions in the $F_2$ and $F_3$ Generations of Highly Promising Varietal Crosses of Corn (유망시되는 옥수수 품종간교잡의 $F_2$$F_3$에 있어서의 수량감소)

  • Chea-Yu Cho;R.M. Lantican
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.14
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    • pp.123-131
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    • 1973
  • 1. In order to evaluate the performance of the $F_2$ and $F_3$ generations of $F_1$ varietal crosses which in past trials yielded better than or as high as the recommended double-cross hybrids, eleven yellow and five white-endosperm $F_1$ varietal crosses, their $F_2$ and $F_3$ generations, and the parental open-pollinated varieties together with the standard double-cross hybrids were tested in performance trials in the 1963 wet and 1963-64 dry seasons. The former trials, however, failed due to a strong typhoon that damaged the crop. 2. Net hybrid vigor was highly manifested in grain yield in the $F_1$ varietal crosses, which on the average was 39.9 per cent of the mid-parent yields. Reduction in heterosis was 27.2 per cent in the $F_2$and 30.3 per cent in the $F_3$ generation, respectively. 3. A fairly high degree of reduction in yield occurred in the $F_2$ and $F_3$ generation. On the average, the $F_2$ generation decreased by 17.6 per cent and the $F_3$ by 20.7 per cent. The losses in two generations were exhibited in two levels; four crosses decreased by 10.9 per cent and twelve combinations by 22.0 per cent. The advanced generations of one yellow cross, Cuban Yellow Flint ${\times}$ Hawaiian Flinty Dent, and three white flint crosses, Bicol White Flint ${\times}$ Eto Blanco, College White Flint ${\times}$ Eto Blanco and Bicol White Flint ${\times}$ Nariono 330b, yielded as high as Philippine Hybrid No.1 and Philippine Hybrid No.4, respectively. 4. No significant differences in yield were obtained between the $F_2$ and $F_3$ populations, showing that genetic equilibrium was reached in $F_2$, as may be expected in view of the Hardy-Weinberg law on panmixis. 5. As in past trials, Hawaiian Flinty Dent, a variety, yielded as high as Philippine Hybrid No. 1.

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On the Stability of a Higher Functional Equation in Banach Algebras

  • Jung, Yong-Soo
    • Kyungpook Mathematical Journal
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    • v.59 no.4
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    • pp.689-702
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    • 2019
  • Let 𝓐 and 𝓑 be real (or complex) algebras. We investigate the stability of a sequence F = {f0, f1, ⋯, fn, ⋯ } of mappings from 𝓐 into 𝓑 satisfying the higher functional equation: $$f_n(x+y+zw)=f_n(x)+f_n(y)+\;{\normalsize\sum\limits_{\tiny{i+j=n \atop i{\leq}j}}}\;[f_i(z)f_j(w)+c_{ij}f_i(w)f_j(z)]$$ for each n = 0, 1, ⋯ and all x, y, z, w ∈ 𝓐, where $$c_{ij}=\left\{1{\text{ if }}i{\neq}j,\\0{\text{ if }}i=j.\right.$$.

Studies on AlF3-(Mg+Sr+Ba)F2-P2O5 Glasses II. Effect of MgF2 Contents (AlF3-(Mg+Sr+Ba)F2-P2O5계 유리에 관한 연구 제2보 : MgF2의 영향)

  • 김정은;이종근
    • Journal of the Korean Ceramic Society
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    • v.24 no.3
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    • pp.277-281
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    • 1987
  • The various contents of MgF2 from 0 to 12.5wt% are studied in the AlF3-(Mg+Sr+Ba)F2-P2O5 system for the effects of various properties in glasses and the atmosphere of melting was controlled by N2 and Ar gas respectively. Density, refractive index, infrared transmission, thermal conductivity and thermal expansion coefficient of glasses are determined. Density, refractive index and thermal conductivity are decreased, micro-hardness and thermal expansion coefficient are increased according to the increasing of MgF2 contents. Infrared transmittance decreases with increasing the MgF2 contents and it slightly dropped by air than N2 and Ar atmosphere. Other properties are not influenced by atmosphere control.

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HEIGHT BOUND AND PREPERIODIC POINTS FOR JOINTLY REGULAR FAMILIES OF RATIONAL MAPS

  • Lee, Chong-Gyu
    • Journal of the Korean Mathematical Society
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    • v.48 no.6
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    • pp.1171-1187
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    • 2011
  • Silverman [14] proved a height inequality for a jointly regular family of rational maps and the author [10] improved it for a jointly regular pair. In this paper, we provide the same improvement for a jointly regular family: let h : ${\mathbb{P}}_{\mathbb{Q}}^n{\rightarrow}{{\mathbb{R}}$ be the logarithmic absolute height on the projective space, let r(f) be the D-ratio of a rational map f which is de ned in [10] and let {$f_1,{\ldots},f_k|f_l:\mathbb{A}^n{\rightarrow}\mathbb{A}^n$} bbe finite set of polynomial maps which is defined over a number field K. If the intersection of the indeterminacy loci of $f_1,{\ldots},f_k$ is empty, then there is a constant C such that $ \sum\limits_{l=1}^k\frac{1}{def\;f_\iota}h(f_\iota(P))>(1+\frac{1}{r})f(P)-C$ for all $P{\in}\mathbb{A}^n$ where r= $max_{\iota=1},{\ldots},k(r(f_l))$.

APPROXIMATELY QUINTIC MAPPINGS IN NON-ARCHIMEDEAN 2-NORMED SPACES BY FIXED POINT THEOREM

  • KIM, CHANG IL;JUNG, KAP HUN
    • Journal of applied mathematics & informatics
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    • v.33 no.3_4
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    • pp.435-445
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    • 2015
  • In this paper, using the fixed point method, we investigate the generalized Hyers-Ulam stability of the system of quintic functional equation $f(x_1+x_2,y)+f(x_1-x_2,y)=2f(x_1,y)+2f(x_2,y)\;f(x,2_{y1}+y_2)+f(x,2_{y1}-y_2)=f(x,y_1-2_{y2})+f(x,y_1+y_2)\;-f(x,y_1-y_2)+15f(x,y_1)+6f(x,y_2)$ in non-Archimedean 2-Banach spaces.

Polynomials satisfying f(x-a)f(x)+c over finite fields

  • Park, Hong-Goo
    • Bulletin of the Korean Mathematical Society
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    • v.29 no.2
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    • pp.277-283
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    • 1992
  • Let GF(q) be a finite field with q elements where q=p$^{n}$ for a prime number p and a positive integer n. Consider an arbitrary function .phi. from GF(q) into GF(q). By using the Largrange's Interpolation formula for the given function .phi., .phi. can be represented by a polynomial which is congruent (mod x$^{q}$ -x) to a unique polynomial over GF(q) with the degree < q. In [3], Wells characterized all polynomial over a finite field which commute with translations. Mullen [2] generalized the characterization to linear polynomials over the finite fields, i.e., he characterized all polynomials f(x) over GF(q) for which deg(f) < q and f(bx+a)=b.f(x) + a for fixed elements a and b of GF(q) with a.neq.0. From those papers, a natural question (though difficult to answer to ask is: what are the explicit form of f(x) with zero terms\ulcorner In this paper we obtain the exact form (together with zero terms) of a polynomial f(x) over GF(q) for which satisfies deg(f) < p$^{2}$ and (1) f(x+a)=f(x)+c for the fixed nonzero elements a and c in GF(q).

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Classification of Transmission Loss for Steel Panel and Extrusion Concrete Panel (건축용 철강제 벽판과 압출 성형 콘크리트 패널의 차음성능 구분)

  • 장길수;이태강;송민정;김선우
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.864-869
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    • 2003
  • KS F 2808 was revised in 2000 and KS F 2862-1 was newly established in 2001. Thus Related Korean Industrial Standard such as KS F 4724, KS F 4735, KS F 4736 should be revised according to KS F 2808 and KS F 28612-1. This study aims to elicit the new rating numbers such as R$\sub$w/, R$\sub$w/+C, R$\sub$w/+C$\sub$tr/, L$\sub$m/ defined in KS F 2862-1 instead of exiting rating number; transmission loss of 500Hz.

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Further Results about the Normal Family of Meromorphic Functions and Shared Sets

  • Qi, Jianming;Zhang, Guowei;Zhou, Linlin
    • Kyungpook Mathematical Journal
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    • v.52 no.1
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    • pp.39-47
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    • 2012
  • Let $\mathcal{F}$ be a family of meromorphic functions in a domain D, and let $k$, $n({\geq}2)$ be two positive integers, and let $S=\{a_1,a_2,{\ldots},a_n\}$, where $a_1$, $a_2$, ${\ldots}$, $a_n$ are distinct finite complex numbers. If for each $f{\in}\mathcal{F}$, all zeros of $f$ have multiplicity at least $k+1$, $f$ and $G(f)$ share the set $S$ in $D$, where $G(f)=P(f^{(k)})+H(f)$ is a differential polynomial of $f$, then$\mathcal{F}$ is normal in $D$.