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Fungal Diversity and Plant Growth Promotion of Endophytic Fungi from Six Halophytes in Suncheon Bay

  • You, Young-Hyun;Yoon, Hyeokjun;Kang, Sang-Mo;Shin, Jae-Ho;Choo, Yeon-Sik;Lee, In-Jung;Lee, Jin-Man;Kim, Jong-Guk
    • Journal of Microbiology and Biotechnology
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    • v.22 no.11
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    • pp.1549-1556
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    • 2012
  • Endophytic fungi were isolated from roots of six halophytes in Suncheon Bay. The endophytic fungi of 35 species isolated from halophytes were identified by internal transcribed spacer (ITS) containing the ITS1, 5.8s, and ITS2 regions. All fungal strains were analyzed to diversity at the genus level. Fungal culture filtrates (FCF) of endophytic fungi were treated to Waito-c rice (WR) seedling for plant growth-promoting verification. It was confirmed that fungal strain Sj-2-2 provided plant growth promotion (PGP) to WR seedling. Then, PGP of Suaeda japonica was confirmed by treating culture filtrate of Sj-2-2. As a result, it was verified that culture filtrate of Sj-2-2 had more advanced PGP than positive control when treated to S. japonica. The secondary metabolites involved in culture filtrate of Sj-2-2 were identified by HPLC and GC-MS SIM analysis. The presence of physiologically bioactive gibberellins (GAs) and other inactive GAs in culture filtrate of Sj-2-2 was detected. The molecular analysis of sequences of Sj-2-2 showed the similarity to Penicillium sp. of 99% homology. The PGP of Sj-2-2 as well as symbiosis between endophytic fungi and halophytes growing naturally in salt marsh was confirmed. Sj-2-2 was identified as a new fungal strain producing GAs by molecular analysis of sequences. Consequently, the Sj-2-2 fungal strain was named as Penicillium sp. Sj-2-2. In this study, the diversity of endophytic fungi isolated from roots of halophytes in salt marsh and the PGP of a new gibberellin-producing fungal strain were confirmed.

Different Mechanisms for the Activation of Vascular Smooth Muscle by Norepinephrine and Depolarization (혈관 평활근의 수축기전에 관한 연구)

  • Hong, Yong-Woo;Ko, Kwang-Wook;Kim, Ki-Whan
    • The Korean Journal of Physiology
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    • v.21 no.2
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    • pp.191-200
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    • 1987
  • The activation mechanism of the sustained contractions induced by norepinephrine and K-depolarization was studied in renal vascular muscle. Helical strips of arterial muscle were prepared from rabbit renal arteries. All experiments were performed in Tris-buffered Tyrode solution which was aerated with 100% $O_2$ and kept at $35^{\circ}C$. Renal arterial muscles developed a contracture rapidly when exposed to a 40 mM K-Tyrode solution. In the absence of external $Ca^{2+}$, however, no K-contracture appeared. The contracture induced by K-depolarization was abolished by the treatment with $Ca^{2+}-antagonist\;(verapamil)$ or lanthanum $(La^{3+})$. From these results, it is obvious that K-contracture of renal arterial strip required $Ca^{2+}$ in the medium and this contracture was developed by the increased $Ca^{2+}-influx$ due to K-depolarization. Noradrenaline (5 mg/l) induced also a similar sustained contraction rapidly in all strips. Even on the K-contracture and in $Ca^{2+}-free$ Tyrode solution and also in the Tyrode solution pretreated with verapamil or $La^{3+}$, noradrenaline produced a contraction. However, the contraction in $Ca^{2+}-free$ Tyrode solution was not sustained and decreased gradually. The amplitude of noradrenaline-induced contracture was dependent on external $Ca^{2+}$; The contracture increased dose-dependently, but over 3 mM $Ca^{2+}$, decreased. The results of this experiment suggest that K-contracture was developed by an increased $Ca^{2+}-influx$ due to membrane depolarization, while noradrenaline-induced contracture was developed by both transmembrane $Ca^{2+}-influx$ and the mobilizaiton of cellular $Ca^{2+}$

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Thermal Performance Assessment of Insulated door by experiment. (실측 실험을 통한 단열문의 열성능 평가)

  • Jang, Cheol-Yong;Kim, Chi-Hoon;Ahn, Byung-Lip;Hong, Won-Hwa
    • Journal of the Korean Solar Energy Society
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    • v.31 no.2
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    • pp.47-52
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    • 2011
  • Currently, Exterior wall's U-value about building envelope is 0.36 W/$m^2K$(Central Region), but window's one is 2.1 W/$m^2K$ according to air gap of glazing, filling gas, coating and type of windows. The door"s one is 1.6~5.5 W/$m^2{\cdot}K$ depending on material and configuration of door. As such, energy loss per unit of door is considerably larger like windows. The door for the recognition was relatively low because energy loss through the door is relatively small compared to window area. In this paper, thermal performance was analyzed through simulation targeting the door which has thermal break that can improve the insulation performance and doesn't have one. As a results of simulations, case1 was calculated as the average of 1.63 w/m2k and case 2 was calculated as the average of 4.14 w/m2k. The thermal performance of door depends on the type and condition of insulations. As a results of final simulations, Case1 was calculated as 1.06 w/m2k and Case2 was calculated as 1.27 w/m2k. As a results of the experiments, thermal performance of case 1 was measured as 1.28 w/m2k. Error between experiments and simulations is considered problems encountered when creating the samples. The effect of door frame on the overall thermal performance is slight because it's a small proportion of the door frame.

Changes in the Quality of Peaches (Prunus persica L. Batsch) Treated by UV-C Irradiation during Storage (Ultraviolet-C 조사에 의한 복숭아의 저장 중 품질변화)

  • Jang, Joo-Hee;Park, Jae-Hee;Ban, Ki-Eun;Lee, Kyung-Haeng
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.12
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    • pp.1798-1804
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    • 2012
  • To prolong the shelf-life of domestic peaches, samples were treated with UV-C (0~10.0 $kJ/m^2$) and the spoiling rate and changes in physico-chemical and sensory properties were investigated. No spoiled peaches were observed within the first four days of storage in the control and 2.5 $kJ/m^2$ UV-C treatment groups. However, spoilage was observed in these groups on day six, and 29.17% and 25.0% of the samples showed spoilage on 10 day, respectively. Moreover, samples treated with greater than 5.0 $kJ/m^2$ of UV-C showed a higher percentage (41.67% or higher) of spoilage than those of the control or 2.5 $kJ/m^2$ UV-C treatment groups on 10 day. Additionally, weight changes in the peaches were the lower in the control group and 2.5 $kJ/m^2$ UV-C treatment group than in those treated with 5.0 $kJ/m^2$ of UV-C treatment or higher during 10 days of storage. There was no difference in pH among treatments, regardless of storage time. The hardness of the samples was not changed immediately after UV-C treatment, but that of samples treated with 5.0~10.0 $kJ/m^2$ of UV-C decreased rapidly after four days, when compared to the control and 2.5 $kJ/m^2$ UV-C treatment groups. No significant changes in the lightness and redness of the samples were observed in response to UV-C treatment, however, UV-C treatment led to a slight decrease in the yellowness of the samples. The initial taste, flavor, color, texture, and overall acceptance did not differ among control and UV-C treatments. The sensory score of the samples was the highest after 2 and 4 days of storage, while it decreased thereafter. In general, samples in the control and the 2.5 $kJ/m^2$ UV-C treatment groups showed higher sensory quality than those treated with UV-C at 5.0 $kJ/m^2$ or higher.

TiO2 Branched Nanostructure Anode Material Prepared by Seeding Method for High-performance Lithium Ion Batteries

  • Han, Biao;Kim, Si-Jin;Hwang, Bo-Mi;Hwang, Eui-Tak;Park, Han Chul;Koh, Mun-Hyun;Park, Kyung-Won
    • Journal of the Korean Electrochemical Society
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    • v.16 no.2
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    • pp.81-84
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    • 2013
  • We demonstrate rutile $TiO_2$ branched nanostructure ($TiO_2$-BN) electrodes synthesized by seeding method for enhanced lithium intercalation properties. The morphology and crystalline nature of the $TiO_2$-BN were clearly observed by field-emission transmission electron microscopy and fast Fourier transform pattern. The $TiO_2$-BN electrodes showed excellent capacity and high rate performance. The improved lithium-ion intercalation properties of the $TiO_2$- BN may be attributed to relatively large specific surface area and short transport distance of the branched nanostructure.

Microwave Synthesis of Chiral N-Benzyl-2-methyl-2H-benzo[b][1,4]oxazin/thiazin-3(4H)-ones via Smiles Rearrangement and their Biological Evaluation

  • Meng, Li-Juan;Zuo, Hua;Vijaykumar, B.V.D.;Dupati, Gautam;Choi, Kyung-Min;Jang, Kiwan;Yoon, Yong-Jin;Shin, Dong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.585-589
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    • 2013
  • Optically active N-benzyl-2-methyl-2H-benzo[b][1,4]oxazin-3(4H)-ones and N-benzyl-2-methyl-2H-benzo[b][1,4]thiazin-3(4H)-ones with potential synthetic and pharmacological interest were prepared via Smiles rearrangement in conventional as well as microwave irradiation conditions in one-pot from inexpensive (S)-2-chloropropionic acid. Most of the compounds displayed good inhibition against Gram positive bacteria and fungi in the antibiotic test.

ON THE γ-TH HYPER-KLOOSTERMAN SUMS AND A PROBLEM OF D. H. LEHMER

  • Tianping, Zhang;Xifeng, Xue
    • Journal of the Korean Mathematical Society
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    • v.46 no.4
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    • pp.733-746
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    • 2009
  • For any integer k $\geq$ 2, let P(c, k + 1;q) be the number of all k+1-tuples with positive integer coordinates ($a_1,a_2,...,a_{k+1}$) such that $1{\leq}a_i{\leq}q$, ($a_i,q$) = 1, $a_1a_2...a_{k+1}{\equiv}$ c (mod q) and 2 $\nmid$ ($a_1+a_2+...+a_{k+1}$), and E(c, k+1; q) = P(c, k+1;q) - $\frac{{\phi}^k(q)}{2}$. The main purpose of this paper is using the properties of Gauss sums, primitive characters and the mean value theorems of Dirichlet L-functions to study the hybrid mean value of the r-th hyper-Kloosterman sums Kl(h,k+1,r;q) and E(c,k+1;q), and give an interesting mean value formula.

WEYL'S THEOREM AND TENSOR PRODUCT FOR OPERATORS SATISFYING T*k|T2|Tk≥T*k|T|2Tk

  • Kim, In-Hyoun
    • Journal of the Korean Mathematical Society
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    • v.47 no.2
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    • pp.351-361
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    • 2010
  • For a bounded linear operator T on a separable complex infinite dimensional Hilbert space $\mathcal{H}$, we say that T is a quasi-class (A, k) operator if $T^{*k}|T^2|T^k\;{\geq}\;T^{*k}|T|^2T^k$. In this paper we prove that if T is a quasi-class (A, k) operator and f is an analytic function on an open neighborhood of the spectrum of T, then f(T) satisfies Weyl's theorem. Also, we consider the tensor product for quasi-class (A, k) operators.

LIE IDEALS IN TRIDIAGONAL ALGEBRA ALG𝓛

  • Kang, Joo Ho
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.2
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    • pp.351-361
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    • 2015
  • We give examples of Lie ideals in a tridiagonal algebra $Alg\mathcal{L}_{\infty}$ and study some properties of Lie ideals in $Alg\mathcal{L}_{\infty}$. We also investigate relationships between Lie ideals in $Alg\mathcal{L}_{\infty}$. Let k be a fixed natural number. Let $\mathcal{A}$ be a linear manifold in $Alg\mathcal{L}_{\infty}$ such that $T_{(2k-1,2k)}=0$ for all $T{\in}\mathcal{A}$. Then $\mathcal{A}$ is a Lie ideal if and only if $T_{(2k-1,2k-1)}=T_{(2k,2k)}$ for all $T{\in}\mathcal{A}$.

Trends in standard of IEC 60947-2 for low voltage circuit breaker (IEC 60947-2 저압차단기 규격 동향)

  • Lee, Dong-Jun;Roh, Chang-Il;Kim, Ji-Hwan;Kim, Sun-Koo;Kim, Won-Man;Kim, Sun-Ho;Kim, Chul-Hwan
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.689-690
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    • 2008
  • IEC 60947-2는 산업용 저압차단기와 관련한 국제 규격이다. UL 규격을 사용하는 미국과 같이 자국의 규격을 사용하는 국가이외 에는 전 세계적으로 통용되는 규격으로서, 우리나라도 IEC 60947-2와 부합화를 한 K60947-2를 사용하고 있다. IEC 60947-2는 현재 Edition 4까지 개정되어 발행되었으며 해당 working group에서는 Edition 4의 amendment 1을 발행하기 위한 작업이 진행 중이다. 본 논문에서는 IEC 60947-2 working group에서 현재 진행되고 있는 amendment 내용 중 중요 이슈들에 대해 고찰하였으며, 향후 amendment 2에 대한 작업내용에 대한 소개를 하였다.

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