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991.
Nectrianolins A,B, and C,new metabolites produced by endophytic fungus Nectria pseudotrichia 120-1NP
Nanang Rudianto Ariefta Priska Kristiana Handojo Hadi Nurjanto Hiroyuki Momma Eunsang Kwon Tatsuya Ashitani Keitaro Tawaraya Tetsuya Murayama Takuya Koseki Hiroshi Furuno Narandulam Usukhbayar Ken-ichi Kimura Yoshihito Shiono 《Tetrahedron letters》2017,58(43):4082-4086
Two sesquiterpene-epoxycyclohexenone conjugates, nectrianolins A (1) and B (2), together with a sesquiterpene, nectrianolin C (3), were isolated from the brown rice culture of Nectria pseudotrichia 120-1NP, an endophytic fungus isolated from Gliricidia sepium. Their structures were determined on the basis of 1D-/2D-NMR spectroscopy and HRESIMS data analyses in combination with chemical means. Nectrianolins A–C (1–3) exhibited cytotoxic activity against both HL60 and HeLa cells. 相似文献
992.
Development of a Sensitive Bioluminogenic Probe for Imaging Highly Reactive Oxygen Species in Living Rats
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Dr. Mako Kamiya Prof. Eiji Kobayashi Dr. Toru Komatsu Dr. Tasuku Ueno Dr. Takuya Terai Dr. Kenjiro Hanaoka Prof. Tetsuo Nagano Prof. Yasuteru Urano 《Angewandte Chemie (International ed. in English)》2015,54(49):14768-14771
A sensitive bioluminogenic probe for highly reactive oxygen species (hROS), SO3H‐APL, was developed based on the concept of dual control of bioluminescence emission by means of bioluminescent enzyme‐induced electron transfer (BioLeT) and modulation of cell‐membrane permeability. This probe enables non‐invasive visualization of physiologically relevant amounts of hROS generated deep inside the body of living rats for the first time. It is expected to serve as a practical analytical tool for investigating a wide range of biological functions of hROS in vivo. The design concept should be applicable to other in vivo bioluminogenic probes. 相似文献
993.
Ruiji Li Dr. Takuya Nakashima Dr. Olivier Galangau Shunsuke Iijima Rui Kanazawa Prof. Tsuyoshi Kawai 《化学:亚洲杂志》2015,10(8):1725-1730
The high reactivity of 6π‐electrocyclization in polar solvents has remained one of the important challenges for diarylethenes because of the emergence of a twisted intramolecular charge transfer (TICT) state at the excited state in such polar media, which usually quenches the photocyclization reaction. Herein we report on the preparation and highly efficient photocyclization of 2,3‐diarylbenzo[b]thiophenes with nonsymmetric side‐aryl units in a polar solvent. While the dithiazolylbenzo[b]thiophene showed a suppressed quantum yield of 6π‐electrocyclization of 54 % in methanol, the replacement of a thiazole unit with a thiophene ring led to a photon‐quantitative 6π‐cyclization reaction. The nonsymmetrical modification into the side‐aryl units was considered to enhance the CH/π interactions between side‐aryl units to support a photoreactive conformation in methanol. The stabilization of the photochromic reactive conformation is expected to suppress the formation of the TICT state at the excited state, leading to highly efficient photoreactivity. 相似文献
994.
Takuya Tsuchiya 《Numerische Mathematik》1999,84(1):121-141
Summary. Finite element solutions of strongly nonlinear elliptic boundary value problems are considered. In this paper, using the
Kantorovich theorem, we show that, if the Fréchet derivative of the nonlinear operator defined by the boundary value problem
is an isomorphism at an exact solution, then there exists a locally unique finite element solution near the exact solution.
Moreover, several a priori error estimates are obtained.
Received March 2, 1998 / Published online September 7, 1999 相似文献
995.
Ryoichi Sato Yuta Kodera Md. Arshad Ali Takuya Kusaka Yasuyuki Nogami Robert H. Morelos-Zaragoza 《Entropy (Basel, Switzerland)》2021,23(9)
A cloud service to offer entropy has been paid much attention to. As one of the entropy sources, a physical random number generator is used as a true random number generator, relying on its irreproducibility. This paper focuses on a physical random number generator using a field-programmable gate array as an entropy source by employing ring oscillator circuits as a representative true random number generator. This paper investigates the effects of an XOR gate in the oscillation circuit by observing the output signal period. It aims to reveal the relationship between inputs and the output through the XOR gate in the target generator. The authors conduct two experiments to consider the relevance. It is confirmed that combining two ring oscillators with an XOR gate increases the complexity of the output cycle. In addition, verification using state transitions showed that the probability of the state transitions was evenly distributed by increasing the number of ring oscillator circuits. 相似文献
996.
Experiments of single water drop impact onto a plane water surface were carried out to investigate the effect of impingement
angle on the total mass of secondary drops produced during the collision. When the impingement angle (the angle between the
velocity vector of primary drop and the normal vector to water surface) was less than 50°, an increase in the impingement
angle led to a remarkable increase in the total mass of secondary drops; this could be attributed to a significant increase
in the secondary drop size. However, no secondary drop was observed within the experimental ranges tested when the impingement
angle exceeded 70°. 相似文献
997.
Takuya Yamano 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,18(1):103-106
We discuss how the thermodynamical Legendre transform structure can be retained not only for the arbitrary entropic form but
also for the arbitrary form of the energy constraints by following the discussion of Plastino and Plastino. The thermodynamic
relation between the expectation values and the conjugate Lagrange multipliers are seen to be universal. Furthermore, Gibbs'
fundamental equation is shown to be unaffected by the choice of the entropy and the definition of the mean values due to the
robustness of the Legendre transform structure.
Received 28 April 2000 and Received in final form 29 July 2000 相似文献
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