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161.
Ken’ichiro Tanaka Tomoaki Okayama Takayasu Matsuo Masaaki Sugihara 《Numerische Mathematik》2013,125(3):511-543
In this paper, the theoretical convergence rate of the trapezoidal rule combined with the double-exponential (DE) transformation is given for a class of functions for which the single-exponential (SE) transformation is suitable. It is well known that the DE transformation enables the rule to achieve a much higher rate of convergence than the SE transformation, and the convergence rate has been analyzed and justified theoretically under a proper assumption. Here, it should be emphasized that the assumption is more severe than the one for the SE transformation, and there actually exist some examples such that the trapezoidal rule with the SE transformation achieves its usual rate, whereas the rule with DE does not. Such cases have been observed numerically, but no theoretical analysis has been given thus far. This paper reveals the theoretical rate of convergence in such cases, and it turns out that the DE’s rate is almost the same as, but slightly lower than that of the SE. By using the analysis technique developed here, the theoretical convergence rate of the Sinc approximation with the DE transformation is also given for a class of functions for which the SE transformation is suitable. The result is quite similar to above; the convergence rate in the DE case is slightly lower than in the SE case. Numerical examples which support those two theoretical results are also given. 相似文献
162.
This paper considers the pricing of contingent claims using an approach developed and used in insurance pricing. The approach is of interest and significance because of the increased integration of insurance and financial markets and also because insurance-related risks are trading in financial markets as a result of securitization and new contracts on futures exchanges. This approach uses probability distortion functions as the dual of the utility functions used in financial theory. The pricing formula is the same as the Black-Scholes formula for contingent claims when the underlying asset price is log-normal. The paper compares the probability distortion function approach with that based on financial theory. The theory underlying the approaches is set out and limitations on the use of the insurance-based approach are illustrated. The probability distortion approach is extended to the pricing of contingent claims for more general assumptions than those used for Black-Scholes option pricing. 相似文献
163.
Soumaya Touzani Hamada Imtara Shankar Katekhaye Hamza Mechchate Hayat Ouassou Ali S. Alqahtani Omar M. Noman Fahd A. Nasr Hugo Fearnley James Fearnley Anant Paradkar Ilham ElArabi Badiaa Lyoussi 《Molecules (Basel, Switzerland)》2021,26(15)
The biological activities of propolis samples are the result of many bioactive compounds present in the propolis. The aim of the present study was to determine the various chemical compounds of some selected propolis samples collected from Palestine and Morocco by the High-Performance Liquid Chromatography–Photodiode Array Detection (HPLC-PDA) method, as well as the antioxidant and antibacterial activities of this bee product. The chemical analysis of propolis samples by HPLC-PDA shows the cinnamic acid content in the Palestinian sample is higher compared to that in Moroccan propolis. The results of antioxidant activity demonstrated an important free radical scavenging activity (2,2-Diphenyl-1-picrylhydrazyl (DPPH); 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and reducing power assays) with EC50 values ranging between 0.02 ± 0.001 and 0.14 ± 0.01 mg/mL. Additionally, all tested propolis samples possessed a moderate antibacterial activity against bacterial strains. Notably, Minimum Inhibitory Concentrations (MICs) values ranged from 0.31 to 2.50 mg/mL for Gram-negative bacterial strains and from 0.09 to 0.125 mg/mL for Gram-positive bacterial strains. The S2 sample from Morocco and the S4 sample from Palestine had the highest content of polyphenol level. Thus, the strong antioxidant and antibacterial properties were apparently due to the high total phenolic and flavone/flavonol contents in the samples. As a conclusion, the activities of propolis samples collected from both countries are similar, while the cinnamic acid in the Palestinian samples was more than that of the Moroccan samples. 相似文献
164.
Tomoaki Miura 《Molecular physics》2020,118(6)
Since 1970s, magnetic field effects (MFEs) on photogenerated radical pairs have been the centre of focus in the field of spin chemistry. The MFE attributes to quantum mechanical interconversion between the singlet and triplet radical pair states and subsequent spin-selective recombination reactions. In this New View article, the author picks up two hot topics studied during the last two decades, which are (i) so-called low field effect (LFE) and (ii) 2J-resonance MFE on fixed distance donor–acceptor linked molecules. In both of the topics, quantum mechanical explanations are given referring to recent reports, and some novel calculations have been carried out for bridging theoretical and experimental data for long-lived radical pairs. For the first topic, time domain calculations of coherent state mixing have been carried out for elucidation of hyperfine (HF) structure dependence of the LFE. For the second topic, Monte Carlo simulations of the torsional motion of polyaromatic linker unit have been carried out for the demonstration of fast decoherence in such rigid molecules. From these considerations, future possibilities of MFE studies on photo-functional materials and biomolecules have been indicated. 相似文献
165.
Thermo‐triggered Release of CRISPR‐Cas9 System by Lipid‐Encapsulated Gold Nanoparticles for Tumor Therapy 下载免费PDF全文
Dr. Peng Wang Dr. Lingmin Zhang Prof. Wenfu Zheng Dr. Liman Cong Zhaorong Guo Yangzhouyun Xie Le Wang Rongbing Tang Qiang Feng Prof. Yoh Hamada Prof. Kohsuke Gonda Prof. Zhijian Hu Prof. Xiaochun Wu Prof. Xingyu Jiang 《Angewandte Chemie (International ed. in English)》2018,57(6):1491-1496
CRISPR/Cas9 system is a powerful toolbox for gene editing. However, the low delivery efficiency is still a big hurdle impeding its applications. Herein, we report a strategy to deliver Cas9‐sgPlk‐1 plasmids (CP) by a multifunctional vehicle for tumor therapy. We condensed CPs on TAT peptide‐modified Au nanoparticles (AuNPs/CP, ACP) via electrostatic interactions, and coated lipids (DOTAP, DOPE, cholesterol, PEG2000‐DSPE) on the ACP to form lipid‐encapsulated, AuNPs‐condensed CP (LACP). LACP can enter tumor cells and release CP into the cytosol by laser‐triggered thermo‐effects of the AuNPs; the CP can enter nuclei by TAT guidance, enabling effective knock‐outs of target gene (Plk‐1) of tumor (melanoma) and inhibition of the tumor both in vitro and in vivo. This AuNPs‐condensed, lipid‐encapsulated, and laser‐controlled delivery system provides a versatile method for high efficiency CRISPR/Cas9 delivery and targeted gene editing for treatment of a wide spectrum of diseases. 相似文献
166.
Hidetaka Hamada 《Journal of Geometric Analysis》1998,8(3):441-446
The purpose of this paper is to prove that every proper holomorphic self-mapping of a Reinhardt domain Ω in
C
n
which is a generalization of a complex ellipsoid is biholomorphic. The main novelty of our result is that Ω is a domain in
C
n
such that it is allowed to have a boundary point at which the Levi determinant has infinite order of vanishing. 相似文献
167.
Fumio Hamada G. William Orr Hongming Zhang Jerry L. Atwood 《Journal of chemical crystallography》1993,23(8):681-684
The title compound has been prepared by the addition of bromocalix[4]arene methyl ether to CuCN in N-methylpyrrolidone. The crystals belong to the monoclinic space groupP21/n witha=13.591(3),b=24.778(5),c=11.057(3)Å,=93.58(2)°, andD
c=1.09 g cm–3 forZ=4. Refinement based on 1118 observed reflections led to a finalR value of 0.085. The molecule exhibits the partial cone conformation. 相似文献
168.
Hamasaki A Yago T Takamasu T Kido G Wakasa M 《The journal of physical chemistry. B》2008,112(11):3375-3379
The magnetic field effects (MFEs) on photoinduced hydrogen abstraction reactions between benzophenone and thiophenol in an ionic liquid, N,N,N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl) imide (TMPA TFSI), were studied by a nanosecond laser flash photolysis technique under ultrahigh fields of up to 28 T. Extremely large and anomalous stepwise MFEs were observed for the first time. The escape yield of benzophenone ketyl radical decreased with increasing magnetic field strength (B) at 0 T相似文献
169.
K. Tanoi H. Matsue H. Iikura T. Saito Y. Hayashi Y. Hamada H. Nishiyama N. I. Kobayashi T. M. Nakanishi 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):375-379
We carried out instrumental neutron activation analysis (INAA) as well as k
0-based prompt gamma-ray analysis (k
0-PGA) to measure the amount of the elements in onions and studied whether the onions collected from different sites can be
categorized based on the elemental concentration profile. Six elements (Na, Mg, Cl, K, Ca, Mn) and 3 elements (B, S, Cl) were
measured by INAA and PGA in the onions grown in two districts, Hokkaido and Saga, in Japan, respectively. After principal
component analysis, it was found that Cl was an important element to feature the producing districts of onions. 相似文献
170.
The size and shape of the chiral cavity of a macrocyclic receptor were tuned by the alteration of the binaphthyl moiety to improve the chiral recognition/discrimination ability. For example, host 3 with the 3,5-bis(trifluoromethyl)phenyl group at the 3,3'-positions showed improved enantioselectivity for small molecules such as 2-chloropropionic acid and methyl lactate as evaluated by the binding constants. This host 3 also had an excellent ability as an NMR chiral solvating agent. 相似文献