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361.
The present paper provides an experimental verification of amplitude death induced by a periodic time-varying delay-connection in a pair of double-scroll chaotic circuits. The connection is experimentally confirmed to enlarge the death region in a connection-parameter space, as compared with a well-known time-invariant delay-connection. The region observed in our circuit experiments agrees well with the analytical results. 相似文献
362.
Dynamic Kinetic Resolution Approach for the Asymmetric Synthesis of Tetrahydrobenzodiazepines Using Transfer Hydrogenation by Chiral Phosphoric Acid
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Kosaku Horiguchi Eri Yamamoto Dr. Kodai Saito Prof. Dr. Masahiro Yamanaka Prof. Dr. Takahiko Akiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8078-8083
Asymmetric synthesis of tetrahydrobenzodiazepines was achieved by transfer hydrogenation of dihydrobenzodiazepines with benzothiazoline having a hydrogen‐bonding donor substituent by means of a newly synthesized chiral phosphoric acid. This method was applicable to various racemic dihydrobenzodiazepines to give the corresponding products in good yields with excellent diastereoselectivities and enantioselectivities taking advantage of the dynamic kinetic resolution. Furthermore, the effect of bulky substituent at 3,3′‐position on the catalyst and hydrogen‐bonding donor substituent on benzothiazoline was fully elucidated by the theoretical study. 相似文献
363.
Frontispiece: Biomineralization‐Inspired Preparation of Zinc Hydroxide Carbonate/Polymer Hybrids and Their Conversion into Zinc Oxide Thin‐Film Photocatalysts
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364.
S‐((Phenylsulfonyl)difluoromethyl)thiophenium Salts: Carbon‐Selective Electrophilic Difluoromethylation of β‐Ketoesters, β‐Diketones,and Dicyanoalkylidenes
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Xin Wang Guokai Liu Dr. Xiu‐Hua Xu Naoyuki Shibata Etsuko Tokunaga Prof. Dr. Norio Shibata 《Angewandte Chemie (International ed. in English)》2014,53(7):1827-1831
S‐((Phenylsulfonyl)difluoromethyl)thiophenium salts were designed and prepared by a triflic acid catalyzed intramolecular cyclization of ortho‐ethynyl aryldifluoromethyl sulfanes. The thiophenium salts were found to be efficient as electrophilic difluoromehtylating reagents for introduction of a CF2H group to sp3‐hybridized carbon nucleophiles such as of β‐ketoesters and dicyanoalkylidenes. The (phenylsulfonyl)difluoromethyl group can be readily transformed into CF2H under mild reaction conditions. Enantioselective electrophilic difluoromethylation was also achieved in the presence of bis(cinchona) alkaloids. 相似文献
365.
Naoyuki Iida Masayuki Fujita Kohtaro Miyazawa Michimoto Kobayashi Seisuke Hattori 《Electrophoresis》2014,35(4):554-562
Protein phosphorylation is a major mechanism that regulates many basic cellular processes. Identification and characterization of substrates for a given protein kinase can lead to a better understanding of signal transduction pathways. However, it is still difficult to efficiently identify substrates for protein kinases. Here, we propose an integrated proteomic approach consisting of in vitro dephosphorylation and phosphorylation, phosphoprotein enrichment, and 2D‐DIGE. Phosphatase treatment significantly reduced the complexity of the phosphoproteome, which enabled us to efficiently identify the substrates. We employed p38 mitogen‐activated protein kinase (p38 MAP kinase) as a model kinase and identified 23 novel candidate substrates for this kinase. Seven selected candidates were phosphorylated by p38 MAP kinase in vitro and in p38 MAP kinase‐activated cells. This proteomic approach can be applied to any protein kinase, allowing global identification of novel substrates. 相似文献
366.
Y. Shindo M. Yoshida F. Narita K. Horiguchi 《Journal of the mechanics and physics of solids》2004,52(5):1109-1124
The effects of applied voltage on the electroelastic field concentrations ahead of electrodes in multilayer piezoelectric actuators were examined in a combined experimental and numerical investigation. Experiments were performed to measure the strain near internal and surface electrodes at various electrical loading conditions. The finite element method was also used to solve the coupled electro-elastic boundary value problem. The strain, stress and electric displacement concentrations were calculated and a non-linear behavior induced by localized polarization switching was discussed. A comparison of strain concentration was made between experiment and simulation. 相似文献
367.
A three-dimensional video-assisted stereoendoscopic system (3D video system) developed by the Shinko Optical Company, Ltd. (Tokyo, Japan), and referred to as the binocular vision by horizontal image shifting display method (BVHIS display method), has been developed to digitally process ordinary video signals obtained with a video camera connected to a direct videolaryngoscope. The three-dimensional video system provides the surgeon with stereoendoscopic video images and enhances the ability of the surgeon to perform delicate endoscopic procedures. The three-dimensional video-assisted stereoendoscopic laryngosurgical procedure and its underlying principles are described in this paper. A total of 12 patients with laryngeal lesions causing dysphonia underwent three-dimensional video-assisted stereoendoscopic laryngosurgery. Although the video image obtained with the BVHIS display method is only pseudo-three-dimensional, this method enables the surgeon to perceive both depth perception and realism. We describe a surgical procedure using this new visualizing technique and the underlying principles of the technique. Preoperative and postoperative evaluations of the patients' vocal functions are also described. This system is a useful tool for the treatment of laryngeal lesions causing dysphonia. 相似文献
368.
Lithium α-sulfinyl carbanion of 1-chloroethyl p-tolyl sulfoxide was reacted with 2-substituted cyclohexanones to afford adducts in good yields. The adducts were treated with LDA or t-BuMgCl to give lithium or magnesium alkoxides, which were treated with t-BuLi or i-PrMgCl to afford one-carbon ring-expanded 2,7-disubstituted cycloheptanones through β-oxido carbenoids. Interestingly, 2,3-disubstituted cycloheptanones were obtained in a trace amount or were not obtained at all. The enolate intermediates of this reaction were found to be able to get trapped with electrophiles to give 2,2,7-trisubstituted cycloheptanones in moderate to good yields. This method is very useful for the synthesis of 2,7-disubstituted cycloheptanones and 2,2,7-trisubstituted cycloheptanones from 2-substituted cyclohexanones in only two steps. 相似文献
369.
Naoyuki Taniguchi Jianguo Gu Motoko Takahashi Eiji Miyoshi 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(2):82
N-Acetylglucosaminyltransferase V (GnT-V), N-acetylglucosaminyltransferase III (GnT-III) and α1-6 fucosyltransferase (Fut8) catalyze reactions that form biologically important branching N-linked sugar chains in glycoproteins. The above three branching N-glycan sugar chains, β1-6 GlcNAc branching, bisecting GlcNAc and core fucose (α1-6 fucose), play major roles in cancer invasion and metastasis, the inhibition of cancer metastasis, and antibody-dependent cellular cytotoxicity (ADCC), growth and development, respectively. A functional glycomic approach identified the gain- and loss-of-functions of glycoproteins as the result of the aberrant glycosylation. A membrane-type metal dependent serine proteinase designated matriptase which contains β1-6 GlcNAc branching became resistant to auto-digestion and proteolysis by trypsin, and resulted in a constitutively active form which might be implicated in cancer invasion and metastasis. GnT-V also acts as an angiogenic factor without the mediation of functions as a glycosyltransferase. Recently, a GnT-V homologue, GnT-IX has been identified. This gene is expressed at relatively high levels in the brain and acts on N-glycans to form a unique branched structure, as well as O-mannosyl glycans. The addition of bisecting GlcNAc to various signaling molecules or adhesion molecules suppresses cancer metastasis. Fut8 knock-out mice, due to the lack of a core fucose (α1-6 fucose) in target glycoproteins, show disorders in growth and development. The presence of a bisecting GlcNAc or the absence of a core fucose in IgG molecules enhances ADCC activity for killing tumor cells by up to 10 to 100 fold and therefore is thought to have considerable use in antibody therapy against cancer. These data clearly indicate that gain- and loss-of-functions of target proteins for these glycosyltransferases are biologically important. 相似文献
370.