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321.
Nobuko Mibu Hatsumi Aki Hirohito Ikeda Ai Saito Wataru Uchida Kazumi Yokomizo Jianrong Zhou Takeshi Miyata Kunihiro Sumoto 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1015-1018
Carbohydrate recognition of some bioactive symmetrical tripodal receptor type tris(2-aminoethyl)amine (TAEA) derivatives was investigated. In calorimetric experiments, the highest binding constant (Ka) of compound C (C35H49N5O4S) with methyl α-d-mannopyranoside was Ka = 858 M?1 with 1:1 stoichiometry. Formation of hydrogen bonds in binding between symmetrical tripodal receptor type compound C and sugars was suggested by the large negative values of ?H° (=?34 to ?511 kJ mol?1). In a comparison of each set of α- and β-anomers of some monosaccharides (methyl α/β-d-galactopyranoside, methyl α/β-d-glucopyranoside, and methyl α/β-l-fucopyranoside), compound C showed that the binding constant of β-anomer was larger than that of the corresponding α-anomer, indicating higher β-anomer selectivity. The calculated energy-minimized structure of the complex of compound C with guest methyl α-d-mannopyranoside is also presented. The experimental results obtained from this work indicated that symmetrical tripodal receptor type TAEA derivative C has a lectin-like carbohydrate recognition property. 相似文献
322.
QSNPlite, a software system for quantitative analysis of SNPs based on capillary array SSCP analysis
Tahira T Okazaki Y Miura K Yoshinaga A Masumoto K Higasa K Kukita Y Hayashi K 《Electrophoresis》2006,27(19):3869-3878
We present a newly developed software called "QSNPlite" that comprehensively interprets the data of SSCP and sequencing analyses obtained from capillary array electrophoresis systems used in the quantitative characterization of SNPs. QSNPlite assists in the genotyping of individuals with SNPs and in estimating the allele frequencies of SNPs using pooled DNA. We show that this estimation is accurate (mean absolute error, 1.4%) by comparing the results of the pooled analysis using QSNPlite with the true frequencies based on the allele counting after performing individual genotypings. The QSNPlite program runs on Windows XP and can be used to determine the allele frequencies of SNPs among a large number of individuals, such as in association studies of disease-responsible genes using the candidate gene approach. 相似文献
323.
Matrix certified reference materials for environmental monitoring from the National Metrology Institute of Japan (NMIJ) 总被引:2,自引:0,他引:2
Takashi Yarita Akiko Takatsu Kazumi Inagaki Masahiko Numata Koichi Chiba Kensaku Okamoto 《Accreditation and quality assurance》2007,12(3-4):156-160
Matrix certified reference materials (CRMs) are playing an increasingly important role in environmental monitoring in Japan.
The National Metrology Institute of Japan (NMIJ)/National Institute of Advanced Industrial Science and Technology (AIST) has
been developing matrix CRMs for environmental monitoring since 2001, and has issued nine kinds of CRMs as NMIJ CRMs. The development
of the CRMs was conducted in NMIJ in cooperation with candidate material producers. The isotope dilution mass spectrometry
(IDMS) was principally adopted to give reliable certified values. Meanwhile, two or more analytical methods, whose levels
of accuracy were well evaluated, were applied to avoid any possible analytical bias. Two typical certification processes,
the certification of river water CRMs for trace element analysis and that of marine sediment CRMs for PCB and organochlorine
pesticide analysis, are outlined as examples.
Presented at -- “BERM-10” -- April 2006, Charleston, SC, USA. 相似文献
324.
Orita A Nakano T An DL Tanikawa K Wakamatsu K Otera J 《Journal of the American Chemical Society》2004,126(33):10389-10396
Pyridine-containing arylene ethynylene strands were connected to the 2- and 2'-positions of (R)- and (S)-1,1'-binaphthyl templates. The arylene ethynylene moieties underwent intramolecular coordination with Ag(I) or Cu(I) ion to afford enantiopure double helicates. The double-helical structure was elucidated on the basis of circular dichroic (CD) spectra. The importance of intramolecular complexation of the double strands for the helicate formation was confirmed by comparison with a ligand bearing a single strand. Connection of the strands through an ether linkage enabled a sorting out of the Cotton effect induced by double-helical arylene ethynylene moieties. The CD exciton chirality method unambiguously proved that the termini of the strands approach each other upon complexation and that the sense of the induced helicity is the same as predicted by molecular modeling. 相似文献
325.
Itoh N Inagaki K Narukawa T Aoyagi Y Narushima I Koguchi M Numata M 《Analytical and bioanalytical chemistry》2011,401(9):2909-2918
The National Metrology Institute of Japan has issued a certified reference material of tunnel dust for polycyclic aromatic
hydrocarbons (PAHs) and toxic element analyses. PAH certification was performed using isotope dilution mass spectrometry with
deuterium-labeled PAHs as internal standards. Three extraction techniques (microwave-assisted extraction with toluene/methanol,
Soxhlet extraction with toluene, and pressurized liquid extraction with toluene) were used, and the extracts were measured
by gas chromatography/mass spectrometry with two different columns. For values of PAHs, 11 PAHs are provided as certified
values between 0.294 and 20.3 mg/kg, and five PAHs are provided as information values. Certified values of five toxic elements
(Cr, Ni, Pb, Mn, and Cd) obtained from microwave-assisted digestions and a combination of measurement techniques are also
provided between 43.4 and 10.71 × 103 mg/kg. 相似文献
326.
Sudo Y Iwamoto M Shimono K Kamo N 《Journal of photochemistry and photobiology. B, Biology》2002,67(3):171-176
Pharaonis phoborhodopsin (ppR or pharaonis sensory rhodopsin II) is a receptor of the negative phototaxis of Natronobacterium pharaonis and forms a complex with its transducer pHtrII in membranes. Flash-photolyis of a D75N mutant did not yield the M-intermediate, but an O-like intermediate is observed in a ms time range. We examined the interaction between the D75N of ppR and t-Htr (truncated pHtrII). These formed a complex in the presence of 0.1% n-dodecyl-beta-maltoside, and the association accelerated the decay of the O of D75N from 15 to 56 s(-1). From the decay time constants under varying ratios of D75N and t-Htr, n, the molar ratio of D75N/t-Htr in the complex, and K(D), the dissociation constant, were estimated. The value of n was unity and K(D) was estimated to 146 nM. This K(D) value can be considered to be the association between the photo-intermediate and t-Htr, which is deduced by the method of estimation. Previously we (Photochem. Photobiol. 74 (2001) 489) reported a K(D) of 15 microM for the interaction between the wild-type and t-Htr by means of the change in M-decay rates. Therefore, this value should be the K(D) value for the interaction between M of the wild-type and t-Htr. 相似文献
327.
Kogen H Toda N Tago K Marumoto S Takami K Ori M Yamada N Koyama K Naruto S Abe K Yamazaki R Hara T Aoyagi A Abe Y Kaneko T 《Organic letters》2002,4(20):3359-3362
Highly efficient acetylcholinesterase (AChE) and serotonin transporter (SERT) dual inhibitors, (S)-4 and (R)-13 were designed and synthesized on the basis of the hypothetical model of AChE active site. Both compounds showed potent inhibitory activities against AChE and SERT. [structure: see text] 相似文献
328.
Abstract Okinaga et al.1 have recently reported a novel trisaccharide obtained from the acrosome reaction-inducing substance (ARIS) of the starfish Asterias amurensis. The ARIS is essential for triggering the acrosome reaction in homologous spermatozoa, and the biological activity is due to the sugar moiety. The trisaccharide, composed of xylose (Xyl), galactose (Gal), and fucose (Fuc), and proposed to have a sequence of Xyll→3Gall→3 or 4[4 or 3-(So3 ?)]Fuc, was deduced to be one of the major structural units constructing the side chain of the high molecular carbohydrate portion of the ARIS. The sequence differs from similar oligosaccharides, found in hemicellulose2 and composed of d-xylose, d-galactose, and l-fucose. The ARIS contains a unique saccharide chain having sulfated l-fucose as an internal residue. This unique structure prompted us to synthesize the trisaccharide as well as to reveal the anomeric configuration of Xyl and Gal moieties and the sulfated position of Fuc residue. 相似文献
329.
Yoji Koike Sei-ichi Tanuma Hiroyoshi Suematsu Kohei Higuchi 《Journal of Physics and Chemistry of Solids》1980,41(10):1111-1118
Superconducting properties of pseudo-single crystals of C8K were investigated by low frequency a.c. magnetic susceptibility and electrical resistivity measurements. The measured values of Tc were between 128 and 198 mK for 13 samples. Measurements of the superconducting transition in a magnetic field revealed a remarkable anisotropy, such that if θ is defined as the angle between the applied magnetic field and the layer plane, type II superconductivity was observed for 0° ≦ ∣ θ ∣ ? 25° and type I superconductivity for 25° ? ∣ θ ∣≦ 90°. The angular dependences of Hc2 and Hc3 were fairly well-explained by the effective mass model. 相似文献
330.
Triplet superconductors such as Sr2RuO4 and NaxCoO2·yH2O are now found to be p-wave (px±ipy) or f-wave ((px±ipy)coscpz) superconductors. In conventional singlet superconductors, vortices are quantized because phase of order parameter must rotate by 2π around a vortex. But triplet superconductors have a degree of freedom of spin, which is described by d-vector. The d-vector and phase can rotate by π around a vortex, separately. Therefore appearance of HQVs is predicted. Theoretically, it is found that a pair of HQVs is more stable than a singly quantized vortex, for several parameter regions.In this study, in order to investigate quasi-particle bound states around two vortices in s-wave superconductors, we have developed a new numerical method to solve the BdG equation for two vortices state, using Mathieu functions. We confirmed the validity of this method for two vortices state and applied it in case of a pair of vortices. And we solved it. 相似文献