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101.
Yamada M Yao I Hayasaka T Ushijima M Matsuura M Takada H Shikata N Setou M Kwon AH Ito S 《Analytical and bioanalytical chemistry》2012,402(5):1921-1930
Direct tissue analysis using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) provides the means
for in situ molecular analysis of a wide variety of biomolecules. This technology—known as imaging mass spectrometry (IMS)—allows
the measurement of biomolecules in their native biological environments without the need for target-specific reagents such
as antibodies. In this study, we applied the IMS technique to formalin-fixed paraffin-embedded samples to identify a substance(s)
responsible for the intestinal obstruction caused by an unidentified foreign body. In advance of IMS analysis, some pretreatments
were applied. After the deparaffinization of sections, samples were subjected to enzyme digestion. The sections co-crystallized
with matrix were desorbed and ionized by a laser pulse with scanning. A combination of α-amylase digestion and the 2,5-dihydroxybenzoic
acid matrix gave the best mass spectrum. With the IMS Convolution software which we developed, we could automatically extract
meaningful signals from the IMS datasets. The representative peak values were m/z 1,013, 1,175, 1,337, 1,499, 1,661, 1,823, and 1,985. Thus, it was revealed that the material was polymer with a 162-Da unit
size, calculated from the even intervals. In comparison with the mass spectra of the histopathological specimen and authentic
materials, the main component coincided with amylopectin rather than amylose. Tandem MS analysis proved that the main components
were oligosaccharides. Finally, we confirmed the identification of amylopectin by staining with periodic acid-Schiff and iodine.
These results for the first time show the advantages of MALDI-IMS in combination with enzyme digestion for the direct analysis
of oligosaccharides as a major component of histopathological samples. 相似文献
102.
Nobuaki Hoshino 《Annals of the Institute of Statistical Mathematics》2012,64(3):457-474
The present article investigates a class of random partitioning distributions of a positive integer. This class is called
the limiting conditional compound poisson (LCCP) distribution and characterized by the law of small numbers. Accordingly the
LCCP distribution explains the limiting behavior of counts on a sparse contingency table by the frequencies of frequencies.
The LCCP distribution is constructed via some combinations of conditioning and limiting, and this view reveals that the LCCP
distribution is a subclass of several known classes that depend on a Bell polynomial. It follows that the limiting behavior
of a Bell polynomial provides new asymptotics for a sparse contingency table. Also the Neyman Type A distribution and the
Thomas distribution are revisited as the basis of the sparsity. 相似文献
103.
Miyaoka H Abe Y Sekiya N Mitome H Kawashima E 《Chemical communications (Cambridge, England)》2012,48(6):901-903
Total synthesis of antimalarial diterpenoid (+)-kalihinol A, isolated from marine sponge Acanthella sp., is achieved. This total synthesis involves regioselective alkylation of an epoxide, construction of a tetrahydropyran ring by iodo-etherification, construction of a cis-decalin ring by intramolecular Diels-Alder reaction, isomerization of cis-decalin to trans-decalin, and subsequent functionalization of the trans-decalin ring. 相似文献
104.
R Shen T Iwasaki J Terao N Kambe 《Chemical communications (Cambridge, England)》2012,48(74):9313-9315
Cu-catalyzed cross-coupling of unactivated secondary alkyl iodides with alkyl Grignard reagents in the presence of 1,3-butadiene as a ligand precursor was developed. The use of 1,3-butadiene resulted in improved yields of alkyl-alkyl products with improved selectivities. 相似文献
105.
The software release game developed in Ref. 1 is reconsidered in the framework of a two-person nonzero-sum game of timing. More precisely, noisy-type software release strategies are derived in closed form under two different criteria as well as an alternative silent-type software release strategy. Our method overcomes the fatal problem in Ref. 1 and has an advantage on computational tractability. Also, the method can be extended directly to obtain noisy-type strategies. 相似文献
106.
Hiromasa Nishikiori Nobuaki Tanaka Tsuneo Fujii 《Research on Chemical Intermediates》2000,26(5):469-482
Dip-coated thin films including rhodamine B have been prepared using the sol-gel reaction of tetraethyl orthosilicate under
relative humidity of 30% and 60%. They have been aged under relative humidity of 20%, 60%, and 95% for 5 days. According to
the absorption spectra, just after the preparation of the films and under higher humidity, a larger amount of the dimers (H-and
J-types) were formed in the films. Five days after the preparation of the films and aged under higher humidity, the H-dimer
increased. On the other hand, the J-dimer increased, regardless of humidity under which the films were aged. 相似文献
107.
108.
Y. Teraoka 《Journal of Optimization Theory and Applications》1986,49(3):477-487
We consider a marksmanship contest in which Player I has one silent bullet, whereas Player II has one noisy bullet, the first contestant to hit his target wins, and the contest is to be terminated at a random timeT with cdfH(t). The model is a silent-noisy version of our previous paper (Ref. 8), and an extension of silent-noisy duel to nonzero-sum games of timing under an uncertain environment. It is shown that the uncertainty on the termination of the contest has influence on the equilibrium strategies and the equilibrium values, but the silent player has no advantages over the noisy one, in such a nonzero-sum model.The author thanks Professor M. Sakaguchi, Osaka University, who contributed to the research on mathematical decision-making problems and expresses appreciation for his continuous encouragement and guidance. The author also thanks Professor G. Kimeldorf, The University of Texas at Dallas, who invited the author to his university. Finally, the author expresses appreciation to Professors K. Sugahara and W. Fukui, Himeji Institute of Technology, for their encouragement and support. 相似文献
109.
Yuma Wakamiya Dr. Makoto Ebine Mariko Murayama Hiroyuki Omizu Prof. Dr. Nobuaki Matsumori Prof. Dr. Michio Murata Prof. Dr. Tohru Oishi 《Angewandte Chemie (International ed. in English)》2018,57(21):6060-6064
Amphidinol 3 (AM3) is a marine natural product produced by the dinoflagellate Amphidinium klebsii. Although the absolute configuration of AM3 was determined in 1999 by extensive NMR analysis and degradation of the natural product, it was a daunting task because of the presence of numerous stereogenic centers on the acyclic carbon chain and the limited availability from natural sources. Thereafter, revisions of the absolute configurations at C2 and C51 were reported in 2008 and 2013, respectively. Reported herein is the revised absolute configuration of AM3: 32S, 33R, 34S, 35S, 36S, and 38S based on the chemical synthesis of partial structures corresponding to the C31–C67 fragment of AM3 in combination with degradation of the natural product. The revised structure is unique in that both antipodal tetrahydropyran counterparts exist on a single carbon chain. The structural revision of AM3 may affect proposed structures of congeners related to the amphidinols. 相似文献
110.
Nobuaki Obata 《Monatshefte für Mathematik》1997,124(4):317-335
Let
be a barreled locally convex space. A continuous operator on
is called anequicontinuous generator if {
n
/n!;n=0,1,2,...} is an equicontinuous family of operators. For each equicontinuous generator a one-parameter group of operators is constructed by means of power series. There is a one-to-one correspondence between the equicontinuous generators and the locally equicontinuous holomorphic one-parameter groups of operators. If two equicontinuous generators 1, 2 satisfy [1,2]=2 for some thena1+b2 is also an equicontinuous generator for anya, b. These general results are applied to a study of operators on white noise functions. In particular, a linear combination of the number operator and the Gross Laplacian, which are natural infinite dimensional analogues of a finite dimensional Laplacian, is always an equicontinuous generator. This result contributes to the Cauchy problems in white noise (Gaussian) space.Work supported by Alexander von Humboldt-Stiftung and Japan Society for Promotion of Sciences 相似文献