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81.
Hirokazu Nishimura 《International Journal of Theoretical Physics》2000,39(5):1221-1231
It is well known that supersmooth functions are more akin to holomorphicfunctions than to smooth functions. The ultimate object of study in complexgeometry is not merely complex manifolds, but complex spaces, in whichholomorphic functions may be nilpotent and consequently invisible from ageometric viewpoint. Supergeometers have long been searching for an appropriatedefinition of supermanifold, for which many classical results in the theory ofsmooth manifolds can naturally be superized. However, they have not proceededfurther in quest of a supersmooth equivalent of complex space. The principalobject of this paper is to introduce the notion of supersmooth superspace intosupergeometry after the classical definition of complex space in complexgeometry, and then to build a good model of synthetic supergeometry after themanner of Dubuc and Taubin (1983), thereby superseding Yetter (1988). Themodel to be constructed is a Grothendieck topos encompassing the category ofG
-supermanifolds and G
-mappings as a full subcategory. 相似文献
82.
BACKGROUND: alpha-Galactosylceramide (alpha-GalCer) can be presented by CD1d molecules of antigen-presenting cells, and is known to induce a potent NKT cell-dependent cytotoxic response against tumor cells. However, the main effector cells in alpha-GalCer-induced antitumor immunity are still controversial. METHODS: In order to elucidate the cell phenotype that plays the most important role in alpha-GalCer-induced antitumor immunity, we purified and analyzed tumor-infiltrating leukocytes (TILs) from liver metastatic nodules of a colon cancer cell line (Colon26), comparing alpha-GalCer- and control vehicle-treated mice. Flow cytometry was performed to analyze cell phenotype in TILs and IFN-gamma ELISA was performed to detect antigen-specific immune response. RESULTS: Flow cytometry analysis showed a significantly higher infiltration of NK cells (DX5+, T cell receptor alphabeta (TCR)-) into tumors in alpha-GalCer-treated mice compared to vehicle-treated mice. The DX5+TCR+ cell population was not significantly different between these two groups, indicating that these cells were not the main effector cells. Interestingly, the CD8+ T cell population was increased in TILs of alpha-GalCer-treated mice, and the activation level of these cells based on CD69 expression was higher than that in vehicle-treated mice. Moreover, the number of tumor-infiltrating dendritic cells (DCs) was increased in alpha-GalCer-treated mice. IFN-gamma ELISA showed stronger antigen-specific response in TILs from alpha-GalCer-treated mice compared to those from vehicle-treated mice, although the difference between these two groups was not significant. CONCLUSIONS: In alpha-GalCer-induced antitumor immunity, NK cells seem to be some of the main effector cells and both CD8+ T cells and DCs, which are related to acquired immunity, might also play important roles in this antitumor immune response. These results suggest that alpha-GalCer has a multifunctional role in modulation of the immune response. 相似文献
83.
Oishi T Hagiwara K Kinumi T Yamakawa Y Nishijima M Nakamura K Arimoto H 《Organic & biomolecular chemistry》2003,1(15):2626-2629
The effects of Soto's 'beta-sheet breaker peptide' and its polymer on PrPSc formation in ScN2a cells were investigated. Surface plasmon resonance study indicated that direct binding between PrP(81-145) and the 'beta-sheet breaker peptide' is not specific and may not play a major role in the inhibition of PrPSc formation. 相似文献
84.
Hiromi Shinohara Hirokazu Shibata Dieter Whrle Hiroyuki Nishide 《Macromolecular rapid communications》2005,26(6):467-470
Summary: A membrane of a cobalt tetraazaporphyrin polymer complex was prepared with a nanometer thickness and used as an oxygen‐facilitated transport membrane. Rapid and reversible oxygen binding to the cobalt tetraazaporphyrin complex with a polymeric imidazole ligand was observed at low temperature. Oxygen transport through the membrane was facilitated and a high (oxygen/nitrogen) permselectivity of 28 was obtained.
85.
A new infrared-spectroscopic method to characterize acid sites of zeolites using small and weakly basic molecules such as diatomic and monoatomic molecules is reviewed. It has been revealed that N2 is an effective probe molecule to characterize both Brønsted acidity and Lewis acidity of H-form zeolites. The characteristics of the N 2 probe are discussed in detail in comparison with the CO probe. O2 and rare gases have also been applied to monitor the strong acid sites in the H-form zeolites. Further, the studies of the adsorption of water on H-form zeolites are shortly reviewed: a recent IR study of the H2
18O adsorption on H-ZSM-5 has given direct experimental evidence that the main feature of the observed IR bands is due to the hydrogen-bonded adsorption of water on the Brønsted acid sites. 相似文献
86.
87.
Dr. Shu Xu Daisuke Unabara Prof. Dr. Daisuke Uemura Prof. Dr. Hirokazu Arimoto 《化学:亚洲杂志》2014,9(1):367-375
The enantioselective total synthesis of the bioactive marine natural products pinnaic acid and halichlorine is reported in detail. Our total synthesis features the construction of the five‐membered ring and C9 and C13 stereogenic centers through a palladium‐catalyzed trimethylenemethane [3+2] cyclization; the installation of the nitrogen atom through a regioselective Beckmann rearrangement of a poorly reactive ketone; the stereoselective cyclization of the spiro ring through a four‐step, one‐pot hydrogenation–cyclization; and efficient connection of the sterically hindered lower chain through a reduced‐pressure cross olefin metathesis reaction. 相似文献
88.
The transannular Diels-Alder (TADA) reaction was applied to the synthesis of the CDE ring system of nakiterpiosin (1). Tetracyclic compound 25 may be a key intermediate in the total synthesis of 1. 相似文献
89.
Masahiro Kihara Shin‐Ichiro Kohama Shota Umezono Kanji Wakabayashi Shinichi Yamazaki Kunio Kimura 《Journal of polymer science. Part A, Polymer chemistry》2011,49(5):1088-1096
Poly(p‐oxybenzoyl) (POB) crystals were prepared by reaction‐induced crystallization during direct polymerization of p‐hydroxybenzoic acid in the presence of boronic anhydrides. Polymerizations were carried out at 300 °C in dibenzyltoluene at a concentration of 1% with three kinds of anhydrides of boronic acid such as 3,4,5‐trifluorophenylboronic acid (TFB), 4‐methoxyphenylboronic acid (MPB) and 4‐biphenylboronic acid (BPB). The POB crystals were formed as precipitates in the solution and the morphology was considerably influenced by both the structure of the boronic anhydride and its concentration (cB). Needle‐like crystals were firmed in the presence of TFB anhydride (TFBA) at cBs of 5 and 10 mol % by the spiral growth of lamellae. Spherical aggregates of slab‐like crystals were formed at cBs from 50 to 100 mol %. The polymerization with MPB anhydride and BPB anhydride (BPBA) also yielded the needle‐like crystals at cBs of 50 and 5 mol %, respectively. The polymerization with TFBA at lower cB was favorable to prepare the needle‐like crystal. Molecular weight was also influenced by the structure of the boronic anhydride and cB. Mn increased generally with cB and BPBA gave the highest Mn of 14.7 × 103 at cB of 100 mol %. The loose packing of the molecules in the crystal caused by the bulkiness of the end‐groups made the polymerization in the crystals more efficiently. Morphology and molecular weight of the POB crystals could be controlled by the chemical structure and the content of boronic anhydride. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
90.
Hirokazu Sato Shusaku Hamada Roberto M. Sertkawa Tatsuya Nishimura Takashi Usui Hideo Sekino 《高压研究》2013,33(1-6):403-413
Abstract Continuous flames have been observed in Supercritical water oxidation (scWO) of isopropyl alcohol (IPA), using a vertical continuous reactor with sapphire windows and a mixing nozzle. Two types of continuous flame were confirmed: the one was long pale blue colored and the other was red short cone shaped, changing blue to red at around air ratio 2.0. The flame was strongly influenced by IPA concentration, air ratio and design of the mixing nozzle. Results for decomposition of PA are presented for IPA concentrations ranging from 600 up to 28260 ppm as TOC and initial reactor temperatures, were mostly around 490°C, at 25 MPa. Decomposition rate at steady state was over 99.9%. Experimentally measured CO2 and O2 concentrations at the flue gas were in good agreement with theoretically calculated values. Even for low air ratio as 1.1, high decomposition rate without CO, NO, NO2 was achieved. 相似文献