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111.
Lipid rafts are considered as specialized microdomains within the plasma membrane with unique lipid compositions different from surrounding membranes. Following T-cell receptor (TCR) stimulation, lipid rafts assemble in T-cell/antigen-presenting cell (APC) contact site known as the immunological synapse, inner leaflets of which serve as activation or docking sites for downstream signaling components. To understand the signaling events occurring in lipid rafts, we globally analyzed dynamic changes in lipid raft proteins during TCR/CD28 costimulation using 2-D fluorescence difference gel electrophoresis. We detected multiple spots whose intensities were enhanced after costimulation, and identified proteins in these spots by PMF. Identified proteins include Src family tyrosine kinases, tyrosine phosphatase, phosphatidylinositol 3-kinase (PI3-kinase), actin-binding proteins, and regulators for small GTPases. Of particular interest, a number of pleckstrin homology (PH) domain-containing proteins were identified. Biochemical and histochemical analyses confirmed the translocation of these proteins from cytosol to lipid rafts. We also demonstrated that these proteins assembled at the T-cell/APC interface. These results indicate the efficacy of our system to systematically analyze dynamics of lipid raft proteins during extracellular stimulation. 相似文献
112.
Yamada K Mukaihata N Kawahara T Tada H 《Langmuir : the ACS journal of surfaces and colloids》2007,23(16):8593-8596
The synergy of an anodic-biased alpha-Fe2O3 film and a cationic surfactant molecular assembly leads to a high visible light induced activity for 2-naphthol oxidation and high stability. An abrupt increase in the photocatalytic activity at a surfactant concentration of ca. 0.2 mmol dm(-3) results from the adsolubilization of 2-naphthol into the hydrophobic nanospace of the surfactant bilayer formed on the alpha-Fe2O3 surface. Also, the surfactant bilayer provides sustainable photocurrent during the reaction. 相似文献
113.
We study the relative position of four (closed) subspaces in a Hilbert space. For any positive integer n, we give an example of exotic indecomposable system
of four subspaces in a Hilbert space whose defect is
. By an exotic system, we mean a system which is not isomorphic to any closed operator system under any permutation of subspaces.
We construct the examples using certain nice sequences construced by Jiang and Wang in their study of strongly irreducible
operators.
Dedicated to Professor Masahiro Nakamura on his 88th birthday 相似文献
114.
We prove the following theorem: For a connected noncomplete graph G, let τ(G): = min{dG(u) + dG(v)|dG(u, v) = 2}. Suppose G is a 3-connected noncomplete graph. Then through each edge of G there passes a cycle of length ≥ min{|V(G)|, τ (G) − 1}. © 1997 John Wiley & Sons, Inc. 相似文献
115.
It is well‐known that every planar graph has a vertex of degree at most five. Kotzig proved that every 3‐connected planar graph has an edge xy such that deg(x) + deg (y) ≤ 13. In this article, considering a similar problem for the case of three or more vertices that induce a connected subgraph, we show that, for a given positive integer t, every 3‐connected planar graph G with |V(G)| ≥ t has a connected subgraph H of order t such that Σx∈V(H) degG(x) ≤ 8t − 1. As a tool for proving this result, we consider decompositions of 3‐connected planar graphs into connected subgraphs of order at least t and at most 2t − 1. © 1999 John Wiley & Sons, Inc. J Graph Theory 30: 191–203, 1999 相似文献
116.
Ryuichi Wada Tomoki Nakayama Tetsuya Hiyama Yasushi Fujiyoshi Naoyuki Kurita 《Isotopes in environmental and health studies》2017,53(6):646-659
Isotope ratios of carbon dioxide and water vapour in the near-surface air were continuously measured for one month in an urban area of the city of Nagoya in central Japan in September 2010 using laser spectroscopic techniques. During the passages of a typhoon and a stationary front in the observation period, remarkable changes in the isotope ratios of CO2 and water vapour were observed. The isotope ratios of both CO2 and water vapour decreased during the typhoon passage. The decreases can be attributed to the air coming from an industrial area and the rainout effects of the typhoon, respectively. During the passage of the stationary front, δ13C–CO2 and δ18O–CO2 increased, while δ2H–H2Ov and δ18O–H2Ov decreased. These changes can be attributed to the air coming from rural areas and the air surrounding the observational site changing from a subtropical air mass to a subpolar air mass during the passage of the stationary front. A clear relationship was observed between the isotopic CO2 and water vapour and the meteorological phenomena. Therefore, isotopic information of CO2 and H2Ov could be used as a tracer of meteorological information. 相似文献
117.
H. Imao M. Tarek K. Michishio Y. Enomoto T. Shimoyama Y. Kanai N. Kuroda A. Mohri H. Higaki H. Saitoh H. A. Torii Y. Nagata H. Toyoda Y. Matsuda Y. Nagashima Y. Yamazaki 《Hyperfine Interactions》2009,194(1-3):71-76
Our group “ASACUSA MUSASHI” has established an efficient way for accumulating antiprotons and extracting them as intense ultra-slow mono-energetic beams at the CERN-AD facility. This novel beam opens new frontiers for investigating a variety of physics. For realizing H? spectroscopy and the test for charge-parity-time symmetry, we have also developed the cusp trap, a combination of an anti-Helmholz superconducting coil and a multi-ring electrode trap, for trapping both antiprotons and positrons and then synthesizing antihydrogens. Recently, the cusp trap was practically used to accumulate antiprotons. The last piece for synthesizing antihydrogens in the cusp trap is the positron accumulator. We have developed a compact system to effectively accumulate positrons based on N2 gas-buffer scheme with a specially designed high precision cylindrical multi-ring electrode trap. The recent progress of the developing work is an important milestone for upcoming antihydrogen science of ASACUSA MUSASHI. 相似文献
118.
We discuss the scenario with TeV-scale right-handed neutrinos, which are accessible at future colliders, while holding down tiny seesaw-induced masses and sizable couplings to the standard-model particles. The signal with tri-lepton final states and large missing transverse energy is appropriate for studying collider signatures of the scenario with extra spatial dimensions. We show that the LHC experiment generally has a potential to discover the signs of extra dimensions and the origin of small neutrino masses. 相似文献
119.
Phase transitions in MgAl2O4 were examined at 21-27 GPa and 1400-2500 °C using a multianvil apparatus. A mixture of MgO and Al2O3 corundum that are high-pressure dissociation products of MgAl2O4 spinel combines into calcium-ferrite type MgAl2O4 at 26-27 GPa and 1400-2000 °C. At temperature above 2000 °C at pressure below 25.5 GPa, a mixture of Al2O3 corundum and a new phase with Mg2Al2O5 composition is stable. The transition boundary between the two fields has a strongly negative pressure-temperature slope. Structure analysis and Rietveld refinement on the basis of the powder X-ray diffraction profile of the Mg2Al2O5 phase indicated that the phase represented a new structure type with orthorhombic symmetry (Pbam), and the lattice parameters were determined as a=9.3710(6) Å, b=12.1952(6) Å, c=2.7916(2) Å, V=319.03(3) Å3, Z=4. The structure consists of edge-sharing and corner-sharing (Mg, Al)O6 octahedra, and contains chains of edge-sharing octahedra running along the c-axis. A part of Mg atoms are accommodated in six-coordinated trigonal prism sites in tunnels surrounded by the chains of edge-sharing (Mg, Al)O6 octahedra. The structure is related with that of ludwigite (Mg, Fe2+)2(Fe3+, Al)(BO3)O2. The molar volume of the Mg2Al2O5 phase is smaller by 0.18% than sum of molar volumes of 2MgO and Al2O3 corundum. High-pressure dissociation to the mixture of corundum-type phase and the phase with ludwigite-related structure has been found only in MgAl2O4 among various A2+B3+2O4 compounds. 相似文献
120.
Arc-disjoint in-trees in directed graphs 总被引:2,自引:0,他引:2
Given a directed graph D = (V,A) with a set of d specified vertices S = {s
1,…, s
d
} ⊆ V and a function f: S → ℕ where ℕ denotes the set of natural numbers, we present a necessary and sufficient condition such that there exist Σ
i=1
d
f(s
i
) arc-disjoint in-trees denoted by T
i,1,T
i,2,…, for every i = 1,…,d such that T
i,1,…, are rooted at s
i
and each T
i,j
spans the vertices from which s
i
is reachable. This generalizes the result of Edmonds [2], i.e., the necessary and sufficient condition that for a directed
graph D=(V,A) with a specified vertex s∈V, there are k arc-disjoint in-trees rooted at s each of which spans V. Furthermore, we extend another characterization of packing in-trees of Edmonds [1] to the one in our case.
Supported by JSPS Research Fellowships for Young Scientists.
Supported by the project New Horizons in Computing, Grand-in-Aid for Scientific Research on Priority Areas, MEXT Japan. 相似文献