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141.
TextThe Bowman–Bradley theorem asserts that the multiple zeta values at the sequences obtained by inserting a fixed number of twos between add up to a rational multiple of a power of π. We establish its counterpart for multiple zeta-star values by showing an identity in a non-commutative polynomial algebra introduced by Hoffman.VideoFor a video summary of this paper, please click here or visit http://www.youtube.com/watch?v=LpqA2OJ6vP8. 相似文献
142.
Nishikimi A Uruno T Duan X Cao Q Okamura Y Saitoh T Saito N Sakaoka S Du Y Suenaga A Kukimoto-Niino M Miyano K Gotoh K Okabe T Sanematsu F Tanaka Y Sumimoto H Honma T Yokoyama S Nagano T Kohda D Kanai M Fukui Y 《Chemistry & biology》2012,19(4):488-497
Highlights? CPYPP binds to DOCK2 DHR-2 domain and inhibits its catalytic activity ? CPYPP inhibits DOCK2-mediated Rac activation in cells ? The structural features of CPYPP required for its inhibitory effect were revealed ? CPYPP inhibits lymphocyte migration and activation in vitro and in vivo 相似文献
143.
We reported previously that sustained release matrix tablets showed zero-order drug release without being affected by pH change. To understand drug release mechanisms more fully, we monitored the swelling and erosion of hydrating tablets using magnetic resonance imaging (MRI). Three different types of tablets comprised of polyion complex-forming materials and a hydroxypropyl methylcellulose (HPMC) were used. Proton density- and diffusion-weighted images of the hydrating tablets were acquired at intervals. Furthermore, apparent self-diffusion coefficient maps were generated from diffusion-weighted imaging to evaluate the state of hydrating tablets. Our findings indicated that water penetration into polyion complex tablets was faster than that into HPMC matrix tablets. In polyion complex tablets, water molecules were dispersed homogeneously and their diffusivity was relatively high, whereas in HPMC matrix tablets, water molecule movement was tightly restricted within the gel. An optimal tablet formulation determined in a previous study had water molecule penetration and diffusivity properties that appeared intermediate to those of polyion complex and HPMC matrix tablets; water molecules were capable of penetrating throughout the tablets and relatively high diffusivity was similar to that in the polyion complex tablet, whereas like the HPMC matrix tablet, it was well swollen. This study succeeded in characterizing the tablet hydration process. MRI provides profound insight into the state of water molecules in hydrating tablets; thus, it is a useful tool for understanding drug release mechanisms at a molecular level. 相似文献
144.
The characteristics of decaying homogeneous turbulence under strong density stratification have been studied using direct
numerical simulations. While our previous study dealt with rotating stratified turbulence, here we investigate the detailed
flow structure of stratified turbulence without rotation especially at low-Prandtl number. By assuming a low-Prandtl-number
fluid, e.g. liquid sodium: Pr ≈ 0.01, gallium: Pr ≈ 0.025, internal gravity waves are markedly attenuated due to the large thermal conductivity, and turbulence soon reaches
a two-component state, where vertical energy, coupled with potential energy, significantly decays, and becomes negligible
as observed experimentally (Praud et al. in J Fluid Mech 522:1–33, 2005). In the horizontal plane, there appear large-scale
vortices with vertical vorticity, and those with the same sign of vorticity increase their horizontal length scale by merging
with each other. In the vertical plane, highly sheared regions represented by horizontal vorticity also tend to horizontally
increase their length scale and become layered structures by the combined effects of vortex coalescence and energy cascade
into higher vertical wavenumbers.
相似文献
145.
Effect of the stoichiometry on the electronic structure of the Ni(111)/α-Al2O3(0001) interface: a first-principles investigation 下载免费PDF全文
In this paper first-principles calculations of Ni(111)/α-Al2O3(0001) interfaces have been performed, and are compared with the preceding results of the Cu (111)/α-Al2O3(0001) interface [2004 Phil. Mag. Left. 84 425]. The AI- terminated and O-terminated interfaces have quite different adhesion mechanisms, which are similar to the Cu(111)/α Al2O3(0001) interface. For the O-terminated interface, the adhesion is caused by the strong O-2p/Ni-3d orbital hybridization and ionic interactions. On the other hand, the adhesion nature of the Al-terminated interface is the image-like electrostatic and Ni-Al hybridization interactions, the latter is substantial and cannot be neglected. Charge transfer occurs from Al2O3 to Ni, which is opposite to that in the O=terminated interface. The charge transfer direction for the Al-terminated and O-terminated Ni(111)/α-A1203(0001) interfaces is similar to that in the corresponding Cu(111)/α- Al2O3(0001) interface, but there exist the larger charge transfer quantity and consequent stronger adhesion nature, respectively. 相似文献
146.
The a.c. magnetic susceptibility (χ) was measured for (C6H5CH2NH3)2CuCl4 (φC1Cl) above 4.2K, and two-consecutively anomalous behaviours of χ were observed at 6K and 6.9K. Brief discussions about these phenomena were given in relation to the two-dimensionality of φC1Cl system. 相似文献
147.
A submodular polyhedron is a polyhedron associated with a submodular function. This paper presents a strongly polynomial time algorithm for line search in submodular polyhedra with the aid of a fully combinatorial algorithm for submodular function minimization. The algorithm is based on the parametric search method proposed by Megiddo. 相似文献
148.
Kazuhiko Miyazaki Hirohumi Kasada Yusuke Nishigaki Hideaki Yoshioka Shingo Nihonmori 《International Journal of Infrared and Millimeter Waves》1994,15(10):1663-1668
By replacing the conventional (non line-selective) unstable resonator, we succeeded in developing the very high power line-selective (line-tunable) CO2 laser as a pumping source for high power molecular gas (e.g.NH3) lasers in the infrared and far-infrared regions.The experiments were performed by using the very high power CO2 laser (4A unit of Lekko VIII) at The Institute of Laser Engineering, Osaka University.The output power of 9R(30)9.22µ m line from the developed CO2 laser, for instance, exceeded 0.5GW/pulse (50J/pulse with pulse width of 100nsec). 相似文献
149.
Koichi Nagano 《Archiv der Mathematik》2007,88(2):173-180
We construct several non-trivial examples of CAT(1) spaces by using the idea of free construction.
Received: 29 August 2005
Partially supported by the MEXT Grant-in-Aid for scientific research, and by the 2004 JSPS
Postdoctoral Fellowships for Research Abroad. 相似文献
150.