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We propose a new type of solution to the ultradiscrete hungry Lotka-Volterra (uhLV) equation. For the solution, the periodic phase is introduced into the known soliton and the extended soliton becomes a traveling wave showing a pe...
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We propose a new type of solution to the ultradiscrete hungry Lotka-Volterra (uhLV) equation. For the solution, the periodic phase is introduced into the known soliton and the extended soliton becomes a traveling wave showing a periodic variation. We call this type of wave a 'periodic phase soliton' (PPS). The solution has two forms of expression: one is the 'perturbation form' and the other is the 'ultradiscrete permanent form'. We analyze the interaction among PPSs and solitons. Moreover, we give the outline of proof to show that the solution satisfies the bilinear equation of the uhLV equation.
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In this paper we study microlocal singularities of solutions to Schrodinger equations on scattering manifolds, i.e.. noncompact Riemannian manifolds with asymptotically conic ends. We characterize the wave front set of the solutio...
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In this paper we study microlocal singularities of solutions to Schrodinger equations on scattering manifolds, i.e.. noncompact Riemannian manifolds with asymptotically conic ends. We characterize the wave front set of the solutions in terms of the initial condition and the classical scattering maps under the nontrapping condition. Our result is closely related to a recent work by Hassell and Wunsch, though our model is more general and the method, which relies heavily on scattering theoretical ideas, is simple and quite different. In particular, we use an Egorov-type argument in the standard pseudodifferential symbol classes, and avoid using Legendre distributions. In the proof, we employ a microlocal smoothing property in terms of the radially homogenous wave front set, which is more precise than the preceding results.
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The MeOH extract from the flowers of Bellis perennis was found to show pancreatic-lipase inhibitory activity (IC50 455 mu g/ml). From the extract, seven new triterpene saponins named perennisaponins 0 (1; IC50 163 mu M), H (2; 137...
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The MeOH extract from the flowers of Bellis perennis was found to show pancreatic-lipase inhibitory activity (IC50 455 mu g/ml). From the extract, seven new triterpene saponins named perennisaponins 0 (1; IC50 163 mu M), H (2; 137 mu M), 1(3: 147 mu M), J (4; 148 mu M), K (5; 223 mu M), L (6; 81.4 mu M), and M (7; 195 mu M) were isolated as pancreatic lipase inhibitors. The stereostructures of 1-7 were elucidated on the basis of chemical and spectroscopic evidence.
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The MeOH extract and its BuOH-soluble fraction (crude saponin fraction) from the flower buds of chinese tea plant (Camellia sinensis (L.) O. KUNTZE; Fujian Province) were found to exhibit accelerating effects on gastrointestinal t...
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The MeOH extract and its BuOH-soluble fraction (crude saponin fraction) from the flower buds of chinese tea plant (Camellia sinensis (L.) O. KUNTZE; Fujian Province) were found to exhibit accelerating effects on gastrointestinal transit in mice and inhibitory effects against pancreatic lipase. From the BuOH-soluble fraction, three new acylated oleanane-type triterpene oligoglycosides, chakasaponins I, II, and III (1-3, resp), were isolated together with 13 known compound. The chemical structures 1-3 were elucidated on the basis of chemical and physicochemical evidence. Compounds 1-3 showed accelerating effects on gastrointestinal transit in mice and inhibitory effects against porcine pancreatic lipase (IC50 = 150 -530 mu M).
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The acetyl esterified calixarene (CA) derivatives were prepared from calix[4]resorcinarene (CRA), and p-tert-butylcalixarene (BCA[n], n = 4, 6, 8), respectively. Using these CA derivatives as curing agents, the thermal curing reac...
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The acetyl esterified calixarene (CA) derivatives were prepared from calix[4]resorcinarene (CRA), and p-tert-butylcalixarene (BCA[n], n = 4, 6, 8), respectively. Using these CA derivatives as curing agents, the thermal curing reactions of two multifunctional epoxy resins (jER 828, 186 g/equiv., and ESCN, 193.7 g/equiv.) were investigated. The temperatures of glass transition (T-g) and decomposition (T-d(10%)) were measured by DSC and TGA, respectively. Based on the yields, T(g)s, and T(d)s of the thermal cured jER 828 epoxy resin with CRA-E100, the curing conditions were optimized to be tetrabutylphosphonium bromide (TBPB) as catalyst in NMP at 160 degrees C for 15 h. Under this curing condition, the cured materials of jER 828 or ESCN using various CA derivatives as curing agents were prepared. Except for BCA4 derivatives, the yields of thermal curing reaction were higher than 90%. T(g)s and T(d)(10%)s of the resultant cured materials were in the range of 113-248 degrees C and 363-404 degrees C, respectively. These results mean that the cured epoxy resins with excellent T(g)s were successfully formed by using CA derivatives as curing agents. It was also found that the T(g)s of cured epoxy resins were strongly affected by the degree of esterification of CA derivatives.
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To understand the stabilization, folding, and functional mechanisms of proteins, it is very important to understand the structural and thermodynamic properties of the molten globule state. In this study, the global structure of th...
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To understand the stabilization, folding, and functional mechanisms of proteins, it is very important to understand the structural and thermodynamic properties of the molten globule state. In this study, the global structure of the acid molten globule state, which we call MG1, of horse cytochrome c at low pH and high salt concentrations was evaluated by solution X-ray scattering (SXS), dynamic light scattering, and circular dichroism measurements. MG1 was globular and slightly (3%) larger than the native state, N. Calorimetric methods, such as differential scanning calorimetry and isothermal acid-titration calorimetry, were used to evaluate the thermodynamic parameters in the transitions of N to MG1 and MG1 to denatured state D of horse cytochrome c. The heat capacity change, ΔC_p, in the N-to-MG1 transition was determined to be 2.56 kJ K~(-1) mol~(-1), indicating the increase in the level of hydration in the MG1 state. Moreover, the intermediate state on the thermal N-to-D transition of horse cytochrome c at pH 4 under low-salt conditions showed the same structural and thermodynamic properties of the MG1 state in both SXS and calorimetric measurements. The Gibbs free energy changes (ΔG) for the N-to-MG1 and N-to-D transitions at 15℃ were 10.9 and 42.2 kJ mol~(-1), respectively.
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Weed management is a major issue in organic farming systems. Although interseeding cover crops is one alternative to herbicides, cover crops often suppress not only weeds but also main crops. Therefore, using cover crops for weed ...
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Weed management is a major issue in organic farming systems. Although interseeding cover crops is one alternative to herbicides, cover crops often suppress not only weeds but also main crops. Therefore, using cover crops for weed control without adverse effects on main crop growth is important. To verify the effect of cover crops on competition between main crops, cover crops and weeds in a snowy-cold region, main crops soybean (Glycine max Merr.) in 2005 and maize (Zea mays L.) in 2006 were grown with cover crops winter rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth), respectively. The cover crops were sown on three sowing dates: before main crop planting (Pre-MC), on the same date of main crop planting (Syn-MC) and after main crop planting (Post-MC). A plot without cover crops (Sole-MC) was used as a control. The dry weight (DW), vegetation cover ratio (VCR), vertical community structure and chlorophyll content were measured to estimate the competition between main crops, cover crops and weeds. Weed DW was suppressed significantly by sowing cover crops in both soybean and maize. This weed suppression was associated with the increase of VCR of main crops plus cover crops at the early growth stage of main crops. Soil seed banks of dominant weed also became lower by sowing cover crops, implying the importance of proper weed management for suppressing weeds successively. In addition, the sowing dates of cover crops had large effects on main crops DW especially in maize, i.e., it was significantly lower in Pre-MC and Syn-MC than in Post-MC. Although the cover crop height was markedly shorter than the main crop height, the chlorophyll content of the main crops was significantly lower when cover crops were sown earlier. These results suggest that the growth inhibition of main crops by cover crops was partly caused by competition for nutrients between main crops and cover crops, and this growth inhibition was alleviated when cover crops were sown after the establishment of main crops. Consequently, soybean yield was the highest in Post-MC and decreased by 29%, 18% and 7% in Sole-MC, Pre-MC and Syn-MC, respectively, and maize yield was also the highest in Post-MC and decreased by 68%, 100% and 24% in Sole-MC, Pre-MC and Syn-MC, respectively. It was concluded that weeds could be controlled effectively by sowing cover crops after planting main crops in organic farming systems in a snowy-cold region.
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We present experimental results verifying the optical robustness of a 1 X 1 multimode interference (MMI) device that is directly butt coupled with optical fibers at 70 degrees C for 1050 h and discuss the gradual increase of polar...
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We present experimental results verifying the optical robustness of a 1 X 1 multimode interference (MMI) device that is directly butt coupled with optical fibers at 70 degrees C for 1050 h and discuss the gradual increase of polarization dependent loss. Based on this structure, an electro-optic (EO) MMI waveguide device that can control the output optical power by using an electrode structure located directly on top of the multimode is presented. As a proof of principle, we demonstrate the switching operation of the EO-MMI device using commercially available chromophore as the active EO material.
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The neutron capture cross section of Np-237 has been measured relative to the B-10(n, alpha)Li-7* cross section by the time-of-flight method in the energy range from 0.02 to 100 eV. The 46 MeV electron linear accelerator at the Re...
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The neutron capture cross section of Np-237 has been measured relative to the B-10(n, alpha)Li-7* cross section by the time-of-flight method in the energy range from 0.02 to 100 eV. The 46 MeV electron linear accelerator at the Research Reactor Institute, Kyoto University, was used as a pulsed neutron source. The BGO scintillation detector was employed in conjunction with the flash ADC-based data taking system for measurement and data accumulation. For the first time the capture cross section of Np-237 in resonance energy range was measured using the total energy gamma-ray detector. The results of present measurements have been compared with the evaluated capture cross sections of ENDF/B-VI and JENDL-3.3, as well as with the data measured by other authors.
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Peripheral nerve sheath tumors (PNSTs) are rare in chickens and their etiology remains to be elucidated. In this study, a naturally occurring PNST in a Japanese native fowl (Gallus gallus domesticus) was pathologically examined an...
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Peripheral nerve sheath tumors (PNSTs) are rare in chickens and their etiology remains to be elucidated. In this study, a naturally occurring PNST in a Japanese native fowl (Gallus gallus domesticus) was pathologically examined and the strain of avian leukosis virus (ALV) isolated from the neoplasm was characterized by molecular biological analysis. The fowl presented with a firm subcutaneous mass in the neck. The mass, connected to the adjacent spinal cord (C9-14), was microscopically composed of highly cellular tissue of spindle cells arranged in interlacing bundles, streams, and palisading patterns with Verocay bodies and less cellular tissue with abundant collagen. Immunohistochemically, neoplastic cells were divided into two types: perineurial cells positive for vimentin, glucose transporter 1 (GLUT1), and claudin1; and Schwann cells positive for vimentin, occasionally positive for S-100 alpha/beta but negative for GLUT1. Based on these findings, a diagnosis of neurofibrosarcoma was made. The complete nucleotide sequence of an ALV strain, CTS_5371, isolated from the neoplasm was determined and phylogenetic analysis indicated that the strain was a novel recombinant virus from avian leukosis/sarcoma viruses previously reported. Additionally, experimental infection revealed that CTS_5371 induced the proliferation of Schwnm cells and perineurial cells. These results suggest that this ALV strain has the ability to induce PNSTs in chickens.
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