β(1,3) Branched heptadeca- and linear hexadeca-saccharides possessing an aminoalkyl group as a strong ligand to dectin-1

In this report, we describe the convergent synthesis of β(1,3) oligosaccharides containing an aminoalkyl group. The branched heptadecasaccharide and linear hexadecasaccharide acted as ligands of dectin-1 whose binding affinity was only 10-fold weaker than that of natural SPG and exhibited dectin-1 agonist activity.     

One-pot hydrothermal synthesis of an assembly of magnetite nanoneedles on a scaffold of cyclic-diphenylalanine nanorods

The assembly of metal oxide nanoparticles (NPs) on a biomolecular template by a one-pot hydrothermal synthesis method is achieved for the first time. Magnetite (Fe₃O₄) nanoneedles (length: ~100 nm; width: ~10 nm) were assembled on cyclic-diphenylalanine (cFF) nanorods (length: 2–10 μm; width: 200 nm). The Fe₃O₄ nanoneedles and cFF nanorods were simultaneously synthesized from FeSO₄ and l-phenylalanine by hydrothermal synthesis (220 °C and 22 MPa), respectively. The samples were analyzed by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (IR), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry. Experimental results indicate that Fe₃O₄ nanoneedles were assembled on cFF nanorods during the hydrothermal reaction. The composite contained 3.3 wt% Fe₃O₄ nanoneedles without any loss of the original magnetic properties of Fe₃O₄.     

Global dynamics of a reaction–diffusion system with mass conservation

We study global dynamics of a mass conserved reaction–diffusion system. First, we show the global-in-time existence of the solution with compact orbit. Then the dynamical stability of local minima associated with a variational function is proven.     

Lewis-Pairing-Induced Electrochemiluminescence Enhancement from Electron Donor-Acceptor Diads Decorated with Tris(pentafluorophenyl)borane as an Electrochemical Protector

This study reports an effective peripheral decoration of organic donor-acceptor diads with B(C₆F₅)₃ for stabilizing electrogenerated radical ions. By employing a common p-type organic semiconductor benzothienobenzothiophene (BTBT) as the donor, tetracoordinate boron complexes showed improved solution electrochemiluminescence (ECL) intensity, reaching a 156-fold increase compared to that of the parent diad. The unprecedented Lewis-pairing-induced ECL enhancement is attributed to the multiple roles of B(C₆F₅)₃: 1) redistributing frontier orbitals, 2) facilitating electrochemical excitation, and 3) restricting molecular motions. Furthermore, B(C₆F₅)₃ converted the molecular arrangement of BTBT from conventional 2D herringbones into 1D π-stacks. This robust, highly ordered columnar nanostructure allowed red-shifting of the crystalline film ECL with electrochemical doping through the electronic coupling pathways of BTBT. Our approach will facilitate the development of elaborate metal-free ECL systems.     

POSSIBLE INVOLVEMENT OF MEMBRANE DAMAGE IN THE IN ACTIVATION BY BROAD-BAND NEAR-UV RADIATION IN Saccharomyces cerevisiae CELLS

Multiple cellular effects of near-UV radiation (300-380 nm) on inactivation, disruption of the permeability barrier and induction of gene conversion at the trp 5 locus were simultaneously measured in the same culture of a diploid strain of the yeast Saccharomyces cerevisiae in order to assess the critical lethal damage. Inactivation of exponential phase cells in water appeared to be closely related to the disruption of the permeability barrier. Inactivation and membrane damage were remarkably oxygen dependent, whereas the induction of genetic changes was very low and dependent much less on oxygen. The dependence on the temperature for inactivation and membrane damage was both low, conforming with the expectation that the processes are mainly photochemical and not enzymatic. These features are very contrasted with the characteristics of far-UV radiation effects. Possible involvement of membrane damage in near-UV inactivation of exponential phase yeast cells is discussed.     

Flows around rotating disks with and without rim-shroud gap

Experimental and numerical approaches have been used to study the effect of the radial rim-shroud gap on the flow structures found around a rotating disk in a finite cylindrical casing. When the radius of the disk and the inner radius of the casing are comparable and there is no radial gap, instabilities bring spiral rolls with a positive front angle in the Bödewadt layer on the end wall of the stationary casing. When the disk radius is smaller than the inner radius of the casing, vortex flows appear within the radial gap between the disk rim and the side wall of the casing. If the disk is thin, but not too thin, disturbances generated by these vortex flows proceed inward and the spiral rolls with a negative front angle appear in the Bödewadt layer. In the case of a thick disk, wavy Taylor vortex-like flow appears in the radial gap. The disturbances formed by the vortex flow do not well propagate into the inner region, and a flow pattern of bead-like vortices or a chain of vortices consisting of a series of small vortices are found around the disk in the visualized figure parallel to the disk.     

Analysis of Cu segregation to oxide–metal interface of Ni‐based alloy in a metal‐dusting environment

Hard X‐ray photoelectron spectroscopy (HX‐PES) has been realized using high‐brilliance synchrotron radiation. High‐energy photon excitation enables us to probe photoelectrons with larger escape depth compared to conventional PES. This allows us to conduct, without destruction, a study of the embedded interface of materials as the oxide‐ metal interface. We apply HX‐PES to investigate for Cu segregation in the oxide–metal interface during metal‐dusting corrosion. The effective concentration of Cu in the segregation was estimated a few times higher than the bulk concentration. These results on the interface layer can explain the variation in the corrosion resistance. Copyright © 2008 John Wiley & Sons, Ltd.     

Cage-catalyzed Knoevenagel condensation under neutral conditions in water

A cationic coordination cage dramatically accelerates the Knoevenagel condensation of aromatic aldehydes in water under neutral conditions. The addition of a nucleophile to the aldehyde to generate anionic intermediates seems to be facilitated by the cationic environment of the cavity. The products are ejected from the cage as a result of the host-guest size discrepancy. As a result, the condensation is promoted by a catalytic amount of the cage.     

A direct identification method for current dipoles from electromagnetic fields

We discuss the identification problem for current dipoles in a spherically symmetric conductor. This mathematical model is used for a biomedical inverse problem such as the source current identification for the human brain activity. We have already proposed a direct identification method for this inverse source problem using observations of the magnetic fields outside of the conductor. One of the difficulties of current dipole identification using the magnetic fields is caused by the fact that magnetic field does not include any information about the radial component of dipole moments. In this paper, we consider an improvement of the direct method to identify both radial and tangential components of current dipole moments by combining electric and magnetic observation data. Furthermore, our approach is effective in the case where the number of dipoles is unknown.