Electrical classification of single red blood cell deformability in high-shear microchannel flows

A sensor that can efficiently and sequentially measure the deformability of individual red blood cell (RBC) flowing along a microchannel is described. Counter-electrode-type microsensors are attached to the channel bottom wall, and as RBCs pass between the electrodes, the time series of the electric resistance is measured. An RBC is deformed by the high shear flow to a degree dependent upon its elastic modulus. Hence, the profile of the resistance, which is unique to the shape of the RBC, can be analyzed to obtain the deformability of each cell. First, theoretical and experimental analyses were conducted to identify the specific AC frequency at which the effect of the electric double layer formed on the electrode surface is minimized. Measurements were then conducted upon samples of normal human RBCs and glutaraldehyde-treated (rigidified) RBCs to evaluate the feasibility of the present method. In addition, simultaneous visualization of RBC deformation was performed using a high-speed camera. Normal RBCs were observed to have a degree of deformation index (DI) of around 0.57, whereas the rigidified RBCs was DI = 0 in the microchannel. The experimental measurements showed a strong correlation between the half-width of the maximum of the resistance distribution and the DI of the RBC.     

Experimental study of toroidal shock wave focusing in a compact vertical annular diaphragmless shock tube

The paper reports results of experiments regarding toroidal shock wave focusing in a vertical shock tube as a part of a series of converging shock wave studies. This compact vertical shock tube was designed to achieve a high degree of reproducibility with minimum shock formation distance by adopting a diaphragmless operating system. The shock tube was manufactured in the Institute of Fluid Science, Tohoku University. An aspheric lens shaped cylindrical test section was connected at the open end of the shock tube to visualize the diffraction and focusing of the toroidal shock wave released from the ring shaped shock tube opening. Pressure transducers were flush mounted on the shock tube’s test section to measure pressure histories at the converging test section. Double exposure holographic interferometry was employed to quantitatively visualize the shock waves. The whole sequence of toroidal shock wave diffraction, focusing, and its reflection from the symmetrical axis were successfully studied. The transition of reflected shock waves was observed.     

Synthesis and binding properties of a noncovalent molecularly imprinted testosterone-specific polymer

In this study, molecular imprinting was used to develop a method based on noncovalent interactions for synthesis of a testosterone-specific polymer. The effect of the different template–monomer ratios, the particle sizes of polymers, and chromatographic mobile phases on steroid–polymer interactions are discussed. The polymer obtained was found to interact specifically with testosterone, while other steroids under study were eluted close to the void volume in the HPLC experiments. Batch rebinding studies in acetonitrile were undertaken to quantitatively evaluate the affinity of the polymer for testosterone. During this experiment, the testosterone concentration was measured in two ways: spectrophotometrically and by HPLC on a column with testosterone-specific imprinted polymer synthesized by us. Both methods resulted in similar values of association constants and the number of binding sites. However, the second method has obvious advantages when the analyzed solution contains a mixture of optically dense compounds. The results obtained focus on the two-point binding nature of the imprinted polymer–testosterone interaction and the significant role of hydrogen bonds between the OH group of testosterone and carboxy group of methacrylic acid residues inside specific recognition sites of the imprinted polymer. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1725–1732, 1998     

Correction to: High-Dimensional Quadratic Classifiers in Non-sparse Settings

Methodology and Computing in Applied Probability -     

Synthesis of chloroboron(III) 3,4,12,13,21,22- hexabromosubnaphthalocyanine under high dilution conditions and comparative studies of effects of halogenation on physicochemical properties of subnaphthalocyanines

Chloroboron(III) hexabromosubnaphthalocyanine was prepared by cyclotrimerization of 6,7-dibromo-2,3-naphthalenedicarbonitrile in the presence of BCl₃ under high dilution conditions, that is 7.4?mM of dicarbonitrile in o-dichlorobenzene-xylene (1:1). It was converted to fluoroboron(III) hexabromosubnaphthalocyanine by the reaction with AgBF₄. Fluorescence quantum yields of chloroboron(III) hexafluoro-, hexachloro-, hexabromo-, and hexaiodosubnaphthalocyanine were 0.22, 0.20, 0.11, 0.05, respectively, indicating that heavy atom effects of Br and I effectively deactivated the singlet excited states. Thermal decomposition temperature (5% weight loss in the TG curve) of fluoroboron(III) hexabromosubnaphthalocyanine was the highest (359?°C) and that of chloroboron(III) hexafluorosubnaphthalocyanine was the lowest (221?°C) among hexahalosubnaphthalocyanines. The hexabromosubnaphthalocyanine served as a substrate of Sonogashira coupling, and proved to be a useful intermediate for further functionalization of subnaphthalocyanines.     

Dependence of the Physical Properties on the Cation Ordering in the New Ternary Phosphide ZnCu2P8

: The air-stable phosphide, ZnCu₂P₈, was synthesized from its elements in gram amounts. It crystallizes in the Cu_2.5In_0.5P₈ structure type [C2/c, Z = 4, a = 1110.8(2) pm, b = 964.7(2) pm, c = 752.7(1) pm, β = 110.027(3)°], and is the first ternary phosphide in the system Zn/Cu/P. Its crystal structure consists of two-dimensional, layered polyphosphide-anions, separated by tetrahedrally-coordinated cations. 135 symmetry independent configurations, each with a different and specific Zn²⁺ and Cu⁺ arrangement, where explored with density functional methods. Whereby, each of the 135 cation ordering pattern has a diverse bandgap, and the total energies vary in the range of 1 eV. As several configurations with low energy are close in energy, an intrinsic disorder is discussed as origin of the promising low lattice thermal conductivity, observed.     

Cationic polymerization of n‐hexyloxyallene by using halogen‐bonding organocatalysts

The cationic polymerization of n‐hexyloxyallene was investigated by using halogen‐bonding organocatalysts ( Cat A – Cat D ). Although the neutral catalyst Cat C showed a poor polymerization activity, iodine‐carrying bidentate cationic catalyst Cat A brought about the smooth polymerization giving rise to a polymer with M_n of 2710 under [ Cat A ]:[IBVE‐HCl]:[monomer] = 10:10:500 in mM concentrations. Judging from the color change of polymerization system and electrospray ionization mass spectra of recovered catalyst, the decomposition of organocatalyst was suggested. When α‐bromodiphenylmethane was used as an initiator, the relatively controlled polymerization proceeded at the low monomer conversion likely due to the weak halogen‐bonding interaction of Cat A with the bromide anion. On the other hand, bromine‐carrying bidentate catalyst Cat D gave low‐molecular‐weight polymers (M_n < 1550) to be less suitable for polymerization. From the ¹H‐NMR spectrum, it was found that the 1,2‐polymerization unit and 2,3‐polymerization unit are included in 75:25. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2436–2441     

Spin-orbit interaction in unoccupied surface states

Spin-orbit interaction (SOI) has been investigated extensively in the last decade, for its potential impact on spintronics, which has become particularly important in surface science. This article reviews our recent works on SOI in the image potential states (IPSs), which have been widely studied as an ideal model system for electron dynamics at solid surfaces. By combining high-energy resolution bichromatic two-photon photoemission spectroscopy and circular dichroism (CD), we have investigated the Rashba-type SOI of IPSs. We measured the splitting of n?=?1 IPS on Au(1?0?0) surface and determined its Rashba parameter. We also discuss the splitting of IPS on a graphene-covered Ir(1?1?1) surface presented recently based on selection rules for CD measurements and the calculated band structure.     

Formation of dimer, trimer, and tetramer of C60 and C70 by γ-ray, charged-particle irradiation, and their HPLC separation

C₆₀ and C₇₀ fullerenes were irradiated by high-energy γ-rays and charged particles. Coalesced products of C₆₀ and C₇₀ have been isolated and detected in the liquid phase by a radiochromatographic technique. It was found that not only ¹¹C radioactive fullerene dimer, trimer, and possibly tetramer were produced by a recoil implantation process following nuclear reaction, but also such non-radioactive coalesced products were produced by the recombination process after ionization by γ-rays or charged particles.