Reductive coupling of carbonyl compounds using lanthanum metal

We found that lanthanum metal was an excellent agent for the reduction of carbonyl compounds in the presence of a catalytic amount of iodine. When carbonyl compounds were treated with lanthanum metal in the presence of a catalytic amount of iodine, the reductive coupling of the carbonyl compounds proceeded efficiently to afford the corresponding vic‐diols in moderate to good yields. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:81–85, 2000     

Photoluminescent coordination polymer bulk glasses and laser-induced crystallization

We synthesized luminescent coordination polymer glasses composed of d¹⁰ metal cyanides and triphenylphosphine through melt-quenching and mechanical milling protocols. Synchrotron X-ray total scattering measurements and solid-state NMR revealed their one-dimensional chain structures and high structural dynamics. Thermodynamic and photoluminescence properties were tunable by the combination of heterometallic ions (Ag⁺, Au⁺, and Cu⁺) in the structures. The glasses are moldable and thermally stable, and over centimeter-sized glass monoliths were fabricated by the hot-press technique. They showed high transparency over 80% from the visible to near-infrared region and strong green emission at room temperature. Furthermore, the glass-to-crystal transformation was demonstrated by laser irradiation through the photothermal effect of the glasses.

Over centimeter-sized luminescent coordination polymer glasses were fabricated. They showed high transparency (over 80%) and strong green emission at room temperature. The glass-to-crystal transformation by laser irradiation was demonstrated.     

Biverlactones A-D, new circumventors of arbekacin resistance in MRSA, produced by Penicillium sp. FKI-4429

Biverlactones, new circumventors of arbekacin resistance in methicillin-resistant Staphylococcus aureus (MRSA) were isolated from a culture broth of Penicillium sp. FKI-4429. Their structures were elucidated by spectroscopic studies, including various NMR experiments. Biverlactones A-D had novel skeletons, consisting of a lactone ring conjugated with exo- or endo-olefin, a carboxylic group and a characteristic alkyl side chain in common.     

Liver function assessment with three 13C breath tests by two-point measurements

In this study, we performed three breath tests – l-[1-¹³C ]phenylalanine breath test (PBT), l-[1-¹³C ] methionine breath test, and [¹³C]methacetin breath test (MethaBT) – in patients with chronic liver disease to determine the optimal timing of expired air collection for diagnosing chronic liver disease and evaluating the grade of fibrosis. The subjects were 61 adults with normal livers, 98 chronic hepatitis patients, and 91 liver cirrhosis patients. We investigated the relationships of breath test results with routine biochemical tests and the Child–Pugh score, as well as the diagnostic capacities of the breath tests for liver dysfunction/cirrhosis and grade of liver fibrosis. For the diagnosis of liver cirrhosis and correlations with liver fibrosis, the accuracy of the PBT at 30 min (PBT30) was similar to that of the MethaBT at 15 min (Metha15). For liver function assessment by two-point measurement with ¹³C breath tests, we recommend the PBT30 and the Metha15.     

Temperature dependence of the elastic modulus of crystalline regions of isotactic poly(4-methyl-1-pentene)

The elastic modulus E ₁ of crystalline regions of isotactic poly(4-methyl-1-pentene) (P4M1P) in the direction parallel to the chain axis and its temperature dependence were investigated by x-ray diffraction. E ₁ values for the (001) and (007) planes of P4M1P agreed well at 4.1 GPa at room temperature. This small E value could be attributed both to the contracted helical conformation (7/2 helix) and to a large cross-sectional area of P4M1P in the crystalline regions. Though the lattice distortion of the first kind increased and partial destruction of crystallites occurred with increasing stress, the stress-strain curve for the crystal lattice was linear up to 80 MPa. However, the E₁ value remained unchanged up to 150°C. The lattice spacing for the (007) plane increased monotonously with increasing temperature, with a thermal expansion coefficient of 0.9 × 10^?4 K^?1. These phenomena were in contrast with the temperature dependence of E ₁ values of various polymers previously reported, in which E ₁ decreased in the temperature region where the thermal expansion coefficient changed. It is considered for P4M1P that the axail thermal molecular mitions which cause the decrement of E₁ do not take place and that the deformation mechanism of the chain molecules remains unchnaged in the crystalline regions over the temperature and stress range studied.     

A simple coarse-grained model for interacting protein complex

ABSTRACT

We present a simple coarse-grained model in which each amino acid residue is represented by one coarse-grained particle for interacting protein complex. In order to determine the coarse-grained potential function of the interaction between amino acid residues, free energy profile as a function of the distance between amino acid side chains is investigated by using all-atom molecular dynamics simulations with thermodynamic integration method. The Langevin dynamics simulation with Gō-like model and our coarse-grained model reproduces homotetramer complex structure of GCN4-pLI and shows that interaction between hydrophobic amino acid residues promote the association of GCN4-pLI monomers.     

Excess Entropy Production in Quantum System: Quantum Master Equation Approach

For open systems described by the quantum master equation (QME), we investigate the excess entropy production under quasistatic operations between nonequilibrium steady states. The average entropy production is composed of the time integral of the instantaneous steady entropy production rate and the excess entropy production. We propose to define average entropy production rate using the average energy and particle currents, which are calculated by using the full counting statistics with QME. The excess entropy production is given by a line integral in the control parameter space and its integrand is called the Berry–Sinitsyn–Nemenman (BSN) vector. In the weakly nonequilibrium regime, we show that BSN vector is described by \(\ln \breve{\rho }_0\) and \(\rho _0\) where \(\rho _0\) is the instantaneous steady state of the QME and \(\breve{\rho }_0\) is that of the QME which is given by reversing the sign of the Lamb shift term. If the system Hamiltonian is non-degenerate or the Lamb shift term is negligible, the excess entropy production approximately reduces to the difference between the von Neumann entropies of the system. Additionally, we point out that the expression of the entropy production obtained in the classical Markov jump process is different from our result and show that these are approximately equivalent only in the weakly nonequilibrium regime.     

Walk-Off Ring Coupling Type CO Laser

As a complementary scheme to a coupling-hole type laser, a walk-off ring coupling type laser is proposed to extract a donut shaped beam by shrinking the diameter of one of the stable resonator mirrors. This was successfully applied to a conventional slow axial-flow CO laser. First, finding the intensity distribution close to the Gaussian profile by using a partially transparent mirror in a hemispherical configuration for coupling, we obtain the relationship between the mirror radius and the effective transmittance. Then, using several mirrors with a diameter smaller than the Gaussian profile above instead of the partially transparent mirror, the output power with the donut shape was optimized to yield the maximum power, together with theoretical treatments. This resulted in an optimum mirror diameter of 4.2 mm, which corresponds to the optimum transmittance of 5-6% for the CO laser having the gain parameter G≅0.34, the inherent loss ā ≅ 0.07, and the measure of partial homogeneity m¯ =; 0.5. This value is exactly the same as that of the coupling-hole mirror. Some application feasibilities are also discussed.     

The Flag-Transitive C 3-Geometries of Finite Order

It is shown that a flag-transitive C ₃-geometry of finite order (x, y) with x2 is either a finite building of type C ₃ (and hence the classical polar space for a 6-dimensional symplectic space, a 6-dimensional orthogonal space of plus type, a 6- or 7-dimensional hermitian space, a 7-dimensional orthogonal space, or an 8-dimensional orthogonal space of minus type) or the sporadic A ₇-geometry with 7 points.