Regulated Incorporation of Two Different Metal Ions into Programmed Sites in a Duplex by DNA Polymerase Catalyzed Primer Extension

Metal‐mediated base pairs formed by the coordination of metal ions to natural or artificial bases impart unique chemical and physical properties to nucleic acids and have attracted considerable interest in the field of nanodevices. Ag^I ions were found to mediate DNA polymerase catalyzed primer extension through the formation of a C–Ag^I–T base pair, as well as the previously reported C–Ag^I–A base pair. The comparative susceptibility of dNTPs to Ag^I‐mediated enzymatic incorporation into the site opposite cytosine in the template was shown to be dATP>dTTP?dCTP. Furthermore, two kinds of metal ions, Ag^I and Hg^II, selectively mediate the incorporation of thymidine 5′‐triphosphate into sites opposite cytosine and thymine in the template, respectively. In other words, the regulated incorporation of different metal ions into programmed sites in the duplex by DNA polymerase was successfully achieved.     

Helical polyacetylenes carrying 2,2,6,6‐tetramethyl‐1‐piperidinyloxy and 2,2,5,5‐tetramethyl‐1‐pyrrolidinyloxy moieties: Their synthesis,properties, and function

2,2,6,6‐Tetramethyl‐1‐piperidinyloxy (TEMPO)‐ and 2,2,5,5‐tetramethyl‐1‐pyrrolidinyloxy (PROXYL)‐containing (R)‐1‐methylpropargyl TEMPO‐4‐carboxylate ( 1 ), (R)‐1‐methylpropargyl PROXYL‐3‐carboxylate ( 2 ), (rac)‐1‐methylpropargyl PROXYL‐3‐carboxylate ( 3 ), (S)‐1‐propargylcarbamoylethyl TEMPO‐4‐carboxylate ( 4 ), and (S)‐1‐propargyloxycarbonylethyl TEMPO‐4‐carboxylate ( 5 ) (TEMPO, PROXYL) were polymerized to afford novel polymers containing the TEMPO and PROXYL radicals at high densities. Monomers 1–3 and 5 provided polymers with moderate number‐average molecular weights of 8200–140,900 in 49–97% yields in the presence of (nbd)Rh⁺[η⁶‐C₆H₅B^?(C₆H₅)₃], whereas 4 gave no polymer with this catalyst but gave polymers possessing low M_n (3800–7500) in 56–61% yield with [(nbd)RhCl]₂‐Et₃N. Poly( 1 ), poly( 2 ), and poly( 4 ) took a helical structure with predominantly one‐handed screw sense in THF and CHCl₃ as well as in film state. The helical structure of poly( 1 ) and poly( 2 ) was stable upon heating and addition of MeOH, whereas poly( 4 ) was responsive to heat and solvents. All of the free radical‐containing polymers displayed the reversible charge/discharge processes, whose capacities were in a range of 43.2–112 A h/kg. In particular, the capacities of poly( 2 )–poly( 5 )‐based cells reached about 90–100% of the theoretical values regardless of the secondary structure of the polymer, helix and random. Poly( 1 ), poly( 2 ), and poly( 4 ) taking a helical structure exhibited better capacity tolerance towards the increase of current density than nonhelical poly( 3 ) and poly( 5 ) did. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5431–5445, 2007     

Global Existence and Uniqueness of Solutions to the Maxwell-Schrödinger Equations

The time local and global well-posedness for the Maxwell-Schrödinger equations is considered in Sobolev spaces in three spatial dimensions. The Strichartz estimates of Koch and Tzvetkov type are used for obtaining the solutions in the Sobolev spaces of low regularities. One of the main results is that the solutions exist time globally for large data.     

Retrospective analyses of atmospheric polycyclic and nitropolycyclic aromatic hydrocarbons in an industrial area of a western site of Japan.

Thirteen polycyclic aromatic hydrocarbons (PAHs) and four nitropolycyclic aromatic hydrocarbons (NPAHs) on the surfaces of airborne particulates, which were collected at an industrial area of a western site of Japan during periods from 1976 to 1998, were retrospectively analyzed. PAHs and NPAHs were extracted from airborne particulates using hexane with ultrasonication, and then analyzed by HPLC systems with fluorescence detection and chemiluminescence detection, respectively. The total concentrations (mean +/- SD, n = 34) were 15.54 +/- 21.24 ng/m3 for PAHs and 5.85 +/- 8.16 pg/m3 for NPAHs. The concentrations of PAHs and NPAHs were found to be highest during the period between 1979 and 1982, and then reduced. The annual concentrations of PAHs and NPAHs were highly correlated with those of air pollutants from motor vehicle origin, such as carbon monoxide, suspended particulates and non-methane hydrocarbons. The results suggested that motor vehicle emissions were one of the predominant sources of atmospheric PAHs and NPAHs.     

Bionanodot monolayer array fabrication for nonvolatile memory application

A polyelectrolyte thin film which was simply spin-coated on a substrate showed the high-density adsorption of bionanodot-accommodated ferritins through electrostatic interaction. Solution pH adjustment facilitated the control of adsorption density to a value grater than 80% of the theoretical maximum density. The formed polyelectrolyte film was very thin and vulnerable like protein, therefore, only the array with densely adsorbed bionanodot was left on the substrate after organic component removal. The floating nanodot gate type MOS capacitor fabricated with this bionanodot array showed a memory effect, and no negative influences of polymer such as carrier trapping on the capacitance-voltage characteristics was observed.     

Specific ionic conduction in poly[oligo (oxyethylene glycol) methacrylate] (PMEO)–Li salt complexes under high‐pressure CO2

We measured the ionic conductivity of amorphous poly[oligo (oxyethylene glycol) methacrylate] (PMEO)–lithium salt complexes under a CO₂ pressure varying from 0.1 to 20 MPa. The pressure dependence of the conductivity was positive, and the conductivity was higher than that under an inert gas such as N₂. The ion‐conductive behavior has been modeled using both the Vogel–Tammann–Fulcher (VTF) equation and activation volume theory. The calculated parameters of the VTF equation show that CO₂ that had permeated into the PMEO matrix acts as solvent molecules to dissolve ions and lower the glass transition temperature at high pressures. The ionic conduction in PMEO complexes under high‐pressure CO₂ was scarcely related to the VTF parameters and activation volume equations. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3151–3158, 2005     

Activities of polyhedral vanadium-containing silsequioxane-based catalysts for photo-assisted oxidation of hydrocarbons

The catalytic activity of a polyhedral vanadium-containing silsesquioxane ((c-C₅H₉)₇Si₇O₁₂VO, 1b) with a cubic core structure towards the selective photooxidation of benzene, cyclohexane, and adamantane was examined under O₂ (1 atm) at around 300 K. The reaction of benzene in the presence of 1b afforded phenol selectively, but the TON was low (≈1.4). Complex 1b showed high activity towards the reaction of cyclohexane (TON ≈16) and adamantane (TON≈7.0). The order of the reactivity of the C−H bonds in adamantane was tertiary C−H> secondary C−H. In addition to 1b, the mixtures of vanadyl bisacetylacetonate and incompletely-condensed silsesquioxanes with silanol functionality showed relatively high activities, although vanadyl bisacetylacetonate itself was not effective. The degradation of the catalysts in the course of the reaction was partly suppressed in the presence of molecular sieves-4A.     

Synthesis of 2-acylindole-3-acetic acids: a novel base-mediated indole synthesis

An efficient and expedient synthetic route to 2-acylindole-3-acetic acids is described. This work first demonstrates a one-pot room-temperature indole ring construction via the in situ generation of indoline intermediate.     

Reversed-phase high-performance liquid chromatography of several metal-8-quinolinethiol complexes.

The reversed-phase high-performance liquid chromatography of 8-quinolinethiol (Hqt) complexes of Fe, Co, Ni, Cu, Zn, Hg and Pb on an octadecyl-bonded silica gel stationary phase was examined. The Pb complex dissociated in the column. The retention and separation of other complexes depended on the composition of the mobile phase. EDTA as an additive displaced the Zn complex and eliminated its peak. All the other metal complexes and also Hqt and its disulphide were separated in 23 min by using methanol-water (82:18, v/v) as the mobile phase. The complexes formed by the reaction of Co(II) and Hqt gave three peaks, which were assigned as fac(S)-CoIII(qt)3, mer(S)-CoIII(qt)3 and CoII(qt)2, respectively. This method is applicable to the simultaneous determination of Fe, Co, Ni, Cu and Hg.     

Waves on fractal-like manifolds and effective energy propagation

Summary. We prove that the average speed of effective energy propagation of the waves satisfying long wave length condition in some globally fractal-like manifolds is asymptotically zero. Received: 17 March 1995 / In revised form: 16 September 1997