Syntheses and characterization of 16‐arm star and star diblock copolymer and AB8 9‐miktoarm star copolymer via NMRP and ROP from dendritic multifunctional macroinitiators

A dendritic macroinitiator having 16 TEMPO‐based alkoxyamines, Star‐16 , was prepared by the reaction of a dendritic macroinitiator having eight TEMPO‐based alkoxyamines, [G‐3]‐OH , with 4,4′‐bis(chlorocarbonyl)biphenyl. The nitroxide‐mediated radical polymerization (NMRP) of styrene (St) from Star‐16 gave 16‐arm star polymers with PDI of 1.19–1.47, and NMPR of 4‐vinylpyridine from the 16‐arm star polymer gave 16‐arm star diblock copolymers with PDI of 1.30–1.43. The ring‐opening polymerization of ε‐caprolactone from [G‐3]‐OH and the subsequent NMRP of St gave AB₈ 9‐miktoarm star copolymers with PDI of 1.30–1.38. The benzyl ether linkages of the 16‐arm star polymers and the AB₈ 9‐miktoarm star copolymers were cleaved by treating with Me₃SiI, and the resultant poly(St) arms were investigated by size exclusion chromatography (SEC). The SEC results showed PDIs of 1.23–1.28 and 1.18–1.22 for the star polymers and miktoarm stars copolymers, respectively, showing that they have well‐controlled poly(St) arms. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1159–1169, 2007.     

Serial magnetic resonance imaging in patients following acute myocardial infarction.

The detection of serial changes in magnetic resonance (MR) signal intensity of the heart following acute myocardial infarction may provide a useful method of characterizing tissue healing. Fourteen patients with acute Q-wave infarction underwent T2-weighted, spin-echo cardiac imaging during hospitalization, followed by one or more additional MR studies (total 31) over a 6- to 27-wk period (mean: 3 mo). Visual assessment of the images demonstrated a gradual reduction in signal intensity and localization of the bright signal to the subendocardium of the infarction region over the three-mo study period. A quantitative measurement of signal intensity (infarction/normal myocardium) fell from 1.81 +/- 0.42 on the initial study to 1.34 +/- 0.37 (p less than 0.05) at a mean of 14 wk. Two patients had an increase in signal intensity on the follow-up study and both patients had been readmitted with acute coronary syndromes. In summary, characterization of changes in signal intensity may provide a useful method of assessing myocardial healing following acute myocardial infarction. Further studies are indicated to determine the prognostic significance of these parameters.     

A Relationship Among Gentzen's Proof-Reduction,Kirby-Paris' Hydra Game and Buchholz's Hydra Game

We first note that Gentzen's proof-reduction for his consistency proof of PA can be directly interpreted as moves of Kirby-Paris' Hydra Game, which implies a direct independence proof of the game (Section 1 and Appendix). Buchholz's Hydra Game for labeled hydras is known to be much stronger than PA. However, we show that the one-dimensional version of Buchholz's Game can be exactly identified to Kirby-Paris' Game (which is two-dimensional but without labels), by a simple and natural interpretation (Section 2). Jervell proposed another type of a combinatorial game, by abstracting Gentzen's proof-reductions and showed that his game is independent of PA. We show (Section 3) that this Jervell's game is actually much stronger than PA, by showing that the critical ordinal of Jervell's game is φ_ω (0) (while that of PA or of Kirby-Paris' Game is φ₁ (0) = ?₀) in the Veblen hierarchy of ordinals.     

Approximate empirical formula for X-ray intensity in radioactive nuclides

Known intensities of X-rays emitted from radioactive nuclides have been plotted against atomic number, and a distinct correlation has been found only for EC-decay type nuclides, as follows: 2.75 Z^1.06>X>0.507 Z^1.06, and X_{most probable}=1.18 Z^1.06, where X is the absolute percentage and Z is the atomic number of the decay product.     

PI Mtoyoura: a new PI M subtype found by separator and hybrid isoelectric focusing

In the course of a population study of alpha 1-antitrypsin polymorphism by separator isoelectric focusing, a variant phenotype having a somewhat narrower spacing than PI M1M3 was observed in a Japanese blood donor. Family studies by hybrid isoelectric focusing in a carrier ampholyte-supplemented immobilized pH gradient from 4.35-4.65 revealed that the products of the responsible gene, PI*Mtoyoura, were extremely close but slightly cathodal to those of PI*M1. The difference in isoelectric point between them corresponded to the resolving limit of isoelectric focusing. For this reason, although the propositus' father was deduced to have the genotype PI*M1/PI*Mtoyoura, the products of these two genes failed to form a double band pattern. Thus, the gene frequency for PI*Mtoyoura was unknown. These findings, however, indicate that a further microheterogeneity in the PI M subtype exists at least in the Japanese.     

He I (584 Å) photoelectron spectra and photoionization cross sections of atomic chlorine and bromine

Well-resolved He I photoelectron spectra of atomic chlorine and bromine have been obtained without serious background electrons, giving rise to relative photoelectron intensities associated with differential photoionization cross sections at an angle of 90° with respect to the incident 584 Å radiation.     

Anti-inflammatory activity of new guaiane type sesquiterpene from Wikstroemia indica

In our investigation of in vitro anti-allergic screening of medicinal herbal extracts, the ethyl acetate extract of the root of Wikstroemia indica was observed to inhibit nitric oxide (NO) production in a lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma) activated murine macrophage-like cell line, RAW 264.7. Fractionation of the active extract led to the isolation of one new guaiane type sesquiterpene, indicanone (1), and two known biflavonoids, sikokianin B (2) and sikokianin C (3). 1 inhibited NO production with IC50 values at 9.3 microM and also inhibit the inducible nitric oxide synhase (iNOS) gene expression. This is the first report of NO production inhibitory activity of Wikstroemia indica and supports the pharmacological use of it, which has been employed as an herbal medicine for the treatment of inflammation.