Objectives-To evaluate the influences of chronic alcohol consumption on brain volume among social drinkers, as it is well known that alcohol misusers have a high risk of brain shrinkage. Methods-Frontal lobe volumes on MRI were compared with the current alcohol habits of consecutive 1432 non-alcoholic subjects. Results-After adjusting for other variables, age was found to be the most powerful promoting factor for the shrinkage with a odds ratio of 2.8 (95% confidence interval (95% CI) 1.23-3.06) for each 10 years of age. Regarding alcohol habit, 667 of the subjects were abstainers, and 157, 362, and 246 of the subjects were light (average 88.2 g ethanol/week), moderate (181.2 g/week), and heavy (418.1 g/week) drinkers, respectively. Moderate alcohol consumption did not increase the incidence of frontal lobe shrinkage (odds ratio 0.98; 95% CI 0.73-1.33), whereas heavy drinkers were at a higher risk compared with abstainers (1.80; 1.32-2.46). The contributory rate of alcohol consumption for frontal lobe shrinkage was 11.3%. Conclusion-The brain tends to shrink physiologically with age. Heavy alcohol consumption seems to exaggerate this shrinkage in social drinkers. Moderate alcohol consumption does not seem to aVect brain volume. (J Neurol Neurosurg Psychiatry 2001;71:104-106)

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SUMMARY: Peroxidase-catalyzed oxidative polymerization of m-substituted phenols has been performed in a mixture of a water-miscible organic solvent and buffer at room temperature under air to give a new class of polyphenols. The catalysts used were horseradish and soybean peroxidases (HRP and SBP, respectively). In the polymerization of m-cresol using HRP as the catalyst, effects of an organic solvent, buffer pH, and their mixed ratio have been systematically investigated with respect to the polymer yield, solubility, and molecular weight. The HRP-catalyzed polymerization of m-cresol in an equivolume mixture of methanol and phosphate buffer (pH 7) produces the polymer in a high yield, which is readily soluble in polar solvents such as methanol, acetone, N,N-dimethylformamide, and dimethyl sulfoxide. The polymer was estimated to consist of a mixture of phenylene and oxyphenylene units from NMR and IR analyses as well as titration of the residual phenolic moiety of the polymer. The polymerization behavior of the m-substituted monomers greatly depends on the enzyme type. In using SBP as a catalyst, the polymer yield increases as a function of the bulkiness of the substituent, whereas the opposite tendency was observed in case of HRP catalysis. The relationships between the monomer substituent and the polymerization behavior are discussed in terms of the HOMO level of the monomer and the substituent volume.

Highly concentrated solutions composed of lithium bis­(fluorosulfonyl)­imide (LiFSI) and sulfolane (SL) are promising liquid electrolytes for lithium metal batteries because of their high anodic stability, low flammability, and high compatibility with lithium metal anodes. However, it is still challenging to obtain the stable lithium metal anodes in the concentrated electrolytes due to their poor wettability to the conventional polyolefin separators. Here, we report that the highly concentrated 1:2.5 LiFSI/SL electrolyte coupled with a three-dimensionally ordered macroporous polyimide (3DOM PI) separator enables the stable lithium plating/stripping cycling with an average Coulombic efficiency of ca. 98% for over 400 cycles at 1.0 mA cm–2. The 3DOM PI separator shows good electrolyte wettability and large electrolyte uptake due to its high porosity and polar constituent of the imide structure, allowing superior cycling performance in the highly concentrated solution, compared with the polyolefin separators. Electrochemical and spectroscopic analyses reveal that the superior cycling stability in the concentrated electrolyte is attributed to the formation of highly stable and Li+ ion conductive solid electrolyte interphase (SEI) layer derived from FSI– anions, which reduces the side reactions of SL with lithium metal, prevents the growth of lithium dendrites, and suppresses the increase in cell impedance over long-term cycling. Our findings demonstrate that polar and porous separators could effectively improve the affinity to the concentrated electrolytes and allow the formation of the anion-derived SEI layer by increasing the salt concentration of the electrolytes, achieving the long-term stable lithium metal anode.

A new concept, "radical-controlled" oxidative polymerization of phenols catalyzed by a tyrosinase model complex, has been proposed. A µ-η 2 :η 2 -peroxo dicopper(II) species formed by the reaction between the catalyst complex and dioxygen, reacted with phenol to give "controlled" phenoxy radicalcopper(I) intermediate instead of "free" phenoxy radical. The polymerization of 4-phenoxyphenol was performed by the use of the tyrosinase model complexes, (hydrotris(3,5-diphenyl-1-pyrazolyl)borate)copper (Cu(Tpzb)) chloride complex and (1,4,7-R 3-1,4,7-triazacyclononane)copper (Cu(L R ): R ) isopropyl (iPr), cyclohexyl (cHex), n-butyl (nBu)) dichloride complexes. The structures of these complexes were determined by X-ray crystallography, indicating that the order of steric repulsion of the substituents (R) in the Cu(L R ) complexes is cHex > iPr > nBu. Very little of C-C coupling dimers were afforded with the Cu(Tpzb) catalyst in toluene or THF, and with the Cu(L iPr ), Cu(L cHex ), or Cu(L nBu ) catalyst in toluene. The selectivity of para C-O coupling increased with an increase in the steric hindrance of R for the Cu(L R ) catalysts. On the other hand, the formation of C-C dimers was clearly observed in the polymerization catalyzed by a copper/diamine complex or horseradish peroxidase. The selective polymerization almost without the C-C dimer formation produced crystalline poly(1,4-phenylene oxide) having a melting point, although the polymer contained small amounts of 1,2,4-trioxybenzene units (ca. 1-5 unit %). However, the polymers obtained in the cases involving the C-C dimer formation showed no clear melting points. The reaction mechanism of catalytic cycle and oxidative polymerization is also discussed.

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