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A magnetic sheet made of Fe–Si–Al flakes was found to have excellent permeability and electromagnetic-interferences characteristics in a quasimicrowave band. The flakes prepared by attrition were embedded in a polymer with their planes lying parallel to the sheet plane. This sheet exhibits a peculiar dual dispersion in permeability. The Curie temperature of the flakes increases with increasing specific surface area of the flakes. This suggests the composition of the flakes changes to excess Fe by oxidation of Si and Al. This deviation from the Sendust composition brings an increase of a magnetoelastic effect and the dual frequency dispersion seems to be associated with stress caused by attrition. On the basis of these results, flakes with more desirable permeability characteristics were produced from raw powder with less Fe content. Consequently, we could fabricate a magnetic composite that possesses superior noise suppressing effect in a quasi-microwave band.

Saccharomyces cerevisiae normally cannot assimilate mannitol, a promising brown macroalgal carbon source for bioethanol production. The molecular basis of this inability remains unknown. We found that cells capable of assimilating mannitol arose spontaneously from wild-type S. cerevisiae during prolonged culture in mannitol-containing medium. Based on microarray data, complementation analysis, and cell growth data, we demonstrated that acquisition of mannitol-assimilating ability was due to spontaneous mutations in the genes encoding Tup1 or Cyc8, which constitute a general corepressor complex that regulates many kinds of genes. We also showed that an S. cerevisiae strain carrying a mutant allele of CYC8 exhibited superior salt tolerance relative to other ethanologenic microorganisms; this characteristic would be highly beneficial for the production of bioethanol from marine biomass. Thus, we succeeded in conferring the ability to assimilate mannitol on S. cerevisiae through dysfunction of Tup1-Cyc8, facilitating production of ethanol from mannitol. Macroalgae, consisting of green, red, and brown algae, are promising sources of biofuels for several reasons: (i) macroalgae are more productive than land crops; (ii) arable land is not required for algal cultivation, obviating the necessity for irrigation, fertilizer, etc.; and (iii) macroalgae contain no lignin (1-4). Both red and brown algae contain high levels of carbohydrates, and a method for producing biofuel from these carbohydrates would be of tremendous economic and environmental benefit.Brown macroalgae contain up to 33% (wt/wt [dry weight]) mannitol, which is the sugar alcohol corresponding to mannose and a promising carbon source for bioethanol production (1, 5, 6). Although some bacteria, such as Escherichia coli and Zymobacter palmae, can assimilate mannitol, i.e., utilize mannitol and produce ethanol (6, 7), bacteria are generally sensitive to ethanol, as well as, several other growth-inhibitory compounds. Z. palmae and E. coli KO11 can produce ca. 1.3% (wt/vol) and 2.6% (wt/vol) ethanol from 3.8% (wt/vol) and 9.0% (wt/vol) mannitol, respectively; however, both strains are sensitive to 5% (wt/vol) ethanol (8,9). Yeast is currently considered to have several advantages over ethanologenic bacteria, including high tolerance to ethanol and inhibitory compounds (10). Several yeast strains, such as Pichia angophorae and Saccharomyces paradoxus NBRC0259-3, can produce ethanol from mannitol (8, 11). However, compared to the well-characterized model organism Saccharomyces cerevisiae, the host-vector systems of these yeasts are not well equipped, and their genetics and physiologies are poorly defined.Mannitol dehydrogenase is the key enzyme that catalyzes the pyridine nucleotide-dependent oxidation of D-mannitol to Dfructose (12). Despite the existence of genes encoding putative homologs of mannitol dehydrogenase (YEL070W and YNR073C), S. cerevisiae strains, including the S288C reference strain, are unable to assimilate mannitol for growth; a few exceptions exi...

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