: Permanent waving is important process to set hair configuration for the maintenance of wanted hairstyle. This process consists of scission of disulfide (SS) cross-links in hair keratin by reduction, washing with water to remove reductants, and subsequent reformation by oxidation. It is important to assess the type, number and location of SS crosslinks to understand setting mechanism which has been still unknown. Even though the reduction of SS bonds with thiol is equilibrium reaction, there are few researches focusing on washing step which may decrease drastically the concentration of reductants inside or on the surface of the hair fiber. In a permanent waving system consisting of three step processes of reduction with thioglycolic acid (TGA), washing with water and oxidation by sodium bromate, we attempted to quantify the amount of reformation of SS cross-links during washing, and clarify the effect of washing time on the reproduction of the SS cross-links in microstructures of hair. In order to estimate the change in the cross-link density of hair, the force-extension curve for rubber-like swollen hair fibers treated in a specific diluents mixture was analyzed by using a rubber elasticity theory derived from a two-phase model comprising of the globular matrix of keratin-associated proteins (KAP) dispersed in a swollen network of the intermediate filament (IF) proteins. It was found that the integrity of the SS cross-linked structure of IF is retained, while the intermolecular SS cross-links between KAP molecules cleaved by the reduction are regenerated by the reverse reaction of the equilibrium reactions occurring during washing, and this leads to increase of the extension modulus and breaking stress of the hair fibers in water.

Non-negative matrix factorization (NMF) has been frequently used in research on live cells, biomolecules, and tissues (bio-Raman research) to disentangle the complicated and large sized data. A stagnation is that NMF does not provide unique decomposition, depending on initial settings; that is, NMF returns non-negative spectral components close to the truths, but solely giving several possibilities. In this research, we visualized possible ranges of NMF in binary component system. The mechanism of NMF became more clarified and opened new viewpoints.

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<p style="text-align: justify;">Le butanol-2, présent dans les eaux-de-vie de vin de qualité médiocre, est dosé par chromatographie en phase gazeuse. Cet alcool pourrait provenir de la dégradation du butanediol-2,3 par les bactéries lactiques dans les lies de vin.</p><p style="text-align: justify;">80 souches bactériennes ont été étudiées en milieu synthétique sucré et dans du vin, à différents pH et en présence de doses variables de butanediol-2,3 ; trois souches seulement forment du butanol-2 à des doses pouvant atteindre 528 mg par litre en milieu synthétique et une seule souche dans le vin à pH 4,5.</p><p style="text-align: justify;">+++</p><p style="text-align: justify;">The concentration of butanol-2 present in brandies of mediocre quality was determined by gas chromatography. This alcohol may result from the decomposition of butanediol-2,3 by lactic bacteria in wine lees.</p><p style="text-align: justify;">Eighty bacterial strains were studied in a sugared synthetic medium and in wines, at varying levels of pH and concentrations of butanediol-2,3.</p><p style="text-align: justify;">Only three strains formed butanediol-2,3 up to a maximum level of 528 mg per liter in the synthetic medium and one, to the same level, in wine with a pH raised to 4,5.</p>