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Various beta-glycosyl azides have been synthesized directly in water by the reaction of unprotected sugars and sodium azide mediated by 2-chloro-1,3-dimethylimidazolinium chloride (DMC).

We report on sub-diffraction-limit (SDL) micro/nanofabrication via two-photon-absorption (TPA) photopolymerization. SDL spatial resolution was found possible in a threshold system, where materials responded to light excitation with a pronounced threshold behavior. The diffraction limit in this case became just a measure of focal spot size, but did not put any actual restraint to voxel dimensions. Experimentally, lateral spatial resolution down to 120 nm was realized by using high numerical-aperture optics. In addition, we proposed a profile scanning method, by which the fabrication efficiency was significantly increased. The TPA processing time, in the example given here, was reduced by 90%.

We demonstrate aberration correction in two‐photon microscopy. Specimen‐induced aberrations were measured with a modal wavefront sensor, implemented using a ferro‐electric liquid crystal spatial light modulator (FLCSLM). Wavefront correction was performed using the same FLCSLM. Axial scanned (xz) images of fluorescently labelled polystyrene beads using an oil immersion lens show restored sectioning ability at a depth of 28 µm in an aqueous specimen.

Sugar oxazoline derivatives were directly synthesized from the corresponding N-acetyl-2-amino sugars in aqueous media by using a chloroformamidinium-type dehydrating reagent. The present method could successfully be applied to chito-oligosaccharides, saccharides with acid functions, and a complex-type oligosaccharide derived from a glycopeptide.

We used a photopolymer consisting of urethane acrylate monomer and free-radical-type initiators as a media for recording two-photon-excited ͑TPE͒ focal spots in three dimensions. Mathematically, the initiator plays a role of ''kͱ '' operator, transforming the quadratic light intensity distribution to a linear radical concentration distribution. Then, the monomer acts as a three-dimensional ͑3D͒ ''film,'' fixing the focal volume where radical concentration is above a threshold as a voxel. An ascending scan method was utilized to avoid substrate truncation and to achieve isolated complete 3D voxels, from which accurate forms of TPE focus were obtained. The 3D photographing technology led to a clear explanation of the origin of pronounced contradictions in reported spatial resolutions, and would be critical for laser precision microfabrication in various materials.

Background:The degradation pathway of the intestinal mucin by bifidobacteria is poorly understood. Results: A novel ␣-N-acetylgalactosaminidase, NagBb, was identified from Bifidobacterium bifidum JCM 1254. Conclusion: NagBb might be involved in intracellular degradation of Tn antigen (GalNAc␣1-Ser/Thr). Significance: NagBb represents a novel glycoside hydrolase family 129 in the CAZy database.

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