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Spider silks are among the toughest known materials and thus provide models for renewable, biodegradable, and sustainable biopolymers. However, the entirety of their diversity still remains elusive, and silks that exceed the performance limits of industrial fibers are constantly being found. We obtained transcriptome assemblies from 1098 species of spiders to comprehensively catalog silk gene sequences and measured the mechanical, thermal, structural, and hydration properties of the dragline silks of 446 species. The combination of these silk protein genotype-phenotype data revealed essential contributions of multicomponent structures with major ampullate spidroin 1 to 3 paralogs in high-performance dragline silks and numerous amino acid motifs contributing to each of the measured properties. We hope that our global sampling, comprehensive testing, integrated analysis, and open data will provide a solid starting point for future biomaterial designs., クモ糸の構造と力学物性をデータベース化 --人工クモ糸材料の創出に貢献--. 京都大学プレスリリース. 2022-10-13.

Maturation provides whisky with a mild and smooth texture by removing the irritating alcoholic flavor. However, the precise mechanism by which the whisky flavor is improved through the maturation process remains unknown. In this study, we performed mesoscopic structural measurements—dynamic light scattering (DLS) and small‐angle X‐ray scattering (SAXS)—to elucidate the relationship between the liquid structure and flavor maturation of whiskies. Both techniques detected two scattering components corresponding to the clusters formed by the extractives from oak casks during maturation, which are not present in the new make (freshly distilled whisky). Analyzing the scattering profiles revealed that only the small clusters increase in concentration during maturation. It is concluded the small cluster component is crucial for obtaining flavorful whiskies, while the large cluster component, whose concentration is independent of the maturation time, is related to the alcoholic irritation of the whiskies, as demonstrated by the sonication test.

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Precisely tuned functional coordination nanosheet exhibits competent catalytic activity for HER, accompany with drastic electronic property switching by redox treatment., A π-conjugated coordination nanosheet comprising bis(aminothiolato)nickel (NiAT) moieties was synthesized by the reaction of Ni(acac)2 with 1,3,5-triaminobenzene-2,4,6-trithiol at liquid–liquid and gas–liquid interfaces. The sheet thickness could be controlled down to a single layer (0.6 nm). Selected area electron diffraction and grazing incidence X-ray diffraction analyses indicated the formation of a flat crystalline sheet with a kagome lattice stacked in a staggered alignment. NiAT was reversibly interconverted to a bis(iminothiolato)nickel (NiIT) nanosheet by the chemical 2H+–2e– reaction, which was accompanied by a drastic change in electrical conductivity from 3 × 10–6 to 1 × 10–1 S cm–1. This change in conductivity was explained by the difference in band structures between NiAT and NiIT. NiAT acted as an efficient electrocatalyst for the hydrogen evolution reaction, showing strong acid durability and an onset overpotential of –0.15 V.

To investigate a hybrid of isoindigo and thienoisoindigo (TIIG), a new series of unsymmetrical TIIG analogs, in which one of the outer thiophene rings of TIIG is replaced by benzene (CS) or pyridine (NS) are prepared. In addition, the π-skeleton extension effects are studied by examining α-substituted TIIG derivatives with thienyl (Dth-TIIG), furyl (Dfu-TIIG), and 1-phenyl-5-pyrazolyl groups (Bis(1-ph-5-py)-TIIG). These materials exhibit ambipolar transistor properties as expected from the energy levels. Dth-TIIG and Dfu-TIIG show hole mobilities exceeding 0.05 cm2 V−1 s−1, and electron mobilities about 0.04 cm2 V−1 s−1, which are close to those of the diphenyl derivative. These molecules are arranged nearly perpendicularly to the substrates in the thin films, and Dth-TIIG has a brickwork-like structure, whereas Dfu-TIIG has uniform columns. CS and Bis(1-ph-5-py)-TIIG have uniform stacking structures, but NS has a dimerized stacking structure due to the slightly bent molecular plane that results from largely unbalanced electron density.

In X-ray experimental stations at SPring-8, beamline staff and experimental users sometimes need to reconfigure the measurement system for new experiments. Quick reconfiguration for the system is required and this resulted in elaborated work. Aim of DARUMA is to provide standardized procedure for constructing a flexible system of the data collection and control system for experimental stations. It utilizes the control framework MADOCA II* developed for the distributed control of accelerators and beamlines at SPring-8. Unified control procedure with abstracted text-based messaging helps to reduce significant time and cost for preparing the measurement system. DARUMA provides the applications for 2D detectors such as PILATUS, pulse motor and trigger system used in stations. Image data are collected with metadata into NoSQL database, Elasticsearch. Analysis tools for image such as online monitoring and offline analysis are also provided. User applications can be easily developed with Python and LabVIEW. DARUMA can be flexibly applied to experimental stations and is being implemented into BL03XU at SPring-8. We are also planning to introduce it into other experimental stations., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

As one of the most effective molecular design strategies in organic electronics, heteroatom substitution was employed for the first time to study the acceptor variation effects on the optical, electrochemical, molecular assembling, and charge-transport properties of novel semiconducting polymers containing benzobisthiadiazole (BBT)-related heterocycles, namely, poly(dithiazolfluorene-alt-thiadiazolobenzotriazole) (PSN), poly(dithiazolfluorene-alt-selenadiazolobenzotriazole) (PSeN), and poly(dithiazolfluorene-alt-selenadiazolobenzothiadiazole) (PSeS). The effect of the heteroatom substitution was clearly shown in the UV–vis–NIR absorption spectra in which the substitution of the sulfur (S) and/or nitrogen (N) atoms in PSN with the selenium (Se) and sulfur (S) atoms led to a red-shift in the absorption profile. In addition, the energy levels of these polymers, determined from cyclic voltammetry (CV) measurements and density functional theory (DFT) calculations, also varied due to the hetroatom substitution ...

論文(Article), Protein adsorption was performed by a polymer brush prepd. by atom-transfer radical polymn. (ATRP) to a porous inorg. membrane. The porous inorg. membrane, Shirasu Porous Glass made from silica, was modified with a halogen-contg. compd. to bind the active species for the polymn. Glycidyl methacrylate was polymd. from the halogen compd. by ATRP for a prescribed time, and subsequently chem. modified. The progression of the chem. modification allowed the membrane to lower the phosphate-buffer flux of the porous membrane due to the attachment of the polymer brush. Bovine serum albumin (BSA), as a model protein, was adsorbed at 12 mg per g of the membrane in permeating BSA soln. through the polymer-brush-attached porous membrane.