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Chiral nematic mesoporous phenol‐formaldehyde resins, which were prepared using cellulose nanocrystals as a template, can be used as a substrate to produce latent photonic images. These resins undergo swelling, which changes their reflected color. By writing on the films with chemical inks, the density of methylol groups in the resin changes, subsequently affecting their degree of swelling and, consequently, their color. Writing on the films gives latent images that are revealed only upon swelling of the films. Using inkjet printing, it is possible to make higher resolution photonic patterns both as text and images that can be visualized by swelling and erased by drying. This novel approach to printing photonic patterns in resin films may be applied to anti‐counterfeit tags, signage, and decorative applications.  相似文献   
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Recently a great interest in the field of protein engineering and the design of innovative drug delivery systems employing specific ligands such as cyclodextrins is observed. The paper reports the solid state, thermal method for protein coupling with β-cyclodextrin and the physicochemical and biological properties of the obtained conjugates. The structure of the obtained conjugates was investigated via liquid chromatography-mass spectrometry, dynamic light scattering and circular dichroism analysis. The presented conjugates were biologically active and covalently bound β-cyclodextrin preserved the ability to form inclusion complexes with the model compound. This report demonstrates the great potential of cyclodextrin as a modifying unit that can be used to modulate the properties of therapeutic proteins, additionally giving such conjugates the possibility to transport many therapeutic substances in the form of inclusion complexes. In addition, the paper presents the potential of protein-cyclodextrin conjugates to construct innovative bioactive molecules for biological and medical applications.  相似文献   
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This study describes the influence of melamine polyphosphate (MPP) flame retardant addition on layered structure of virgin sodium montmorillonite (MMT) in PA6/MMT system obtained in extrusion process. It was found that the extrusion of the PA6/MMT binary system in co‐rotating twin screw extruder gives intercalated clay nanocomposites, while during extrusion of ternary PA6/MMT/MPP composite, full exfoliation of clay was obtained in the system. Structure of the composites was proved utilizing wide angle X‐ray scattering and transmission electron microscopy techniques. Exfoliation of MMT in ternary PA6/MMT/MPP system was also confirmed by rheological studies (viscosity and creep measurements) which were carried out using rotational rheometer. Young's modulus of PA6/MMT/MPP was found to be ~25% greater comparing to PA6/MPP of the same filling level. Cone calorimetry experiments proved decrease of heat release rate peak of PA6/MMT/MPP by ~55% comparing to PA6/MPP with the same total filling level. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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Secondary metabolome mining efforts in the myxobacterial multiproducer of natural products, Chondromyces crocatus Cm c5, resulted in the isolation and structure elucidation of crocagins, which are novel polycyclic peptides containing a tetrahydropyrrolo[2,3-b]indole core. The gene cluster was identified through an approach combining genome analysis, targeted gene inactivation in the producer, and in vitro experiments. Based on our findings, we developed a biosynthetic scheme for crocagin biosynthesis. These natural products are formed from the three C-terminal amino acids of a precursor peptide and thus belong to a novel class of ribosomally synthesized and post-translationally modified peptides (RiPPs). We demonstrate that crocagin A binds to the carbon storage regulator protein CsrA, thereby inhibiting the ability of CsrA to bind to its cognate RNA target.  相似文献   
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