A multifunctional nanocarrier with multilayer core-shell architecture was prepared by alkaline coprecipitation of ferric and ferrous ions in the presence of a triblock copolymer, methoxy poly(ethylene glycol)-block-poly(methacrylic acid)-block-poly(glycerol monomethacrylate) (denoted MPEG-b-PMAA-b-PGMA), in aqueous solution. The core of the nanocarrier is a superparamagnetic Fe 3 O 4 nanoparticle, on which the PGMA block of the triblock copolymer is attached. The PMAA block forms the inner shell and the MPEG block forms the outermost shell. The anticancer agent adriamycin (ADR), as a model drug with an amine group and a hydrophobic moiety, was loaded into the nanocarrier at pH 7.4 by combined action of ionic bonding and hydrophobic interaction. The hydrophobic main chain of PMAA and the hydrophobic microenvironment created by MPEG contribute to the hydrophobic interaction. The synergistic effect between the ionic bond and the hydrophobic interaction significantly enhances the loading capacity. At endosomal/lysosomal acidic pH (<5.5), protonation of polycarboxylate anions of PMAA (pK a ¼ 5.6) breaks the ionic bond between the carrier and ADR, leading to the release of ADR because the hydrophobic interaction alone is very weak due to the relatively hydrophilic character of the nanocarrier.

Seeking efficient visible-light-driven photocatalysts for water splitting to produce H 2 has attracted much attention. Chemical doping is an effective strategy to enhance photocatalytic performance. Herein, we reported phosphorus-doped covalent triazine-based frameworks (CTFs) for photocatalytic H 2 evolution. Phosphorus-doped CTFs were fabricated by a facile thermal treatment using easily available red phosphorus as the external phosphorus species. The introduction of phosphorus atoms into the frameworks modified the optical and electronic property of CTFs, thus promoting the generation, separation, and migration of photoinduced electron−hole pairs. Consequently, the photocatalytic H 2 -production efficiency of phosphorus-doped CTFs was greatly improved, which was 4.5, 3.9, and 1.8 times as high as that of undoped CTFs and phosphorusdoped g-C 3 N 4 calcined from melamine and urea, respectively.

Different hypotheses have been proposed to interpret the observed unusual ITS (internal transcribed spacer) sequences in Ophiocordyceps sinensis. The coexistence of diverged ITS paralogs in a single genome was previously shown by amplifying the ITS region from mono-ascospore isolates using specific primers designed for different ITS paralog groups. Among those paralogs, are AT-biased ITS sequences which were hypothesized to result from repeat-induced point mutation (RIP). This is a process that detects and mutates repetitive DNA and frequently leads to epigenetic silencing, and these mutations have been interpreted as pseudogenes. Here we investigate the occurrence and frequency of ITS pseudogenes in populations of O. sinensis using large-scale sampling, and discusses the implications of ITS pseudogenes for fungal phylogenetic and evolutionary studies. Our results demonstrate a wide distribution of ITS pseudogenes amongst different geographic populations, and indicate how ITS pseudogenes can contribute to the reconstruction of the evolutionary history of the species.

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