Physcomitrella patens is an extremely dehydration-tolerant moss. However, the molecular basis of its responses to loss of cellular water remains unclear. A comprehensive proteomic analysis of dehydration- and rehydration-responsive proteins has been conducted using quantitative two-dimensional difference in-gel electrophoresis (2D-DIGE), and traditional 2-D gel electrophoresis (2-DE) combined with MALDI TOF/TOF MS. Of the 216 differentially-expressed protein spots, 112 and 104 were dehydration- and rehydration-responsive proteins, respectively. The functional categories of the most differentially-expressed proteins were seed maturation, defence, protein synthesis and quality control, and energy production. Strikingly, most of the late embryogenesis abundant (LEA) proteins were expressed at a basal level under control conditions and their synthesis was strongly enhanced by dehydration, a pattern that was confirmed by RT-PCR. Actinoporins, phosphatidylethanolamine-binding protein, arabinogalactan protein, and phospholipase are the likely dominant players in the defence system. In addition, 24 proteins of unknown function were identified as novel dehydration- or rehydration-responsive proteins. Our data indicate that Physcomitrella adopts a rapid protein response mechanism to cope with dehydration in its leafy-shoot and basal expression levels of desiccation-tolerant proteins are rapidly upgraded at high levels under stress. This mechanism appears similar to that seen in angiosperm seeds.

In this work, it is demonstrated that random copolymerization is a simple but effective strategy to obtain new conductive copolymers as high‐performance thermoelectric materials. By using a polymerizing acceptor unit diketopyrropyrrole with donor units thienothiophene and oligo ethylene glycol substituted bithiophene (g32T), it is found that strong interchain donor–acceptor interactions ensure good film crystallinity for charge transport, while donor–donor type building blocks contribute to effective charge transfers. Hall effect measurements show that the high electrical conductivity results from increased free carriers with simultaneously improved mobility reaching over 1 cm2 V−1 s−1. The synergistic effect of improved molecular doping and carrier mobility, as well as a high Seebeck coefficient ascribed to the structural disorder along polymer chains via random copolymerization, results in an impressive power factor up to 110 µW K−2 m−1 which is 10 times higher than that of solution‐processed polythiophenes.

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The effect of different iron (III) dopants on the doping process and charge transport properties based on a poly(3hexylthiophene) (P3HT) film was investigated. It is found that the doping level is dependent on not only the driving force for charge transfer but also the miscibility between a polymer and a dopant, while the mobile carrier transport is significantly controlled by the microstructure upon doping. A high electrical conductivity (128 S cm −1 ) is obtained for a FeCl 3 -doped P3HT film among three different doped P3HT combinations, although a low doping level is observed in this film. In contrast, a highest doping level but a low electrical conductivity (65 S cm −1 ) is achieved for Fe(OTf) 3 -doped P3HT. Another ferric salt with a larger size anion and strong oxidation ability, Fe(Tos) 3 , endows both much low doping level and low electrical conductivity (9 S cm −1 ). Grazing-incidence wide-angle X-ray scattering (GIWAXS) shows that a much stronger π−π stacking of P3HT and larger crystalline domains may exist in Fe(OTf) 3 -doped P3HT compared with those of FeCl 3 -doped P3HT. However, Hall-effect measurements show that the high electrical conductivity of FeCl 3 -doped P3HT is mainly attributed to higher carrier mobility. Temperature-dependent conductivity experiments demonstrate that smaller activation energy for carrier transport is needed for a FeCl 3 -doped P3HT film. These results indicate that smooth and continuous transport paths are formed in a FeCl 3doped film, contributing to high carrier mobility while discrete domains in Fe(OTf) 3 -doped film hamper the carrier transport. A prototype device with a five-leg FeCl 3 -doped P3HT film connected with a silver paste was fabricated. The measured maximum output power is about 4.64 nW at the temperature difference of 23.3 K. Our results suggest that the interaction between dopant anions and polymer chains is crucial for high electrical conductivity by improving morphologies to achieve ionized carriers' transfer into much mobile carriers.