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Simple sequence repeats (SSRs) are one of the most important molecular markers, which are widespread in plants. Bamboos are important forest resources worldwide. Here, the comprehensive identification and comparative analysis of SSRs were performed in three woody and two herbaceous bamboo species. Altogether 567,175 perfect SSRs and 71,141 compound SSRs were identified from 5737.8 Mb genome sequences of five bamboo species. Di-nucleotide SSRs were the most predominant type, with an average of ~50,152.2 per species. Most SSRs were located in intergenic regions, while those located in genic regions were relatively less. Moreover, the results of annotation distribution indicated that terms with P450, peroxidase and ATP-binding cassette transporter related to lignin biosynthesis might play important roles in woody and herbaceous bamboos under the mediation of SSRs. Furthermore, the peroxidase gene family consisted of a large number of genes containing SSRs was selected for the evolutionary relationship analysis and SSR markers development. Fifteen SSR markers derived from peroxidase family genes of Phyllostachys edulis were identified as polymorphic in 34 accessions belonging to seven genera in Bambusoideae. These results provided a comprehensive insight of SSR markers into bamboo genomes, which would facilitate bamboo research related to comparative genomics, evolution and marker-assisted selection.

Dimethyl formamide (DMF) and dimethyl acetamide (DMAc) have been used as solvents for segmented poly (urethane-urea) (SPUD) fibers in the dry spinning process. In order to simulate the dry spinning process, it is necessary to know the diffusion coefficient of the solvent-polymer system under practical dry spinning conditions. The liquid-liquid diffusion coefficient of DMF-SPUU measured by a Moire pattern method has been reported by Ohzawa et al. The authors have not been able to find any other reported measurements of solvent diffusion coefficients for SPUU. The diffusion coefficients obtained from the Moire pattern, however, do not apply to the whole dry spinning process ranging from the liquid state to the solid state. Thus, in this work, the solid state diffusion coefficients for the DMF-SPUU and the DMAc-SPUU systems were measured with a new apparatus (Film method).This new apparatus uses a quartz-spring to perform vapor sorption experiments to measure the diffusion coefficients. Arrhenius type equation was used to describe the relationship between the temperature and diffusion coefficient for the DMF and DMAc solvents in SPUU.This paper discusses the differences between the temperature dependences in diffusion coefficients of DMF and DMAc, and the difference between the diffusion coefficients measured by the Moire pattern and Film methods. The diffusion coefficients of solvents in the solid state obtained by the Film method are roughly one-tenth of those in the liquid state obtained by the Moire pattern method. The diffusion coefficient of DMAc is roughly equal to that of DMF.