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Thermoplastic polysiloxane-based polyurethane (Si-TPU) has been attracting a great deal of attention because of the dual advantages of polysiloxane and polyurethane. However, the strength of Si-TPU with a traditional structure is low, and improvement is urgently needed for diverse applications. Herein, we design a polysiloxane-based soft segment (SS) with two urethane groups at the end of the polysiloxane chain, and then we prepare a series of Si-TPUs through a designed SS, isophorone diisocyanate and 1,4-butanediol. Such structural design improves the polarity of the SS and endows more regular hydrogen bonds to the polymer molecular chain. As a result, the prepared Si-TPUs exhibit a good microphase separation structure, unprecedentedly high strength, repeatable processing, noncytotoxicity, shape memory properties, and three-dimensional printing capabilities. Moreover, a maximum tensile strength of Si-TPUs can reach 20.3 MPa, exceeding that of other existing Si-based polymer materials. Si-TPUs show great potential for biomedical applications.

Polylactic acid (PLA) has received increased attention in the development of shape-memory polymers and biomedical materials owing to its excellent physical properties and good biocompatibility and biodegradability. However, the inherent brittleness and high shape-recovery temperature of this material limit its application in the human body. Herein, we fabricated a PLA-based thermoplastic polyurethane (PLA-TPU) prepared from modified PLA-diol, dicyclohexylmethane-4,4'-diisocyanate, and 1,4-butanediol to solve the limitations of pure PLA. The glass transition temperature (

Hybridization is very common in flowering plants and it plays a significant role in plant evolution and adaptation. Melastoma L. (Melastomataceae) comprises about 80–90 species in tropical Asia and Oceania, among which 41 species occur in Borneo. Natural hybridization is frequently reported in Melastoma in China, but so far there have been no confirmed cases of hybridization in Southeast Asia (including Borneo), where most species occur. Here, we identified a case of natural hybridization between Melastoma malabathricum L. and Melastoma beccarianum Cogn. in Sarawak, Malaysia, by using sequence data of three nuclear genes and one chloroplast intergenic spacer. Melastoma malabathricum is the most widespread species of this genus, occurring in almost the whole range of this genus, while M. beccarianum is a local species endemic to northern Borneo. Our results showed that natural hybridization and introgression occur between M. malabathricum and M. beccarianum, and the introgression was asymmetrical, mainly from M. malabathricum to M. beccarianum. As adaptive traits can be transferred by introgression, our study suggests that natural hybridization should be a significant mechanism for the evolution and adaptation of Melastoma in Southeast Asia. However, introgression from the common species M. malabathricum to the relatively rare species M. beccarianum may cause the decline of M. beccarianum, incurring conservation concern. With a large number of species of Melastoma and almost year‐around flowering in Southeast Asia, more cases of natural hybridization are expected to be found and identified in near future.

Premise of the study: To examine patterns of genetic diversity and test possible hybridization events, microsatellite markers were identified and characterized in Hoya ledongensis (Apocynaceae), and cross-amplification was tested in a congener, H. jianfenglingensis. Methods and Results: Based on the transcriptome data of H. ledongensis, 46 microsatellite primer pairs were randomly selected for initial validation. From these, 28 primer pairs were successfully amplified, 12 of which were polymorphic in 36 individuals across three populations of H. ledongensis. The number of alleles per microsatellite locus ranged from two to 11. The observed and expected heterozygosities for the 12 loci ranged from 0.133 to 0.867 and 0.128 to 0.894, respectively. Cross-species amplification was successful for these 12 loci in the congeneric species H. jianfenglingensis. Conclusions: These polymorphic transcriptome-derived simple sequence repeat markers have the potential to be used as multilocus molecular markers to study the population genetics and natural hybridization in species of Hoya.