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In an interlayered carbon fiber-reinforced polycarbonate polymer (CFRPC) composite composed of three sized of CF plies, alternating between four PC sheets, designated [PC] 4 [CF] 3 , and a new process of activating CF cross-weave cloth plies directly on both sides with homogeneous low-energy electron beam irradiation (HLEBI) before lamination assembly and hot pressing at 6.0 MPa and 537 K for 8 min was produced. Experimental results show that a dose of 215 kGy of HLEBI raised the bending strength, σ b , at each experimental accumulative probability, P a , with the σ b at a median P a of 0.50, increasing by 25% over that of the untreated sample. Three-parameter Weibull analysis showed that when quality can be controlled, a dose of 215 kGy of HLEBI can raise the statistically lowest bending strength, σ s , at P a = 0 (94.3 Mpa), with a high correlation coefficient. This is because, although it had a higher bending strength than that in the other experimental conditions, the weakest sample of the 215 kGy data set had a much lower σ b value than that of the others. Electron spin resonance (ESR) of the CF showed that naturally occurring dangling bonds in CF were increased at 215 kGy. Charge transfer to the PC occurs, apparently generating stronger bonds, which are possibly covalent, resulting in enhanced adhesion at the CF-PC interface.

The Closterium peracerosum-strigosum-littorale complex (Closterium, Zygnematophyceae) has an isogamous mating system. Members of the Zygnematophyceae are the closest relatives to extant land plants and are distantly related to chlorophytic models, for which a genetic basis of mating type (MT) determination has been reported. We thus investigated MT determination in Closterium. We sequenced genomes representing the two MTs, mt+ and mt-, in Closterium and identified CpMinus1, a gene linked to the mt- phenotype. We analyzed its function using reverse genetics methods. CpMinus1 encodes a divergent RWP-RK domain-containing-like transcription factor and is specifically expressed during gamete differentiation. Introduction of CpMinus1 into an mt+ strain was sufficient to convert it to a phenotypically mt- strain, while CpMinus1-knockout mt- strains were phenotypically mt+. We propose that CpMinus1 is the major MT determinant that acts by evoking the mt- phenotype and suppressing the mt+ phenotype in heterothallic Closterium. CpMinus1 likely evolved independently in the Zygnematophyceae lineage, which lost an egg-sperm anisogamous mating system. mt- specific regions possibly constitute an MT locus flanked by common sequences that undergo some recombination., (© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.)