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Intracellular gene transfer is widely recognized as one of the most important driving forces for species evolution. Here we investigated transferred cytoplasmic motifs in green plants including spore-bearing plants and seed-bearing plants (hereafter termed spore plants and seed plants). Our analyses revealed that gene transfer in spore plants was characterized by shorter motifs than that of seed plants. Several spore species did not exhibit intracellular gene transfer. Meanwhile, high frequency transferred tRNA genes were identified with average values of minimum free energy at moderate level. From the chloroplast to the mitochondrial genome, trnP was found to have transferred with high frequency in green plants. In gene transfer from the mitochondrial to the chloroplast genome, trnN was found to be a highly transferred gene. We observed that several tRNA genes including trnF , trnW , and trnN were involved in bidirectional transfer, which may be related to application strategy of functional protein-coding genes in a plant's adaptive evolution. Codon Adaptation Index (CAI) analysis showed that codon usage was unbalanced in spore and seed plants. CAI values for seed plants were higher than those for spore plants in general, which may reveal rapid divergence adaptability of codon usage in the former. These results provide novel insights into gene transfer and codon usage within cytoplasmic genomes. [ABSTRACT FROM AUTHOR]

Cannabaceae are a relatively small family of angiosperms, but they include several species of huge economic and cultural significance: marijuana or hemp (Cannabis sativa) and hops (Humulus lupulus). Previous phylogenetic studies have clarified the most deep relationships in Cannabaceae, but relationships remain ambiguous among several major lineages. Here, we sampled 82 species representing all genera of Cannabaceae and utilized a new dataset of 90 nuclear genes and 82 chloroplast loci from Hyb‐Seq to investigate the phylogenomics of Cannabaceae. Nuclear phylogenetic analyses revealed a robust and consistent backbone for Cannabaceae. We observed nuclear gene‐tree conflict at several deep nodes in inferred species trees, also cyto‐nuclear discordance concerning the relationship between Gironniera and Lozanella and the relationships among Trema s.l. (including Parasponia), Cannabis + Humulus, and Chaetachme + Pteroceltis. Coalescent simulations and network analyses suggest that observed deep cyto‐nuclear discordances were most likely to stem from incomplete lineage sorting (ILS); nuclear gene‐tree conflict might be caused by both ILS and gene flow between species. All genera of Cannabaceae were recovered as monophyletic, except for Celtis, which consisted of two distinct clades: Celtis I (including most Celtis species) and Celtis II (including Celtis gomphophylla and Celtis schippii). We suggest that Celtis II should be recognized as the independent genus Sparrea based on both molecular and morphological evidence. Our work provides the most comprehensive and reliable phylogeny to date for Cannabaceae, enabling further exploration of evolutionary patterns across this family and highlighting the necessity of comparing nuclear with chloroplast data to examine the evolutionary history of plant groups. [ABSTRACT FROM AUTHOR]

Gypsophila huashanensis Y. W. Tsui & D. Q. Lu (Caryophyllaceae) is an endemic herb species to the Qinling Mountains in China. In this study, we characterized its whole plastid genome using the Illumina sequencing platform. The complete plastid genome of G. huashanensis is 152,457 bp in length, including a large single-copy DNA region of 83,476 bp, a small single-copy DNA region of 17,345 bp, and a pair of inverted repeat DNA sequences of 25,818 bp. The genome contains 130 genes comprising 85 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Evolutionary analysis showed that the non-coding regions of Caryophyllaceae exhibit a higher level of divergence than the exon regions. Gene site selection analysis suggested that 11 coding protein genes (accD, atpF, ndhA, ndhB, petB, petD, rpoCl, rpoC2, rps16, ycfl, and ycf2) have some sites under protein sequence evolution. Phylogenetic analysis showed that G. huashanensis is most closely related to the congeneric species G. oldhamiana. These results are very useful for studying phylogenetic evolution and species divergence in the family Caryophyllaceae. [ABSTRACT FROM AUTHOR]

A novel structure of dual-composite right/left-handed transmission line (D-CRLH TL) is proposed and analyzed in this paper. The simulated reaults show that there is a stopband between the first right-handed passband and the left-handed passband of the proposed D-CRLH TL. This stopband characteristic is applied to improve the electromagnetic performances of low-pass filter (LPF). A planar compact microstrip LPF with ultra-wide stopband (UWSB) and high selectivity is designed, fabricated and measured. The measured and simulated results are in good agreement with each other, indicating that this design method is effective and successful. The measured results show that the cut-off frequency of the LPF in this paper is 3.68 GHz, the stopband with insertion loss of more than 20 dB is from 3.84GHz to 20.21GHz (136.1%), and the sharpness is 106.25dB/GHz. Compared with the previous works of references, the LPF in this paper has less insertion loss, greater stop-bandwidth and better sharpness. Besides, this LPF also realizes a 73% size reduction in comparison with the same work in reference [14].

Determining the mechanisms that drive phenotypic and genetic divergence by species has been a central topic in evolutionary biology for many years. However, the relative contributions of isolation by distance (IBD) and environment factors to species divergence are largely unknown in perennial herbs in East Asia. In this study, we collected population genetic samples of the cold‐tolerant perennial herb Notopterygium oviforme R. H. Shan in central China. We integrated the population transcriptomes, whole chloroplast genomes, genotyping‐by‐sequencing, microsatellite markers, and ecological factors to determine the relative contributions of geography, climate, and soil factors to genetic, chemical, and phenotypic divergence. A clear genetic distinction was identified between the West Qinling and East Qinling Mountains geographical groups of N. oviforme based on various molecular datasets. Interestingly, obvious niche conservation might have been responsible for the similarity of most of the leaf functional traits in the two groups. Multiple matrix regression with randomization analysis showed that the spatial intraspecific divergence pattern was mainly due to IBD rather than isolation by environment. In addition, transcriptomic expression divergence and some ecological factors have played key roles in intraspecific lineage differentiation. Approximate Bayesian Computation showed that both lineages have experienced historical population expansion and recent range contraction. Molecular dating suggested that intraspecific divergence was closely associated with dramatic uplifts of the Qinling Mountains in East Asia. These results demonstrate that geographical, geological, and environmental factors together shaped cryptic intraspecific diversification and shifts in the population dynamics of the perennial cold‐tolerant herb N. oviforme. [ABSTRACT FROM AUTHOR]

The paper introduced implementation of an intelligent path detector for electrified cable with AVR single-chip microcomputer as core. The path detector provides two operating modes of specific frequency detection and unknown frequency search for two cases of signal frequency known or unknown respectively, and determines position of the cables according to induced electromotive force generated by the coil, thus realizes detection of underground cable path without affecting normal working of the cable.