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Background and Aims The dynamics of genome evolution caused by whole genome duplications and other processes are hypothesized to shape the diversification of plants and thus contribute to the astonishing variation in species richness among the main lineages of land plants. Ferns, the second most species-rich lineage of land plants, are highly suitable to test this hypothesis because of several unique features that distinguish fern genomes from those of seed plants. In this study, we tested the hypothesis that genome diversity and disparity shape fern species diversity by recording several parameters related to genome size and chromosome number. Methods We conducted de novo measurement of DNA C-values across the fern phylogeny to reconstruct the phylogenetic history of the genome space occupation in ferns by integrating genomic parameters such as genome size, chromosome number and average DNA amount per chromosome into a time-scaled phylogenetic framework. Using phylogenetic generalized least square methods, we determined correlations between chromosome number and genome size, species diversity and evolutionary rates of their transformation. Key Results The measurements of DNA C-values for 233 species more than doubled the taxon coverage from ~2.2 % in previous studies to 5.3 % of extant diversity. The dataset not only documented substantial differences in the accumulation of genomic diversity and disparity among the major lineages of ferns but also supported the predicted correlation between species diversity and the dynamics of genome evolution. Conclusions Our results demonstrated substantial genome disparity among different groups of ferns and supported the prediction that alterations of reproductive modes alter trends of genome evolution. Finally, we recovered evidence for a close link between the dynamics of genome evolution and species diversity in ferns for the first time.

Two new fern species, Polystichum dongchuanense and P. menglaense (Dryopteridaceae), are described and illustrated from Yunnan, China. Both are members of P. subg. Haplopolystichum sect. Haplopolystichum. Polystichum dongchuanense is most similar to P. acutidens in plant size and pinna size, but the two can be distinguished from each other by pinna serration and soral number on pinnae. Polystichum menglaense is most similar to P. deltodon in plant size, but the two are different in pinna shape and soral distribution. Both new species have extremely narrow distributions and are classified as Critically Endangered (CR) following IUCN Red List Criteria.

A taxonomic revision of Didymochlaena (Didymochlaenaceae) from Asia and the Pacific region is conducted based on morphological and molecular evidence. Seven species are recognized, of which four are described as new and a new status is raised to a species from a variety. These four new species include D. fijiensis from Fiji, D. philippensis from the Philippines, D. punctata from Indonesia, Malaysia, and Thailand, and D. solomonensis from the Solomon Islands. The new status is D. oceanica from Papua New Guinea. Six of the seven species have all been erroneously treated as D. truncatula by earlier pteridologists. A key to the species is provided and descriptions of all species are given.

A new fern species, Leptochilus gracilis, is described and illustrated from southeastern Yunnan, China. Leptochilus gracilis is most similar to L. ellipticus. Compared with L. ellipticus, L. gracilis has a smaller habit with fronds less than 20 cm long, laminae with only one or two pairs of lobes, and midrib of lobes at angles of 45–60 degree with rachis. In contrast, L. ellipticus has a larger habit with fronds more than 30 cm long, laminae with (3–)4–9 pairs of lobes, and midrib of lobes at angles ca. 80–90 degree with rachis. A phylogenetic analysis based on four plastid markers confirmed the recognition of the new species and resulted in an isolated subclade of L. ellipticus clade.

A new fern of Polystichum (Dryopteridaceae), P. asia-minoris, is described and illustrated from Horma Canyon in the borders of Küre Mountains National Park in Kastamonu Province located in the north of Turkey. Polystichum asia-minoris is distinguishable from the morphologically similar P. obliquum by having pinnae abaxially densely covered with broad-type microscales. It is not certain to which lineage the new species closely allied. The new species has extremely narrow distribution and is classified as Critically Endangered (CR) following IUCN Red List Criteria.

Bolbitis is a pantropical fern genus of Dryopteridaceae with ca. 80 species mainly in tropical Asia. Earlier studies confirmed the monophyly of Bolbitis when Mickelia is excluded and identified three major clades in Bolbitis. However, earlier studies are based on relatively small sampling and the majority of Asian species are not sampled. In this study, DNA sequences of three plastid markers of 169 accessions representing ca. 68 (85 % of total) species of Bolbitis in nine out of the 10 series recognized by Hennipman (1977), and 54 accessions representing the five remaining bolbitidoid genera are used to infer a global phylogeny with a focus on Asian species. The major results include: (1) Bolbitis is strongly supported as monophyletic; (2) species of Bolbitis are resolved into four major clades and their relationships are: the Malagasy/Mascarene clade is sister to the rest, followed by the African clade which is sister to the American clade + the Asian clade; (3) six well-supported subclades are identified in the most speciose Asian clade; (4) the free-veined Egenolfia is embedded in Bolbitis and is paraphyletic in relation to species with anastomosing venation; (5) three series sensu Hennipman (1977), B. ser. Alienae, B. ser. Egenolfianae, and B. ser. Heteroclitae, are paraphyletic or polyphyletic; (6) evolution of six morphological characters is analyzed and free venation is found to have evolved from anastomosing venation and reversed to free venation in Bolbitis; and (7) biogeographical implications are drawn and it is shown that a single recent dispersal from Asia resulted in continental disjunction of closely related ferns of Bolbitis between Africa and America.

The fern genus Pseudocyclosorus (Thelypteridaceae) from China and the Pan-Himalaya region is revised based on morphological study. Reduced basal pinnae, angles between costule and costae, and glands/hairs on abaxial surfaces/indusia are considered as the most diagnostic morphological characters for species delimitation. Genus Trigonospora was excluded from genus Pseudocyclosorus. This segregation is supported by multiple morphological features. Eight species were recognized here, namely Pseudocyclosorus tylodes, P. pseudofalcilobus, P. falcilobus, P. subochthodes, P. stramineus, P. ornatipes, P. esquirolii and P. canus. Twenty-one names were reduced as new synonyms. One name (P. duclouxii) was considered a dubious species. A key to these eight species, their descriptions, spore morphology and distribution map of each species are given. Pseudocyclosorus stramineus was a long overlooked species, which has always been misidentified as other similar species, and was wrongly reduced as a synonym of P. duclouxii. Here based on morphology characters, the identity of P. stramineus as a species was reclaimed. A more detailed description with photographs and illustrations, and its whole distribution range are given here.

Our understanding of the flora of China has greatly improved during the last 100 years but effective management of the rich biodiversity and unique natural resources requires resolving the taxonomic limitations of existing treatments. Here, we focus on the epiphytic genusScleroglossumwith special emphasis on the occurrences in Hainan and Yunnan of mainland China. By combining fieldwork, herbarium studies, and DNA barcoding we test the hypothesis that this genus is represented by more than one species in China. Our integrative results show the Yunnan accessions are distinct from those in Hainan in both phenotypic and genotypic variation. The Yunnan accessions belong toS. pusillum, whereas the Hainan accessions represent a distinct species displaying the morphological characteristics ofS. sulcatum. Genotypic evidence suggests the occurrence of cryptic diversity among accessions with the morphology ofS. sulcatum. In summary, the study contributes to the crucial assessment of the plant diversity in Yunnan and illustrates the importance of integrating collection efforts and DNA barcoding approaches to enable effective assessment of the epiphytic diversity of Yunnan.

Civil engineering structures inevitably suffer from nonstationary ambient excitations in practice, which make conventional damage identification methods relying on the stationary assumption ineffective. This study presents a novel method based on unthresholded assembled recurrence distance matrix (UARDM) and multi-label convolutional neural network (CNN) for structural damage identification under nonstationary excitations. UARDM is a new type of recurrence plot (RP) that is proposed to integrate information of multiple channels and dispense with the artificially selected threshold. It reveals intrinsic dynamic characteristics of the structure using its vibration responses from the perspective of global probabilistic autocorrelation. After that, CNN is applied to automatically extract damage-sensitive features of UARDMs and classify them for the identification of damage cases. Instead of the traditional single-label CNN model that labels each combination of damage location and level as an objective class, the multi-label CNN model is developed to decouple the identification processes of damage locations and levels in order to improve the identification accuracy and computational efficiency. It evaluates the damage level at each location through a sub-branch with an independent set of labels and detects the damage locations by fusing information of all the sub-branches. A comprehensive comparison was conducted among single-label and multi-label CNN models input with raw accelerations, unthresholded multivariate recurrence plots (UMRPs), unthresholded recurrence plots (URPs) and UARDMs through numerical simulation and experimental test. It was demonstrated that the proposed structural damage identification method based on UARDM and multi-label CNN was able to identify multiple damage locations and levels under various stationary and nonstationary excitations with higher accuracy, efficiency and robustness, and even able to detect multiple-damage cases that were not measured beforehand and involved in the training dataset.

Rubus yingjiangensis Huan C. Wang, a new species in Rosaceae from Yunnan, southwest China, is described and illustrated. It resembles R. chaetophorus, but clearly differs from it by lacking glandular hairs, 12–18 cm long leaves cordate-auriculate at the base and abaxially tomentose, with the apex acuminate to long acuminate, hypanthium which is 0.5–0.7 cm in diameter, 0.8–1 cm long sepals, and 0.6–0.8 cm long petals. The names R. mallotifolius and R. sapaensis are treated as taxonomic synonyms of R. nigricaulis, which has almost been overlooked in modern taxonomic literature.

Lepisoroid ferns (tribe Lepisoreae, Polypodiaceae) are arguably one of the most confusing fern groups in Polypodiaceae in terms of delimitation of genera largely because of their simple morphology. Previous molecular studies either had very small taxon sampling of the non-Lepisorus genera and did not well resolve the relationships among these genera, or had a relatively large sampling at species level but the critical species were missing or their relationships were not well resolved. A recent study resolved the newly sampled Lepisorus jakonensis as sister to the remaining genera in Lepisoreae excluding Paragramma, and the authors lumped all the six well recognized genera into Lepisorus. In the present study, to infer a phylogeny we used DNA sequences of five plastid markers (matK, rbcL, rbcL-atpB, rps4rps4-trnS, trnLtrnL-F) of 172 accessions representing ca. 44 species of non-Lepisorus genera and 54 accessions representing ca. 50 species of Lepisorus as ingroup, and 10 non-Lepisoreae accessions from the most closely related four genera (Leptochilus, Microsorum, Phymatosorus, and Goniophlebium) in Microsoroideae and one genus (Pyrrosia) in Platycerioideae. Our major results include: (1) All seven currently defined genera except Lepisorus in Lepisoreae are confirmed to be monophyletic; (2) The Lepisorus jakonensis clade is confirmed to be the second earliest diverged lineage in Lepisoreae; (3) Neolepisorus is resolved as sister to the rest in a clade containing all non-Lepisorus genera except Paragramma; (4) Lemmaphyllum is sister to a clade containing Lepidomicrosorium, Neocheiropteris, and Tricholepidium; and (5) Ellipinema gen. nov. is segregated from Lepisorus based on the phylogeny and morphology in order to stabilize the current usage of the existing six non-Lepisorus genera and species names in these genera. A key to all eight genera of Lepisoreae is provided.

Objective To investigate protective effects of puerarin on the human bronchial epithelial (BEAS-2B) cell line against apoptosis caused by gunpowder smog and its mechanisms. Methods BEAS-2B cells cultured in vitro were randomly divided into control group, smog group (the group treated with 4g gunpowder smog for 10min), and smog + puerarin group [puerarin group, the cells were pre-incubated with various concentrations of puerarin (12.5, 25.0, 50.0, 100.0µg/ml) and then exposed to smoke]. Puerarin was added into the cells after innoculation for 12h and then the cells were sequentially cultured for 24h and followed by exposure to smoke for 10min. After being cultured again for 2h, the smoked cells were examined for cell viability using Cell Counting Kit-8(CCK-8), cell apoptosis was observed using Hoechst33258 nucleus staining, and positive rates of Annexin V-PI staining cells and caspase-3 were determined with flow cytometer. Resu lts Compared with control, treatment of BEAS-2B cells with 4g gunpowder smog induced a characteristic apoptotic cell death (P

Three indophenol blue methods have been used to analyze ammounium-N in five typical soils in China. Method I and II, using the same catalyst of sodium nitroprusside but different quantity and types of reagents, are suggested by Soil Science Society of America (SSSA) and Soil Science Society of China (SSSC), respectively. Method III adopts acetone as the catalyst. It was shown that three methods yielded similar ammonium-N contents with each type of soil. But the use of sodium nitroprusside resulted in higher experimental sensitivity; and Method II by SSSC was recommended due to its lower cost.