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Dryopteris sect. Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia. Here, we carried out morphological and phylogenetic analyses of this section. A new species from southwest China, D. gaoligongensis, is described and illustrated. Dryopteris gaoligongensis resembles D. indonesiana and D. sparsa, but differs by having a creeping rhizome and large 4-pinnate fronds. We also show that D. glabrior Ching & Z.Y. Liu is a distinct species; however, because it is a later homonym of D. glabrior Copeland, it should be renamed D. renchangiana. We conclude that a species previously known as D. nitidula, also an illegitimate homonym, should be recognized with a new name, D. sinonepalensis. We resolve the phylogenetic position of D. yoroii as sister to other sampled species of D. sect. Diclisodon. Our phylogenetic analyses confirm the distinctiveness of D. gaoligongensis, D. renchangiana, and D. sinonepalensis. A key to species of D. sect. Diclisodon in China is provided.

The pollution source identification methods based on traditional water quality monitoring and pollutant discharge loading typically require a high frequency of monitoring and generate a level of uncertainty in the identification results, owing to their limitations on the accurate and quantitative assessment of pollution source identification, migration, and transformation. This study combined multivariate statistical analysis and stable isotope technology to identify groundwater pollution sources in a typical multiple land-use area of the Chengdu Plain. A positive matrix factorization (PMF) model was adopted to reduce the interference of mass environmental factors on source identification and to determine the main factors influencing groundwater quality. Subsequently, a Bayesian stable isotope mixing model was developed to quantify the apportionment of each pollution source to groundwater nitrate (NO

Comprising about 82% of the extant fern species diversity, Polypodiales are generally believed to have diversified in the Late Cretaceous. We estimated the divergence times of Polypodiales using both penalized likelihood and Bayesian methods, based on a dataset consisting of 208 plastomes representing all 28 families and 14 fossil constraints reflecting current interpretations of fossil record. Our plastome phylogeny recovered the same six major lineages as a recent nuclear phylogeny, but the position of Dennstaedtiineae was different. The present phylogeny showed high resolution of relationships among the families of Polypodiales, especially among those forming the Aspleniineae. The divergence time estimates supported the most recent common ancestor of Polypodiales and its closest relative dating back to the Triassic, establishment of the major lineages in the Jurassic, and a likely accelerated radiation during the late Jurassic and the Early Cretaceous. The estimated divergence patterns of Polypodiales and angiosperms converge to a scenario in which their main lineages were established simultaneously shortly before the onset of the Cretaceous Terrestrial Revolution, and further suggest a pre-Cretaceous hidden history for both lineages. The pattern of simultaneous diversifications shown here elucidate an important gap in our understanding of the Terrestrial Revolution that shaped today's ecosystems.

Cytidine-to-uridine (C-to-U) RNA editing is common in coding regions of organellar genomes throughout land plants. In most cases RNA editing alters translated amino acids or creates new start codons, potentially confounds phylogenetic reconstructions. In this study, we used the spike moss genus Selaginella (lycophytes), which has the highest frequency of RNA editing, as a model to test the effects of extreme RNA editing on phylogenetic reconstruction. We predicted the C-to-U RNA editing sites in coding regions of 18 Selaginella plastomes, and reconstructed the phylogenetic relationships within Selaginella based on three data set pairs consisted of plastome or RNA-edited coding sequences, first and second codon positions, and translated amino acid sequences, respectively. We predicted between 400 and 3100 RNA editing sites of 18 Selaginella plastomes. The numbers of RNA editing sites in plastomes were highly correlated with the GC content of first and second codon positions, but not correlated with the GC content of plastomes as a whole. Contrast phylogenetic analyses showed that there were substantial differences (e.g., the placement of clade B in Selaginella) between the phylogenies generated by the plastome and RNA-edited data sets. This empirical study provides evidence that extreme C-to-U RNA editing in the coding regions of organellar genomes alters the sequences used for phylogenetic reconstruction, and might even confound phylogenetic reconstruction. Therefore, RNA editing sites should be corrected when plastid or mitochondrial genes are used for phylogenetic studies, particularly in those lineages with abundant organellar RNA editing sites, such as hornworts, quillworts, spike mosses, and some seed plants.

While roses are today among the most popular ornamental plants, the petals and fruits of some cultivars have flavored foods for millennia. The genetic origins of these edible cultivars remain poorly investigated. We collected the major varieties of edible roses available in China, assembled their plastome sequences, and phased the haplotypes for internal transcribed spacers (ITS1/ITS2) of the 18S-5.8S-26S nuclear ribosomal cistron. Our phylogenetic reconstruction using 88 plastid genomes, of primarily maternal origin, uncovered well-supported genetic relationships within Rosa, including all sections and all subgenera. We phased the ITS sequences to identify potential donor species ancestral to the development of known edible cultivars. The tri-parental Middle-Eastern origin of R. × damascena, the species most widely used in perfume products and food additives, was confirmed as a descendent of past hybridizations among R. moschata, R. gallica, and R. majalis/R. fedtschenkoana/R. davurica. In contrast, R. chinensis, R. rugosa, and R. gallica, in association with six other wild species, were the main donors for fifteen varieties of edible roses. The domesticated R. rugosa ‘Plena’ was shown to be a hybrid between R. rugosa and R. davurica, sharing a common origin with R. ‘Fenghua’. Only R. ‘Jinbian’ and R. ‘Crimson Glory’ featured continuous flowering. All remaining cultivars of edible roses bloomed only once a year. Our study provides important resources for clarifying the origin of edible roses and suggests a future for breeding new cultivars with unique traits, such as continuous flowering.

In this paper, two kinds of coupled fractional-order reaction-diffusion neural networks (CFORDNNs) with multiple state couplings or spatial diffusion couplings are proposed. By resorting to the Laplace transform and the properties of Mittag-Leffler functions, sufficient synchronization conditions are derived for the concerned network models. In addition, to guarantee the synchronization of these two networks, several appropriate adaptive control schemes are also developed. Ultimately, the validity of the devised adaptive strategies are verified by adopting some numerical examples with simulation results.

In the paper, the authors establish an inequality involving exponential functions and sums, introduce a ratio of finitely many gamma functions, discuss properties, including monotonicity, logarithmic convexity, (logarithmically) complete monotonicity, and the Bernstein function property, of the newly introduced ratio, and construct two inequalities of multinomial coefficients and multivariate beta functions.

Neocheiropteris palmatopedata (Baker) Christ is an endangered fern species endemic to southwest China. In this study, we sequenced the complete plastid genome of N. palmatopedata. The gene order and structure of the N. palmatopedata plastome are similar to those published plastomes in Polypodiales. The complete plastome is 153,344 bp in length, and the GC content is 42.1%. The plastome comprises 113 unique genes (83 protein-coding genes, 29 tRNA genes and four rRNA genes).

The rambler Rosa wichuraiana Crép. is an important founder species during modern rose domestication. However, the chloroplast genome (plastome) of this wild species remains unavailable. Here, we assembled the complete chloroplast genomes for two genotypes of R. wichuraiana. Both plastomes were typical quadripartite circular with 156,500/156,504 bp in length, comprising a large single-copy (LSC) region of 85,651/85,660 bp and a small single-copy (SSC) region of 18,751/18,744 bp, separated by two inverted repeat (IR) regions of 26,049/26,050 bp, respectively. Both plastomes encoded 113 unique genes, including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic reconstruction with several rose plastomes revealed that both genotypes were sisters to a clade including Rosa luciae, Rosa multiflora, and Rosa maximowicziana.

In flowering plants, male gametes are delivered to female gametes for double fertilization through pollen tubes. Therefore, pollen tube growth is crucial for double fertilization. Despite its importance to sexual reproduction, genetic mechanisms of pollen tube growth remain poorly understood. In this study, we characterized the receptor-like cytoplasmic protein kinase (RLCK) gene, MARIS (MRI) that plays critical roles in pollen tube growth. MRI is preferentially expressed in pollen grains, pollen tubes and roots. Mutation in MRI by a Ds insertion led to a burst of pollen tubes after pollen germination. Pollen-rescue assay by pollen and pollen tube-specific expression of MRI in the mri-4 mutant showed that loss of MRI function also severely affected root hair elongation. MRI protein interacted with the protein kinase OXIDATIVE SIGNAL INDUCIBLE1 (OXI1) in the in vitro and in vivo assays, which functions in plant defence and root hair development, and was phosphorylated by OXI1 in vitro. Our results suggest that MRI plays important roles in pollen tube growth and may function in root hair elongation through interaction with OXI1.

In this paper, we propose a novel model for the computational color constancy, inspired by the amazing ability of the human vision system (HVS) to perceive the color of objects largely constant as the light source color changes. The proposed model imitates the color processing mechanisms in the specific level of the retina, the first stage of the HVS, from the adaptation emerging in the layers of cone photoreceptors and horizontal cells (HCs) to the color-opponent mechanism and disinhibition effect of the non-classical receptive field in the layer of retinal ganglion cells (RGCs). In particular, HC modulation provides a global color correction with cone-specific lateral gain control, and the following RGCs refine the processing with iterative adaptation until all the three opponent channels reach their stable states (i.e., obtain stable outputs). Instead of explicitly estimating the scene illuminant(s), such as most existing algorithms, our model directly removes the effect of scene illuminant. Evaluations on four commonly used color constancy data sets show that the proposed model produces competitive results in comparison with the state-of-the-art methods for the scenes under either single or multiple illuminants. The results indicate that single opponency, especially the disinhibitory effect emerging in the receptive field's subunit-structured surround of RGCs, plays an important role in removing scene illuminant(s) by inherently distinguishing the spatial structures of surfaces from extensive illuminant(s).

Begonia guangxiensis was assessed as endangered according to Red List of Chinese Plants. In this study, we described the complete plastid genome of B. guangxiensis. The plastid genome sequence of B. guangxiensis is 157,648 bp in size, having a large single-copy region (LSC) of 86,514 bp, a small single-copy region (SSC) of 18,076 bp, and two inverted repeat (IR) regions of 26,529 bp. The complete plastid genome of B. guangxiensis encoding 112 unique genes including 79 protein-coding genes, 29 tRNA genes, and four rRNA genes. The overall GC content of the plastid genome is 35.9%. Phylogenetic analysis confirmed that B. guangxiensis is closely related to B. varipeltata.

Neocheiropteris palmatopedata (Baker) Christ is an endangered fern species endemic to southwest China. In this study, we sequenced the complete plastid genome of N. palmatopedata. The gene order an...

Studies on chloroplast genomes of ferns and lycophytes are relatively few in comparison with those on seed plants. Although a basic phylogenetic framework of extant ferns is available, relationships among a few key nodes remain unresolved or poorly supported. The primary objective of this study is to explore the phylogenetic utility of large chloroplast gene data in resolving difficult deep nodes in ferns. We sequenced the chloroplast genomes from Cyrtomium devexiscapulae (Koidz.) Ching (eupolypod I) and Woodwardia unigemmata (Makino) Nakai (eupolypod II), and constructed the phylogeny of ferns based on both 48 genes and 64 genes. The trees based on 48 genes and 64 genes are identical in topology, differing only in support values for four nodes, three of which showed higher support values for the 48-gene dataset. Equisetum L. was resolved as the sister to the Psilotales-Ophioglossales clade, and Equisetales-Psilotales-Ophioglossales clade was sister to the clade of the leptosporangiate and marattioid ferns. The sister relationship between the tree fern clade and polypods was supported by 82% and 100% bootstrap values in the 64-gene and 48-gene trees, respectively. Within polypod ferns, Pteridaceae was sister to the clade of Dennstaedtiaceae and eupolypods with a high support value, and the relationship of Dennstaedtiaceae-eupolypods was strongly supported. With recent parallel advances in the phylogenetics of ferns using nuclear data, chloroplast phylogenomics shows great potential in providing a framework for testing the impact of reticulate evolution in the early evolution of ferns.

In flowering plants, the male and female gametogenesis is a crucial step of sexual reproduction. Although many genes have been identified as being involved in the gametogenesis process, the genetic mechanisms underlying gametogenesis remains poorly understood. We reported here characterization of the gene, ABORTED GAMETOPHYTE 1 (AOG1) that is newly identified as essential for gametogenesis in Arabidopsis thaliana. AOG1 is expressed predominantly in reproductive tissues including the developing pollen grains and ovules. The AOG1 protein shares no significant amino acid sequence similarity with other documented proteins and is located mainly in nuclei of the cells. Mutation in AOG1 caused degeneration of pollen at the uninucleate microspore stage and severe defect in embryo sacs, leading to a significant reduction in male and female fertility. Furthermore, the molecular analyses showed that the aog1 mutant significantly affected the expression of several genes, which are required for gametogenesis. Our results suggest that AOG1 plays important roles in gametogenesis at the stage prior to pollen mitosis I (PMI) in Arabidopsis, possibly through collaboration with other genes.

This paper mainly designs the outdoor swimming pool circulation purification system, introduced the circulation mode selection, calculation of water cycle, and we proposed water purification treatment measures. After filtration and disinfection of swimming pool water, which achieve the "Hygienic standard for swimming place" (GB9667-1996) that regulations on "the quality and hygiene standards" artificial swimming pool, which can be recycled.

Boehmeria is an important genus; however, no plastid genome has been reported to date. Here we report the complete chloroplast genomes for two Boehmeria species. The chloroplast genomes of Boehmeria umbrosa and Boehmeria spicata were found to be 170920 bp and 170958 in length, respectively, and the GC contents were 35.5 and 35.3%, respectively. The sequences of each species contained 112 unique genes, including 30 tRNA, 4 rRNA, and 78 protein-coding genes. This is the first report of cp genomes for Boehmeria, and will be useful for identifying molecular markers with which to address taxonomic problems in the genus.

Reverse processing parts has many ways, the use of edge detector and CNC machine tools on the part of data measurement, using Bluetooth technology to transfer data, using curve fitting method for data processing is a very practical method of reverse.

In this paper,a kind of 3-UPU spatial parallel mechanism is introduced. Through deep analysis of the degree-of-freedom (DoF) for the platform using screw theory， the position and orientation of the moving platform is discussed. At last, the 3D virtual prototype modeling of this 3-UPU parallel mechanism based on software ADAMS is developed; the kinematics simulation and analysis are also carried out accordingly. From the simulation results, we can see that the proposed calculation of the DoFs and kinematics analysis is correct.

To study the chemical constituents from the leaf of Rhododendron przewalskii.Isolate and purify compounds by chromatographic methods, and identify structures by spectroscopic methods.Six compounds were isolated and identified as hyperin (1), avicularin (2), gossypetin-3-O-β-D-galactoside (3), quercetin (4), betuloside (5) and β-sitosterol (6).Compounds 1-4 and 6 are isolated from Rhododendron przewalskii for the frist time.

In flowering plants, the male and female gametogenesis is a crucial step of sexual reproduction. Although many genes have been identified as being involved in the gametogenesis process, the genetic mechanisms underlying gametogenesis remains poorly understood. We reported here characterization of the gene, ABORTED GAMETOPHYTE 1 (AOG1) that is newly identified as essential for gametogenesis in Arabidopsis thaliana. AOG1 is expressed predominantly in reproductive tissues including the developing pollen grains and ovules. The AOG1 protein shares no significant amino acid sequence similarity with other documented proteins and is located mainly in nuclei of the cells. Mutation in AOG1 caused degeneration of pollen at the uninucleate microspore stage and severe defect in embryo sacs, leading to a significant reduction in male and female fertility. Furthermore, the molecular analyses showed that the aog1 mutant significantly affected the expression of several genes, which are required for gametogenesis. Our results suggest that AOG1 plays important roles in gametogenesis at the stage prior to pollen mitosis I (PMI) in Arabidopsis, possibly through collaboration with other genes.

A highly basic protein isolated from bovine lens has been shown to be carbonic anhydrase III by immunological and peptide sequencing techniques. This is the first demonstration of the presence of this isoenzyme, which is primarily found in skeletal muscle, in the lens or other ocular tissues. The physiological function of this enzyme in the lens is unknown.

To analyze the clinical, imaging and pathological findings of congenital intrapulmonary lymphangioma and hemangioma in 5 infants and young children.Data of 3 cases with congenital intrapulmonary lymphangioma and 2 cases with haemangioma were analyzed.All the 5 cases had cough, difficulty in breathing, cyanosis of lips, and shortness of breath. Imaging study indicated cystic and space occupying changes of partial lung. In the two cases of hemangioma, the blood vessels passing through the hemangioma were observed on CT films. Histochemical studies showed that the cystic pockets from removed tissues were different in size and there was a line of flat endothelial tissue around these pockets. Immunochemical studies indicated D2-40 positive, factor VIII weak positive for lymphangioma cases; while in hemangioma cases, factor VIII was positive, D2-40 was negative or weakly positive, and both of cytokeratin was negative.It is very important to consider and identify congenital intrapulmonary lymphangioma or hemangioma when a patient has cystic pockets and space occupying change in their lung by imaging and pathological studies.

In this work, we propose a kind of supervised classification - support vector machine (SVM) to segment magnetic resonance image (MRI). As a classifier, SVM can employ structural risk minimization principle and perform better in classification task. Based on those excellent capabilities of SVM, we conduct many detailed experiments on some standard simulated data and real data. According to the experiments results, SVM is proven to be a good classifier in MRI segmentation.

Congenital nuclear cataracts transmitted by an autosomal dominant gene are present in a line of strain 13 N guinea-pigs. Studies on the lens proteins from these animals demonstrate changes in both the composition and structure of the crystallins relative to normal controls. The most prominent difference is in the ζ-crystallin, a taxon-specific crystallin which has been shown to be related to the alcohol dehydrogenases. In animals homozygous for the cataract phenotype the normal ζ-crystallin polypeptide is absent from the lens. Quantitation is difficult in the cataractous lenses from heterozygotes because of protein changes secondary to opacification: however in liver and kidney which have catalytic levels of the protein, the concentrations are approximately half that present in tissue from normal control animals. These findings suggest that in the cataractous animals a mutation has occurred in the gene for ζ-crystallin. In addition, a novel protein which is very similar to ζ-crystallin is synthesized only in the lenses of animals with cataract. This protein appears to be the product of the mutant gene for ζ-crystallin. These data support the hypothesis that this hereditary congenital cataract results from a specific mutation in the ζ-crystallin gene.

In this paper, we present a simplified particle system and fast translation algorithm to generate real-time animation of a music fountain (MF). This paper briefly describes our algorithms used to simplify the particle system and the process to build the physical model of the music fountain. Then the approach used to translate the controlling information into the fountain animation is introduced. Finally, the simulation results and conclusion are given.

Crystallins are the soluble structural proteins that constitute approximately 90% of the dry mass of the eye lens. The present study attempts to elucidate possible mechanisms whereby the H 2 O 2 present in the eye could contribute to the oxidative modification of lens crystallins. The data indicate that exposure of solutions of crystallins to H 2 O 2 and EDTA-chelated iron leads to covalent crosslinking of polypeptides, loss of intrinsic protein fluorescence, and the generation of a novel flurophor emitting in the 420 nm range. These changes closely mimic oxidative modifications that occur in lens proteins in vivo. Exposure of the proteins to H 2 O 2 in the absence of chelated iron failed to generate detectable levels of these modifications. These findings are contrasted with earlier studies of lenses in organ culture where H 2 O 2 alone produced marked damage while the further addition of chelated iron protected the lenses from oxidation.

In the paper, the authors establish an inequality involving exponential functions and sums, introduce a ratio of many gamma functions, discuss properties, including monotonicity, logarithmic convexity, (logarithmically) complete monotonicity, and the Bernstein function property, of the newly introduced ratio, and construct two inequalities of multinomial coefficients and multivariate beta functions., 10 pages