Palmiers coryphoïdés de l’Oligocène de Chine et leurs implications biogéographiques

Des feuilles de palmiers fossiles en provenance de dépôts oligocènes du Comté de Ningming, Guangxi, Chine ont été enregistrées pour la première fois. La forme de la feuille de palmier, de même qu’une nervure bien définie sont des arguments pour placer ces fossiles au sein des Coryphoideae. Trois nouvelles espèces sont décrites : Chuniophoenix slenderifolia sp. nov., Livistona roundifolia sp. nov., et Trachycarpus formosa. Les fossiles de palmiers appartiennent à trois taxons et indiquent que les palmiers du Sud de la Chine ont commencé à se diversifier dès l’Oligocène et qu’une flore diversifiée de palmiers était déjà présente à cette époque dans le Guangxi. Cet enregistrement apporte de nouvelles informations sur l’histoire biogéographique des palmiers de Chine uau cours des temps géologiques.Fossil palm leaves from the Oligocene deposits in Ningming County, Guangxi, China, have been reported for the first time. The palmate leaf shape along with a definite costa support the placement of the fossils in the Coryphoideae. Three new species are described: Chuniophoenix slenderifolia sp. nov., Livistona roundifolia sp. nov. and Trachycarpus formosa sp. nov. The palm fossils belong to three taxa and indicate that palms in southern China began to diversify no later than the Oligocene and that a diversified palm flora was already present at that time in Guangxi. This report provides new information about the biogeographical history of Chinese palms over geological time.</p

Attribute Reduction Algorithm Based on Structure Discernibility Matrix in Composite Information Systems

Attribute reduction, as an important preprocessing step for knowledge acquiring in data mining, is one of the key issues in rough set theory. It can only deal with attributes of a specific type in the information system by using a specific binary relation. However, there may be attributes of multiple different types in information systems in real-life applications. A composite relation is proposed to process attributes of multiple different types simultaneously in composite information systems. In order to solve the time-consuming problem of traditional heuristic attribute reduction algorithms, a novel attribute reduction algorithm based on structure discernibility matrix was proposed in this paper. The proposed algorithms can choose the same attribute reduction as its previous version, but it can be used to accelerate a heuristic process of attribute reduction by avoiding the process of intersection and adopting the forward greedy attribute reduction approach. The theoretical analysis and experimental results with UCI data sets show that the proposed algorithm can accelerate the heuristic process of attribute reduction

Attribute Reduction Algorithm Based on Structure Discernibility Matrix in Composite Information Systems

Attribute reduction, as an important preprocessing step for knowledge acquiring in data mining, is one of the key issues in rough set theory. It can only deal with attributes of a specific type in the information system by using a specific binary relation. However, there may be attributes of multiple different types in information systems in real-life applications. A composite relation is proposed to process attributes of multiple different types simultaneously in composite information systems. In order to solve the time-consuming problem of traditional heuristic attribute reduction algorithms, a novel attribute reduction algorithm based on structure discernibility matrix was proposed in this paper. The proposed algorithms can choose the same attribute reduction as its previous version, but it can be used to accelerate a heuristic process of attribute reduction by avoiding the process of intersection and adopting the forward greedy attribute reduction approach. The theoretical analysis and experimental results with UCI data sets show that the proposed algorithm can accelerate the heuristic process of attribute reduction

Pharmacokinetic-pharmacodynamic profiling of four antimicrobials against Gram-negative bacteria collected from Shenyang, China

Abstract Background To examine common antimicrobial regimens used in eradicating certain nosocomial Gram-negative pathogens and determine which ones are likely to be the most suitable as empirical choices in Shenyang, China. Methods A 5000-subject Monte Carlo simulation was conducted to determine the cumulative fraction of response (CFR) for meropenem, imipenem, cefepime, piperacillin/tazobactam and levofloxacin against Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Acinetobacter baumannii and Pseudomonas aeruginosa collected in 2006 and 2007 from Shenyang. Results Meropenem and imipenem had the highest CFRs against the Enterobacteriaceae (97%-100%), followed by cefepime. No antibiotic simulated regimen achieved optimal CFR against P. aeruginosa and A. baumannii. Piperacillin/tazobactam dosed at 4.5 g q8h achieved the lowest CFR against all bacteria. Conclusions This study suggests that the carbapenems provide the greatest likelihood of clinical success for the Enterobacteriaceae, and combination therapy might be needed when choosing empirical therapy, especially when A. baumannii or P. aeruginosa are suspected.</p

First occurrence of Platycladus from the upper Miocene of Southwest China and its phytogeographic implications.

Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera

Single SNP- and pathway-based genome-wide association studies for beak deformity in chickens using high-density 600K SNP arrays

Abstract Background Beak deformity, typically expressed as the crossing of upper and lower mandibles, is found in several indigenous chicken breeds, including the Beijing-You chickens studied here. Beak deformity severely impairs the birds’ growth and welfare. Although previous studies shed some light on the genetic regulation of this complex trait, the genetic basis of this malformation remains incompletely understood. Results In this study, single SNP- and pathway-based genome-wide association studies (GWASs) were performed using ROADTRIPS and SNP ratio test (SRT), respectively. A total of 48 birds with deformed beaks (case) and 48 normal birds (control) were genotyped using Affymetrix 600 K HD genotyping arrays. As a result, 95 individuals and 429,539 SNPs were obtained after quality control. The P-value was corrected by a Bonferroni adjustment based on linkage disequilibrium pruning. The single SNP-based association study identified one associated SNP with 5% genome-wide significance and seven suggestively associated SNPs. Four high-confidence genes, LOC421892, TDRD3, RET, and STMN1, were identified as the most promising candidate genes underlying this complex trait in view of their positions, functions, and overlaps with previous studies. The pathway-based association study highlighted the association of six pathways with beak deformity, including the calcium signaling pathway. Conclusions Potentially useful candidate genes and pathways for beak deformity were identified, which should be the subject of further functional characterization

Opposing effects of nitrogen and water addition on soil bacterial and fungal communities in the Inner Mongolia steppe: a field experiment.

Grasslands are important ecosystems and make up 40% of the terrestrial ecosystems worldwide. The Inner Mongolia steppe is the main grassland region of China, and nitrogen (N) and water availability are two important factors that limit the productivity of these grasslands. We tested how N and water addition influence the composition of the microbial community in the soil using PLFA, and soil physical and chemical properties in two semiarid grassland sites in Inner Mongolia during two consecutive years. In both sites, a split-plot design was employed with two water treatments (natural precipitation, stimulated wet year precipitation) and three N treatments (0 kg N ha⁻¹, 25 kg N ha⁻¹, 50 kg N ha⁻¹). Water addition greatly increased soil fungi and decreased bacteria while N had opposite effects. Water addition resulted in a significant increase in soil pH and electric conductivity. N addition did not lead to consistent changes in soil characteristics. Multivariate analysis showed that PLFA composition varied between all treatments but was mainly influenced by water addition. This study provides insight into how climatic changes such as alternations in rainfall and N deposition shape the soil microbial communities in Inner Mongolia steppes

A-G. Cuticles of <i>Platycladus yunnanensis</i> sp. nov. under light microscope.

<p>A. Abaxial cuticle of facial leaf. LZLH–3021. B. Cuticles of the facial leaves (black arrows) and lateral leaf (green arrow) in the bifurcation of branchlets. Sampling from the area of green box in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115141#pone-0115141-g003" target="_blank">Fig. 3I</a>. C. Abaxial cuticle of lateral leaf. LULH–4487. D. Adaxial cuticle of lateral leaf. LULH–4487. E. Stomatal zone of the abaxial cuticle of facial leaf. LZLH–3021. F. Stomatal zone of the adaxial cuticle of facial leaf. LZLH–3021. G. Stomatal zone of the abaxial cuticle of lateral leaf. LZLH–3021. H-K. Cuticles of extant <i>Platycladus orientalis</i> under light microscope. H. Adaxial cuticle of facial leaf. I. Adaxial cuticle of lateral leaf. J. Stomatal zone in the abaxial cuticle of facial leaf. K. Stomatal zone in the abaxial cuticle of lateral leaf. A-D, H, I. Scale bar  = 1 mm. E-G, J, K. Scale bar  = 100 µm.</p

Comparison of leaf morphology with the relevant species of Cupressoideae <i>s.l.</i>[1], [2].

<p>Comparison of leaf morphology with the relevant species of Cupressoideae <i>s.l.</i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115141#pone.0115141-Fu1" target="_blank">[1]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115141#pone.0115141-Farjon1" target="_blank">[2]</a>.</p

The stratigraphic section through the upper Miocene Nanlin Formation in Lianghe County, Yunnan Province, Southwest China [11]–[13].

<p>The stratigraphic section through the upper Miocene Nanlin Formation in Lianghe County, Yunnan Province, Southwest China <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115141#pone.0115141-Ge1" target="_blank">[11]</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115141#pone.0115141-Zhuo1" target="_blank">[13]</a>.</p