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991.
Ha Yeun Song Kohji Mabuchi Takashi P. Satoh Jon A. Moore Yusuke Yamanoue Masaki Miya Mutsumi Nishida 《Gene》2014
Percomorpha, comprising about 60% of modern teleost fishes, has been described as the “(unresolved) bush at the top” of the tree, with its intrarelationships still being ambiguous owing to huge diversity (> 15,000 species). Recent molecular phylogenetic studies based on extensive taxon and character sampling, however, have revealed a number of unexpected clades of Percomorpha, and one of which is composed of Syngnathoidei (seahorses, pipefishes, and their relatives) plus several groups distributed across three different orders. To circumscribe the clade more definitely, we sampled several candidate taxa with reference to the previous studies and newly determined whole mitochondrial genome (mitogenome) sequences for 16 percomorph species across syngnathoids, dactylopterids, and their putatively closely-related fishes (Mullidae, Callionymoidei, Malacanthidae). Unambiguously aligned sequences (13,872 bp) from those 16 species plus 78 percomorphs and two outgroups (total 96 species) were subjected to partitioned Bayesian and maximum likelihood analyses. The resulting trees revealed a highly supported clade comprising seven families in Syngnathoidei (Gasterosteiformes), Dactylopteridae (Scorpaeniformes), Mullidae in Percoidei and two families in Callionymoidei (Perciformes). We herein proposed to call this clade “Syngnathiformes” following the latest nuclear DNA studies with some revisions on the included families. 相似文献
992.
A new species of genus Vitrea is described: Vitrea ulrichi
sp. n. is the eleventh species within the genus found in Bulgaria, and the largest representative of the Bulgarian Vitrea. Some critical notes on the taxonomy of the species V. bulgarica and V. sturanyi are presented. A key is provided for the determination of the species of Vitrea found in the country. 相似文献
993.
Dicranocentrus liuae
sp. n. is described from the northern subtropical region of China. The new species is most similar to D. wangi Ma & Chen, 2007, but differs from it in the relatively shorter Ant. V, the 1+1 central macrochaetae on Abd. III, the number of chaetae on tenaculum, and the absence of dental spines. The systematic position of Dicranocentrus is also discussed. Present evidence, particularly S-chaetotaxy, indicates that the genus is closer to Heteromurus than to the unscaled species of Orchesella and Orchesellides. 相似文献
994.
Eugenie Phillips-Rodríguez Jerry A. Powell Winnie Hallwachs Daniel H. Janzen 《ZooKeys》2014,(461):1-86
We discuss 45 Costa Rican species of Ethmia Hübner, 1819, including 23 previously described: Ethmia
delliella (Fernald), Ethmia
bittenella (Busck), Ethmia
festiva Busck, Ethmia
scythropa Walsingham, Ethmia
perpulchra Walsingham, Ethmia
terpnota Walsingham, Ethmia
elutella Busck, Ethmia
janzeni Powell, Ethmia
ungulatella Busck, Ethmia
exornata (Zeller), Ethmia
phylacis Walsingham, Ethmia
mnesicosma Meyrick, Ethmia
chemsaki Powell, Ethmia
baliostola Walsingham, Ethmia
duckworthi Powell, Ethmia
sandra Powell, Ethmia
nigritaenia Powell, Ethmia
catapeltica Meyrick, Ethmia
lichyi Powell, Ethmia
transversella Busck, Ethmia
similatella Busck, Ethmia
hammella Busck, Ethmia
linda Busck, and 22 new species: Ethmia
blaineorum, Ethmia
millerorum, Ethmia
dianemillerae, Ethmia
adrianforsythi, Ethmia
stephenrumseyi, Ethmia
berndkerni, Ethmia
dimauraorum, Ethmia
billalleni, Ethmia
ehakernae, Ethmia
helenmillerae, Ethmia
johnpringlei, Ethmia
laphamorum, Ethmia
petersterlingi, Ethmia
lesliesaulae, Ethmia
turnerorum, Ethmia
normgershenzi, Ethmia
nicholsonorum, Ethmia
hendersonorum, Ethmia
randyjonesi, Ethmia
randycurtisi, Ethmia
miriamschulmanae and Ethmia
tilneyorum. We illustrate all species and their male and female genitalia, along with distribution maps of Costa Rican localities. Immature stages are illustrated for 11 species, and food plants are listed when known. Gesneriaceae is added as a new food plant family record for Ethmia. CO1 nucleotide sequences (“DNA barcodes”) were obtained for 41 of the species. 相似文献
995.
996.
Rapid plant species loss at high rates and at low frequency of N addition in temperate steppe 总被引:2,自引:0,他引:2
Yunhai Zhang Xiaotao Lü Forest Isbell Carly Stevens Xu Han Nianpeng He Guangming Zhang Qiang Yu Jianhui Huang Xingguo Han 《Global Change Biology》2014,20(11):3520-3529
Humans are both intentionally (fertilization) and unintentionally (atmospheric nutrient deposition) adding nutrients worldwide. Increasing availability of biologically reactive nitrogen (N) is one of the major drivers of plant species loss. It remains unclear, however, whether plant diversity will be equally reduced by inputs of reactive N coming from either small and frequent N deposition events or large and infrequent N fertilization events. By independently manipulating the rate and frequency of reactive N inputs, our study teases apart these potentially contrasting effects. Plant species richness decreased more quickly at high rates and at low frequency of N addition, which suggests that previous fertilization studies have likely over‐estimated the effects of N deposition on plant species loss. N‐induced species loss resulted from both acidification and ammonium toxicity. Further study of small and frequent N additions will be necessary to project future rates of plant species loss under increasing aerial N deposition. 相似文献
997.
Xiankai Lu Qinggong Mao Frank S. Gilliam Yiqi Luo Jiangming Mo 《Global Change Biology》2014,20(12):3790-3801
Elevated anthropogenic nitrogen (N) deposition has greatly altered terrestrial ecosystem functioning, threatening ecosystem health via acidification and eutrophication in temperate and boreal forests across the northern hemisphere. However, response of forest soil acidification to N deposition has been less studied in humid tropics compared to other forest types. This study was designed to explore impacts of long‐term N deposition on soil acidification processes in tropical forests. We have established a long‐term N‐deposition experiment in an N‐rich lowland tropical forest of Southern China since 2002 with N addition as NH4NO3 of 0, 50, 100 and 150 kg N ha?1 yr?1. We measured soil acidification status and element leaching in soil drainage solution after 6‐year N addition. Results showed that our study site has been experiencing serious soil acidification and was quite acid‐sensitive showing high acidification (pH(H2O)<4.0), negative water‐extracted acid neutralizing capacity (ANC) and low base saturation (BS,< 8%) throughout soil profiles. Long‐term N addition significantly accelerated soil acidification, leading to depleted base cations and decreased BS, and further lowered ANC. However, N addition did not alter exchangeable Al3+, but increased cation exchange capacity (CEC). Nitrogen addition‐induced increase in SOC is suggested to contribute to both higher CEC and lower pH. We further found that increased N addition greatly decreased soil solution pH at 20 cm depth, but not at 40 cm. Furthermore, there was no evidence that Al3+ was leaching out from the deeper soils. These unique responses in tropical climate likely resulted from: exchangeable H+ dominating changes of soil cation pool, an exhausted base cation pool, N‐addition stimulating SOC production, and N saturation. Our results suggest that long‐term N addition can contribute measurably to soil acidification, and that shortage of Ca and Mg should receive more attention than soil exchangeable Al in tropical forests with elevated N deposition in the future. 相似文献
998.
《Process Biochemistry》2014,49(2):271-276
This work studied the effect of a sequential addition of substrate on tannase reaction for the increase of epigallocatechin (EGC) and gallic acid. The addition of 0.5–1% GTE increased the production of gallic acid during 2 h in a single tannase reaction, while the addition of more than 2% in GTE rather showed a decrease in gallic acid level with an increase of EGCG level compared with 1% GTE addition group, suggesting that GTE addition of 2% and over inhibits the reaction of tannase. Examination of sequential addition of 1% GTE on tannase reaction showed that second addition of 1% GTE at 2 h promoted tannase reaction by increasing production of gallic acid, but further addition (2 and 3 h) rather inhibited tannase reaction with lowered gallic acid and enhanced EGCG levels. This result showed that one additional treatment of 1% GTE during tannase reaction is effective in an increase of gallic acid production. Moreover, levels of degallated products including EGC, EC, and GC were increased by 7.3, 4.5, and 3.5-fold, respectively in sequential addition of GTE at 2 h. pH change derived from gallic acid production was not shown to related to tannase activity. Therefore, our study suggests that one sequential addition is a suitable process for desirable production of green tea extracts enriched in active components such as gallic acid and EGC. 相似文献
999.
Effects of N addition on ecological stoichiometric characteristics in six dominant plant species of alpine meadow on the Qinghai-Xizang Plateau,China 下载免费PDF全文
《植物生态学报》2014,38(3):231
以青藏高原高寒草甸为研究对象, 通过人工氮肥添加试验, 研究6个群落优势种在不同施氮(N)水平下叶片碳(C)、N、磷(P)元素含量的变化以及生态化学计量学特征。结果表明: 自然条件下, 6个物种叶片N、P质量浓度存在显著的差异, 表现为: 黄花棘豆(Oxytropis ochrocephala)最高, 为24.5和2.51 g·kg-1, 其叶片N含量低于而P含量高于我国其他草地的豆科植物; 其余5个物种叶片N、P质量浓度分别为11.5-18.1和1.49-1.72 g·kg-1, 嵩草(Kobresia myosuroides)叶片N含量最低, 垂穗披碱草(Elymus nutans)叶片P含量最低, 与我国其他区域的研究结果相比, 其叶片N和P含量均低于我国其他草地非豆科植物。随氮素添加量的增大, 6种群落优势种叶片的C和P含量保持不变; 其他5种植物叶片N含量显著增加, 黄花棘豆叶片N含量保持不变。未添加氮肥时, 6种植物叶片N:P为7.3-11.2, 说明该区植物生长更多地受N限制。随N添加量的增加, 除黄花棘豆外, 其他5种植物叶片N:P大于16, 表现为植物生长受P限制。综合研究表明, 青藏草原高寒草甸植物叶片N含量较低, 植物受N影响显著, 但不同物种对N的添加反应不同, 豆科植物黄花棘豆叶片对N添加不敏感, 其他5个物种叶片全N含量随着N添加量的升高而增加, 该研究结果可为高寒草甸科学施肥提供理论依据。 相似文献
1000.
《Bioorganic & medicinal chemistry》2014,22(3):1063-1069
A novel approach for the synthesis of unprecedented C3-mono-functionalized indolin-2-ones is reported, starting from 2-oxindole and chalcones. The reactions proceed regioselectively under mild conditions, without di- and tri-alkylated side products. The new compounds have been evaluated in vitro for their antiproliferative effects against the protozoan Leishmania infantum. Interestingly, they appear able to kill L. infantum promastigotes and amastigotes, without significant cytotoxic effects. 相似文献