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Moso bamboo (Phyllostachys edulis), once highly praised worldwide, has been found to be a problematic species due to its unconstrained expansion into adjacent woodlands and negative effects on the function services of forest ecosystems. To determine the major factors affecting bamboo expansion into neighbor woodlands, we investigated the expansion characteristics of moso bamboo and the properties of stand structure and soil for 58 bamboo–woodland interfaces (BWIs) across Jiangxi province in China. Then, we analyzed the relationships between the variables of bamboo expansion and the properties of interfaces through a redundancy analysis. The characteristics (the expansion distance and the number and size of new culms) of moso bamboo expansion into disturbed forests were more significant (p < 0.01) than those into non-disturbed forests. The bamboo expansion into deciduous broad-leaved forest was much faster (1.33 m/yr) than evergreen broad-leaved forest (0.82 m/yr) and needle-leaved forest (1.08 m/yr). The characteristics of stand structure had more direct explanatory power (58.8%) than soil properties (4.3%) and their interaction (10.0%) for the variations in bamboo expansion. The canopy closure of recipient forests was identified as the most significant factor negatively correlated to bamboo expansion. The number of parent culms and the ratio of deciduous to evergreen trees ranked in sequence, and both imposed positive effects on the expansion. Regarding soil properties, only the water content was identified for its explanatory power and negative influence on bamboo expansion. Our findings illustrated that the expansion of moso bamboo showed remarkable variations when facing different woodlands. Stand characteristics (canopy closure, canopy height, etc.) of good explanatory power were the major variables affecting the expansion of moso bamboo. In order to control the expansion of bamboo and protect woodlands, disturbances (extracting timber, girdling trunks) should be prevented in bamboo–woodland interfaces. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the chemical components of the flowers of Cymbidium Lunagrad Eternal Green for the first time. In the whole post-fertilization, a new alkaloid, named Lunagrad A (1), and a new aromatic glucoside, named Lunagrad B (2), were isolated from the MeOH extract of the flowers of Cymbidium Lunagrad Eternal Green, along with other six known aromatic compounds (3-8) and three flavone glucosides (9-11). These structures were determined on the basis of NMR experiments, as well as chemical evidence. [ABSTRACT FROM AUTHOR]

The acyclic organic alkynes and carbyne bonds exhibit linear shapes. Metallabenzynes and metallapentalynes are six- or five-membered metallacycles containing carbynes, whose carbine-carbon bond angles are less than 180°. Such distortion results in considerable ring strain, resulting in the unprecedented reactivity compared with acyclic carbynes. Meanwhile, the aromaticity of these metallacycles would stabilize the ring system. The fascinating combination of ring strain and aromaticity would lead to interesting reactivities. This mini review summarized recent findings on the reactivity of the metal–carbon triple bonds and the aromatic ring system. In the case of metallabenzynes, aromaticity would prevail over ring strain. The reactions are similar to those of organic aromatics, especially in electrophilic reactions. Meanwhile, fragmentation of metallacarbynes might be observed via migratory insertion if the aromaticity of metallacarbynes is strongly affected. In the case of metallapentalynes, the extremely small bond angle would result in high reactivity of the carbyne moiety, which would undergo typical reactions for organic alkynes, including interaction with coinage metal complexes, electrophilic reactions, nucleophilic reactions and cycloaddition reactions, whereas the strong aromaticity ensured the integrity of the bicyclic framework of metallapentalynes throughout all reported reaction conditions. [ABSTRACT FROM AUTHOR]

The total synthesis of a natural product alkaloid fusaric acid (FA), which exhibits herbicide, fungicide, insecticide and even diverse notable pharmacological activities, was accomplished in four steps using commercially available materials. The synthesis, based on a unified and flexible strategy using 6-bromonicotinaldehyde as a common intermediate, is concise, convergent, practical and can be carried out on a two-gram scale. This approach could be readily applicable to the synthesis of its analogues. In addition, FA had a wide range of inhibitory activities against 14 plant pathogenic fungi in this study, which demonstrated that as a leading compound, and it has great potential to be further developed as an agricultural fungicide. [ABSTRACT FROM AUTHOR]

Intelligent methods have long been researched in fault diagnosis. Traditionally, feature extraction and fault classification are separated, and this process is not completely intelligent. In addition, most traditional intelligent methods use an individual model, which cannot extract the discriminate features when the machines work in a complex condition. To overcome the shortcomings of traditional intelligent fault diagnosis methods, in this paper, an intelligent bearing fault diagnosis method based on ensemble sparse auto-encoders was proposed. Three different sparse auto-encoders were used as the main architecture. To improve the robustness and stability, a novel weight strategy based on distance metric and standard deviation metric was employed to assign the weights of three sparse auto-encodes. Softmax classifier is used to classify the fault types of integrated features. The effectiveness of the proposed method is validated with extensive experiments, and comparisons with the related methods and researches on the widely-used motor bearing dataset verify the superiority of the proposed method. The results show that the testing accuracy and the standard deviation are 99.71% and 0.05%. [ABSTRACT FROM AUTHOR]

The total synthesis of potent anti-obesity lansiumamide B was accomplished in four steps using commercially available materials. The synthetic strategy, featured with copper-catalyzed Buchwald coupling, is concise, convergent, practical and can be carried out on a one-gram scale. This approach could give either Z- or E-configured enamide moiety in natural products with absolute stereocontrol and was applied in the total synthesis of natural products. [ABSTRACT FROM AUTHOR]

A efficient 2-step protocol has been applied for the synthesis of Lansiumamide B ( N -methyl- N - cis -styryl-cinnamamide, 2 ) derivatives by various substitution on the amide nitrogen with alkyl, allyl, propargyl, benzyl or ester groups. The structures of nine new compounds were characterized by HRMS, ¹H NMR, and 13 C NMR spectra. These compounds were tested in vitro against 10 strains of phytopathogenic fungi and showed a wide antifungal spectrum. The relationship between different substituents on the amide nitrogen and antifungal activity of Lansiumamide B derivatives were compared and analyzed. The result indicates that the length and steric hindrance of N -substitution have a significant impact on biological activities. It is noteworthy that the methyl or ethyl substituent on the amide nitrogen is critical for the antifungal activities.

Five new taraxerene-type triterpenes, 2-nor-D-friedoolean-14-en-28-ol (1), 2-nor-d-friedoolean-14-en-3α,28-diol (2), 6α-hydroxy-2-nor-D-friedoolean-14-en-3,21-dione (3), 6α,11α,29-trihydroxy-D-friedoolean-14-en-3,16,21-trione (4), and 6α,23,29-trihydroxy-D-friedoolean-14-en-3,16,21-trione (5), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with five known compounds. Their structures were elucidated by means of various spectroscopic analyses. Five of the identified compounds showed moderate cytotoxicities against the cell proliferation of SGC-7901, MCF-7, and BEL-7404.

Three new ursane triterpenes, 3α,19α-dihydroxy-2-nor-urs-12-en-23,28-dioic acid-23-methyl ester (1), 19α,23-dihydroxy-3-oxo-2-nor-urs-12-en-28-oic acid (2), and 2,3-seco-3-methoxy-3,19α,23-trihydroxy-urs-12-en-2-al-28-oic acid (3), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with six known compounds. Their structures were elucidated by means of various spectroscopic analyses. The isolated triterpenes provide important evolutionary and chemotaxonomic knowledge about the monotypic genus Davidia. Five of the identified compounds showed moderate cytotoxicities against the cell proliferation of SGC-7901, MCF-7, and BEL-7404 with IC50 range from 7.26 to 47.41 μM.