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1.
Front Neurorobot ; 18: 1446508, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165272

RESUMO

To reduce transportation time, a discrete zeroing neural network (DZNN) method is proposed to solve the shortest path planning problem with a single starting point and a single target point. The shortest path planning problem is reformulated as an optimization problem, and a discrete nonlinear function related to the energy function is established so that the lowest-energy state corresponds to the optimal path solution. Theoretical analyzes demonstrate that the discrete ZNN model (DZNNM) exhibits zero stability, effectiveness, and real-time performance in handling time-varying nonlinear optimization problems (TVNOPs). Simulations with various parameters confirm the efficiency and real-time performance of the developed DZNNM for TVNOPs, indicating its suitability and superiority for solving the shortest path planning problem in real time.

2.
Nat Prod Res ; 37(18): 3163-3169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36382781

RESUMO

Two new tigliane- and daphnane-type diterpenoids, given the trivial names daphnegens A-B (1-2) were isolated from the buds of Daphne genkwa. Their structures were assigned on the basis of extensive spectroscopic. The absolute configurations of both compounds were determined by comparison of their calculated and experimental CD curves. In addition, compounds 1-2 were tested for their cytotoxic activities against MCF-7 and HepG-2 human cancer cell lines, and compound 2 showed remarkable cytotoxic activity against HepG-2 cell line with the IC50 value of 11.5 µM.

3.
Anal Chem ; 94(38): 13000-13009, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36102213

RESUMO

In this work, the first version of "Glycomapping" software is developed for the analysis of the most common low-molecular-weight heparin (LMWH), enoxaparin. Using ultrahigh-performance liquid chromatography-mass spectrometry, size exclusion chromatography is applied, and a virtual database of glycans in enoxaparin is established for the initial searching. With "Glycomapping", a complex chromatogram can be fitted, significantly improving resolution and confirming an accurate distribution range for each size of glycan within enoxaparin. In addition, randomly matched MS data can be corrected, with the constraint of the corresponding chromatographic retention time range, to remove most false positive data. The analytical stability of "Glycomapping" software was confirmed. Enoxaparin, prepared by different manufacturers and from different animal sources, was analyzed using "Glycomapping." Compared to raw data, data processed with "Glycomapping" are more robust and accurate. Another two LMWHs, nadroparin and dalteparin could also be analyzed with this software. This work lays a solid foundation for the automated analysis of heterogeneous mixtures of natural glycans, such as LMWHs and other complex oligosaccharides and polysaccharides.


Assuntos
Enoxaparina , Heparina de Baixo Peso Molecular , Animais , Anticoagulantes , Cromatografia Líquida , Dalteparina , Enoxaparina/química , Heparina/química , Heparina de Baixo Peso Molecular/análise , Nadroparina/química , Software
4.
ACS Omega ; 7(11): 9582-9593, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350346

RESUMO

The great challenge facing additive manufacturing is that the available high-performance 3D printing materials can hardly keep up with the rapid development of new additive manufacturing technology. Then, the commercial resins available in the market have some problems, such as poor thermal stability, insufficient light-curing degree, and large shrinkage after curing, which need to be solved urgently. This study reports a photocurable polyimide ink for digital light processing (DLP) 3D printing to prepare controllable 3D structures with high thermal stability, low shrinkage, and excellent comprehensive properties. In this study, pyromellitic dianhydride and diaminodiphenyl ether, the Kapton polyimide with the highest performance synthesized so far, were selected as raw materials, and 2,2'-bis(3,4-dicarboxylic acid) hexafluoropropane dianhydride containing fluorine was introduced to modify the branched-chain structure. The polyimide was prepared by one-step imidization, and then the graft with photocurable double bonds and certain functions was grafted by reaction of glycidyl methacrylate with phenolic hydroxyl groups. In this work, the solubility of the synthesized oligomer polyimide in organic solvents was greatly increased by combining three methods, thereby allowing the formation of ink for photocuring 3D printing, and the ink can be stacked to form low-shrinkage polyimide with complex controllable shape. Polyimide printed by DLP can produce complex structures with good mechanical character and thermal stability and small shrinkage. Therefore, the polyimide prepared in this study is considered to be a resin of great commercial possibility. In addition, due to its properties, it has important development potential in some fields with high demand for thermal stability, such as high-temperature cooling valves, aerospace, and other fields.

5.
Ecology ; 96(1): 176-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26236902

RESUMO

Many community experiments have shown a positive relationship between plant biodiversity and community productivity, with biodiversity measured in multiple ways based on taxonomy, function, and phylogeny. Whether these different measures of biodiversity and their interactions explain variation in productivity in natural assemblages has rarely been tested. In a removal experiment using natural alpine assemblages in the Tibetan Plateau, we manipulated species richness and functional diversity to examine how different measures of biodiversity predict aboveground biomass production. We combined different biodiversity measures (functional, phylogenetic, richness, evenness) in generalized linear models to determine which combinations provided the most parsimonious explanations of variation in biomass production. Although multivariate functional diversity indices alone consistently explained more variation in productivity than other single measures, phylogenetic diversity and plant height represented the most parsimonious combination. In natural assemblages, single metrics alone cannot fully explain ecosystem function. Instead, a combination of phylogenetic diversity and traits with weak or no phylogenetic signal is required to explain the effects of biodiversity loss on ecosystem function.


Assuntos
Biodiversidade , Biomassa , Filogenia , Plantas , China
6.
Zhongguo Zhong Yao Za Zhi ; 39(19): 3865-9, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25612456

RESUMO

Asteraceae Echionopos (Echinops genus) is one of the world's plants commonly used in traditional Chinese medicine herbs. In this paper, a lot of literature on the basis of domestic and foreign, and modern research on the application of medicinal plants in different ethnic groups in our country Echionopos made a brief presentation and evaluation, and its in Chinese Han, Mongolian, Uygur, Kazak, Korean and other ethnic groups in the application of traditional medicine and related research conducted profiles. To further comprehensive and accurate use of the abundant plant resources and research, in order to find biologically active natural products, provide reference basis for the clinical application of new drugs developed and expanded drug source.


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/farmacologia , Animais , Tratamento Farmacológico , Medicamentos de Ervas Chinesas/química , Humanos , Medicina Tradicional Chinesa
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