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1.
Nat Commun ; 15(1): 5139, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886388

ABSTRACT

Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.


Subject(s)
Biodiversity , Magnoliopsida , Phylogeny , China , Magnoliopsida/growth & development , Altitude , Geological Phenomena , Ecosystem
2.
J Org Chem ; 87(17): 11491-11502, 2022 09 02.
Article in English | MEDLINE | ID: mdl-35951357

ABSTRACT

A convenient synthesis of methylene-bridged pyrrolo[2,1-a]isoquinolines has been developed. Treatment of pyrroloisoquinolines with acetyl chloride and dimethylsulfoxide (DMSO) at ambient temperature afforded bispyrroloisoquinolylmethanes in 17-85% yields. This reaction system can also be expanded to the synthesis of bispyrrolylmethanes (34-94% yields). Easy chemical transformation of methylene-bridged pyrroloisoquinoline provided an unsymmetric acid and amide possessing a privileged framework.


Subject(s)
Isoquinolines , Pyrroles , Acetates , Chlorides , Dimethyl Sulfoxide
3.
Math Biosci Eng ; 17(5): 5672-5685, 2020 08 26.
Article in English | MEDLINE | ID: mdl-33120572

ABSTRACT

To address the problem of steel strip surface defect detection, a feature fusion-based preprocessing strategy is proposed based on machine vision technology. This strategy can increase the feature dimension of the image, highlight the pixel features of the image, and improve the recognition accuracy of the convolutional neural network. This method is based on commonly used image feature extraction operators (e.g., Sobel, Laplace, Prewitt, Robert, and local binary pattern) to process the defect image data, extract the edges and texture features of the defect image, and fuse the grayscale image processed by the feature operator with the original grayscale image by using three channels. To consider also computational efficiency and reduce the number of calculation parameters, the three channels are converted into a single channel according to a certain weight ratio. With this strategy, the steel plate surface defect database of NEU is processed, and fusion schemes with different operator combinations and different weight ratios for conversion to the single channel are explored. The test results show that, under the same network framework and with the same computational cost, the fusion scheme of Sobel:image:Laplace and the single-channel conversion weight ratio of 0.2:0.6:0.2 can improve the recognition rate of a previously unprocessed image by 3% and can achieve a final accuracy rate of 99.77%, thereby demonstrating the effectiveness of the proposed strategy.

4.
Neural Regen Res ; 11(10): 1653-1659, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27904498

ABSTRACT

Schwann cells play an important role in the peripheral nervous system, especially in nerve repair following injury, so artificial nerve regeneration requires an effective technique for obtaining purified Schwann cells. In vivo and in vitro pre-degeneration of peripheral nerves have been shown to obtain high-purity Schwann cells. We believed that in vitro pre-degeneration was simple and controllable, and available for the clinic. Thus, we co-cultured the crushed sciatic nerves with bone marrow-derived cells in vitro. Results demonstrated that, 3 hours after injury, a large number of mononuclear cells moved to the crushed nerves and a large number of bone marrow-derived cells infiltrated the nerve segments. These changes promoted the degradation of the nerve segments, and the dedifferentiation and proliferation of Schwann cells. Neural cell adhesion molecule and glial fibrillary acidic protein expression were detected in the crushed nerves. Schwann cell yield was 9.08 ± 2.01 × 104/mg. The purity of primary cultured Schwann cells was 88.4 ± 5.79%. These indicate a successful new method for obtaining Schwann cells of high purity and yield from adult crushed sciatic nerve using bone marrow-derived cells.

5.
Zhonghua Nan Ke Xue ; 21(1): 61-4, 2015 Jan.
Article in Chinese | MEDLINE | ID: mdl-25707143

ABSTRACT

OBJECTIVE: To observe the effectiveness of Bushen Huoxue Decoction in improving the erectile function of male patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI) with stent implantation. METHODS: Eighty male CHD patients after PCI with stent implantation were equally assigned to receive conventional Western medicine (control group) and combination of Western medicine with Bushen Huoxue Decoction (treatment group), both for 3 months. Then we compared the pre- and post-medication IIEF-5 scores between the two groups of patients. RESULTS: Compared with pre-medication, the total IIEF-5 score was significantly increased after 3 months both in the treatment group (8.19 ± 2.87 vs 17.83 ± 4.92, P <0.05) and in the control (7.98 ± 2.96 vs 12.18 ± 3.69, P <0.05), even higher in the former than in the latter group (P <0.05), and so were the scores on the 5 specific items (all P <0.05). The total effectiveness rate was 72.5% in the treatment group, significantly higher than 47.5% in the control (P <0.05). No obvious adverse reactions and events were observed during the treatment in either of the groups. CONCLUSION: Bushen Huoxue Decoction can obviously improve the erectile function and the quality of the sexual life of CHD patients after PCI with stent implantation.


Subject(s)
Coronary Disease/surgery , Drugs, Chinese Herbal/therapeutic use , Penile Erection/drug effects , Percutaneous Coronary Intervention , Phytotherapy , Humans , Male , Penile Erection/physiology , Stents
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