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41.
Temperature in agricultural production has a direct impact on the growth of crops. The emergence of greenhouses has improved the impact of the original unpredictable changes in temperature, but the temperature modeling of greenhouses is still the main direction at present. Neural network modeling relies on sufficient actual data
to model greenhouses, but there is a widening gap in the application of different neural networks. This paper
proposes a greenhouse temperature prediction model based on wavelet neural network with genetic algorithm
(GA-WNN). With the simple network structure and the nonlinear adaptability of the wavelet basis function,
wavelet neural network (WNN) improved model training speed and accuracy of prediction results compared with
back propagation neural networks (BPNN), which was conducive to the prediction and control of short-term
greenhouse temperature fluctuations. At the same time, the genetic algorithm (GA) was introduced to globally
optimize the initial weights of the original model, which improved the insensitivity of the model to the initial
weights and thresholds, and improved the training speed and stability of the model. Finally, simulation results
for the greenhouse showed that the model training speed, prediction results accuracy and model stability of
the GA-WNN in the greenhouse were improved in comparison to results obtained by the WNN and BPNN
in the greenhouse. 相似文献
42.
Cui Junmei Hu Yang Huang Yan Guo Jinya Xie Xiulan Zhang Huaiyu Cai Yi 《Plant Molecular Biology Reporter》2022,40(1):68-80
Plant Molecular Biology Reporter - Plants are subjected to a variety of environmental stressors, including salinity, drought and pathogens, and have consequently developed a sophisticated sensing... 相似文献
43.
She Yang Gao Xiang Jing Xin Wang Jing Dong Yibei Cui Jinzi Xue Huidan Li Zhengke Zhu Derui 《Journal of applied phycology》2022,34(3):1281-1291
Journal of Applied Phycology - A new strain of Eustigmatophyceae, Vischeria sp. WL1, which accumulates oil droplets in the cells, was isolated from a large biological soil crust in the arid steppes... 相似文献
44.
Cytotechnology - Polycystic ovarian syndrome (PCOS) is a frequent metabolic disorder in premenopausal woman, featured with increased androgen, reduced ovulation and insulin resistance. An... 相似文献
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Fuqiang Zhang Feng Hao Dong An Linlin Zeng Yi Wang Xuemin Xu Mei-Zhen Cui 《The Journal of biological chemistry》2015,290(13):8232-8242
Platelet-derived growth factor (PDGF), a potent chemoattractant, induces cell migration via the MAPK and PI3K/Akt pathways. However, the downstream mediators are still elusive. In particular, the role of extracellular mediators is largely unknown. In this study, we identified the matricellular protein Cyr61, which is de novo synthesized in response to PDGF stimulation, as the key downstream mediator of the ERK and JNK pathways, independent of the p38 MAPK and AKT pathways, and, thereby, it mediates PDGF-induced smooth muscle cell migration but not proliferation. Our results revealed that, when Cyr61 was newly synthesized by PDGF, it was promptly translocated to the extracellular matrix and physically interacted with the plasma membrane integrins α6β1 and αvβ3. We further demonstrate that Cyr61 and integrins are integral components of the PDGF signaling pathway via an “outside-in” signaling route to activate intracellular focal adhesion kinase (FAK), leading to cell migration. Therefore, this study provides the first evidence that the PDGF-induced endogenous extracellular matrix component Cyr61 is a key mediator in modulating cell migration by connecting intracellular PDGF-ERK and JNK signals with integrin/FAK signaling. Therefore, extracellular Cyr61 convergence with growth factor signaling and integrin/FAK signaling is a new concept of growth factor-induced cell migration. The discovered signaling pathway may represent an important therapeutic target in growth factor-mediated cell migration/invasion-related vascular diseases and tumorigenesis. 相似文献
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