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1.
Front Microbiol ; 13: 1054797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590418

RESUMO

Rice-fish coculture (RF) is a small ecosystem in which microorganisms are widely distributed in the fish, water environment, soil, and plants. In order to study the positive effects of microorganisms on common carp and rice in the RF ecosystem, a total of 18 strains with growth-promoting ability were screened from common carp (Cyprinus carpio) gut contents, among which three strains had the ability to produce both DDP-IV inhibitors and IAA. The strain with the strongest combined ability, FYN-22, was identified physiologically, biochemically, and by 16S rRNA, and it was initially identified as Bacillus licheniformis. As the number of metabolites secreted by the strain under natural conditions is not sufficient for production, the FYN-22 fermentation medium formulation was optimized by means of one-factor-at-a-time (OFAT) experiments and response surface methodology (RSM). The results showed that, under the conditions of a soluble starch concentration of 10.961 g/l, yeast concentration of 2.366 g/l, NH4Cl concentration of 1.881 g/l, and FeCl3 concentration of 0.850 g/l, the actual measured number of FYN-22 spores in the fermentation broth was 1.913 × 109 CFU/ml, which was 2.575-fold improvement over the pre-optimization value. The optimized fermentation solution was used for the immersion operation of rice seeds, and, after 14 days of incubation in hydroponic boxes, the FYN-22 strain was found to have a highly significant enhancement of 48.31% (p < 0.01) on the above-ground part of rice, and different degrees of effect on root length, fresh weight, and dry weight (16.73, 17.80, and 21.97%, respectively; p < 0.05). This study may provide new insights into the fermentation process of Bacillus licheniformis FYN-22 and its further utilization in RF systems.

2.
ISA Trans ; 118: 144-158, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33602523

RESUMO

Due to the outstanding characteristics of permanent magnet synchronous motor (PMSM), such as fast response speed, high torque and power density, it has been widely used in the automation industry. However, it remains a challenge to obtain high control performance caused by its dynamic complexity. In order to achieve favorable control performance, a novel state feedback control algorithm and parameter tuning method for permanent magnet synchronous motor is proposed in this paper. The development of the presented control method starts with the analyses of current state-space equation in rotor reference frame and then provides the design procedure of state feedback controller from the first-order to third-order system. An enhanced Proportional-Integral (PI) plus state feedback controller is designed, which includes the information of current, the error of current and the integral of the current error. The stability and convergence of the proposed control approach, as the extension of the conventional PI regulator, is mathematically justified in state feedback theory. The simulation and experimental results compared with the classical state feedback control method illustrate that the proposed PI plus state feedback control scheme can obtain better control performance in the presence of parameter changes and disturbance.

3.
Gene ; 753: 144798, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32445925

RESUMO

Gastric carcinoma (GC) ranks fifth in terms of cancer morbidity and third in cancer-related death worldwide and imposes enormous health and economic burdens. The molecular mechanisms underlying GC formation and progression remain unclear. Our aim was to identify the involvement of circular RNA circFOXO3 in GC, and to determine the underlying mechanisms. In this study, we revealed a stimulatory role of circular RNA circFOXO3 in tumor growth in vivo. CircFOXO3 enhanced GC cell proliferation and migration in vitro and promoted tumor growth of GC cells in vivo. Bioinformatic analysis revealed that circFOXO3 might regulate USP44 expression by specifically binding to microRNA (miR)-143-3p. Existence of circFOXO3-miR-143-3p-USP44 axis in GC cells was confirmed by RNA-binding protein immunoprecipitation, luciferase reporter assay, and an RNA pull-down experiments. All the data indicate that circFOXO3 promotes GC cell proliferation and migration by upregulating USP44 expression via targeting of miR-143-3p.


Assuntos
Ácidos Nucleicos Livres/metabolismo , Proteína Forkhead Box O3/genética , MicroRNAs/metabolismo , Neoplasias Gástricas/metabolismo , Ubiquitina Tiolesterase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Ácidos Nucleicos Livres/genética , Progressão da Doença , Transição Epitelial-Mesenquimal , Proteína Forkhead Box O3/metabolismo , Células HEK293 , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ativação Transcricional , Ubiquitina Tiolesterase/genética , Regulação para Cima
4.
ISA Trans ; 52(4): 510-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23477669

RESUMO

The traditional integer order proportional-integral-differential (IO-PID) controller is sensitive to the parameter variation or/and external load disturbance of permanent magnet synchronous motor (PMSM). And the fractional order proportional-integral-differential (FO-PID) control scheme based on robustness tuning method is proposed to enhance the robustness. But the robustness focuses on the open-loop gain variation of controlled plant. In this paper, an enhanced robust fractional order proportional-plus-integral (ERFOPI) controller based on neural network is proposed. The control law of the ERFOPI controller is acted on a fractional order implement function (FOIF) of tracking error but not tracking error directly, which, according to theory analysis, can enhance the robust performance of system. Tuning rules and approaches, based on phase margin, crossover frequency specification and robustness rejecting gain variation, are introduced to obtain the parameters of ERFOPI controller. And the neural network algorithm is used to adjust the parameter of FOIF. Simulation and experimental results show that the method proposed in this paper not only achieve favorable tracking performance, but also is robust with regard to external load disturbance and parameter variation.


Assuntos
Algoritmos , Retroalimentação , Magnetismo/instrumentação , Modelos Teóricos , Redes Neurais de Computação , Análise Numérica Assistida por Computador , Simulação por Computador
5.
ISA Trans ; 51(5): 649-56, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22709529

RESUMO

A fractional order sliding mode control (FROSMC) scheme based on parameters auto-tuning for the velocity control of permanent magnet synchronous motor (PMSM) is proposed in this paper. The control law of the proposed F(R)OSMC scheme is designed according to Lyapunov stability theorem. Based on the property of transferring energy with adjustable type in F(R)OSMC, this paper analyzes the chattering phenomenon in classic sliding mode control (SMC) is attenuated with F(R)OSMC system. A fuzzy logic inference scheme (FLIS) is utilized to obtain the gain of switching control. Simulations and experiments demonstrate that the proposed FROSMC not only achieve better control performance with smaller chatting than that with integer order sliding mode control, but also is robust to external load disturbance and parameter variations.


Assuntos
Transferência de Energia , Retroalimentação , Magnetismo , Modelos Teóricos , Simulação por Computador , Movimento (Física)
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