Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 930
Filtrar
1.
Phytochemistry ; : 114090, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599509

RESUMO

In this study, ten phenylpropionyl phenylethylamines, including five previously undescribed ones (1a/b, 2a/b, and 3), five known analogues (4 - 8), and two established phenylpropanoids precursors (9, 10) were isolated from the aerial parts of Chloranthus henryi Hemsl. Their structures, including absolute configurations, were determined by high-resolution mass spectrometry, enantio-separation, electronic circular dichroism calculation, and single crystal diffraction. Compounds 1a and 1b were the first examples of natural hetero-[2 + 2] cycloaddition products between phenylpropionyl phenylethylamine and phenylpropene. The plausible hetero-[2 + 2] biosynthesis pathway was confirmed by a photocatalytic biomimetic synthesis in eight steps, which also led to the production of three other potential natural homo-[2 + 2] adducts (1'a/b, 2', and 3'). Bioactivity screening indicated that these adducts bear medium inhibitory activity on nitric oxide generation, with IC50 values of 6 - 35 µM in RAW 264.7 macrophages.

2.
Chem Sci ; 15(12): 4364-4373, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516094

RESUMO

π-π coupling as a common interaction plays a key role in emissions, transport and mechanical properties of organic materials. However, the precise control of π-π coupling is still challenging owing to the possible interference from other intermolecular interactions in the aggregated state, usually resulting in uncontrollable emission properties. Herein, with the rational construction of intramolecular dimer models and crystal engineering, π-π coupling can be subtly modulated by conformation variation with balanced π-π and π-solvent interactions and visualized by green-to-blue emission switching. Moreover, it can rapidly respond to temperature, pressure and mechanical force, affording a facile way to modulate π-π coupling in situ. This work contributes to a deeper understanding of the internal mechanism of molecular motions in aggregated states.

3.
J Agric Food Chem ; 72(12): 6625-6637, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38494953

RESUMO

The LC-MS-based method has emerged as the preferred approach for quantifying food allergens. However, the preparation of a traditional calibration curve (MSCC) is labor-intensive and error-prone. Here, a sensitive and robust LC-MS/MS method for quantifying 10 major food allergens was developed and validated, where the one-sample multipoint external calibration curve (OSCC) was employed instead of MSCC. By employing the multiple isotopologue reaction monitoring (MIRM) technique with only one spiked level in the blank, OSCC can be effectively established. Results demonstrate that the proposed method exhibits excellent performance in selectivity, sensitivity, accuracy, and precision, comparable to that of the traditional MSCC. Additionally, this strategy allows for isotope sample dilution by monitoring the less abundant MIRM channel. Moreover, the developed method was successfully applied to investigate the contamination of 10 food allergens in commercial food products. With its high throughput and robustness, the MIRM-OSCC-LC-MS/MS methodology has many potential applications, especially in the MS-based protein quantification analysis.


Assuntos
Hipersensibilidade Alimentar , 60705 , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Calibragem , Alérgenos/análise
4.
J Agric Food Chem ; 72(12): 6155-6166, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38498691

RESUMO

The migration and transformation of allelochemicals are important topics in the exploration of allelopathy. Current research on the migration of allelochemicals mostly uses soil column and thin layer methods and verifies it by sowing plant seeds. However, traditional methods inevitably ignore the flux caused by the movement of allelochemicals carried by water. In fact, the flux determines the amount of allelochemicals that directly affect plants. In this work, a method of microdialysis combined with a soil column and UPLC-MS/MS to detect the flux of allelochemicals was developed for the first time and successfully applied to the detection of five taxane allelochemicals in soil. Meanwhile, by adding taxane allelochemicals to the soil and detecting their transformation products using UPLC-MS/MS, the half-life of taxane in the soil was determined, and the transformation pathway of taxane allelochemicals in the soil was further speculated.


Assuntos
Feromônios , Solo , Feromônios/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Plantas/metabolismo
5.
Discov Oncol ; 15(1): 66, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446289

RESUMO

Serum amyloid A1 (SAA1), an inflammation-related molecule, is associated with the malignant progression of many tumors. This study aimed to investigate the role of SAA1 in the progression of esophageal squamous cell carcinoma (ESCC) and its molecular mechanisms. The expression of SAA1 in ESCC tissues and cell lines was analyzed using bioinformatics analysis, western blotting, and reverse transcription-quantitative PCR (RT‒qPCR). SAA1-overexpressing or SAA1-knockdown ESCC cells were used to assess the effects of SAA1 on the proliferation, migration, apoptosis of cancer cells and the growth of xenograft tumors in nude mice. Western blotting, immunofluorescence and RT‒qPCR were used to investigate the relationship between SAA1 and ß-catenin and SAA1 and sphingosine 1-phosphate (S1P)/sphingosine 1-phosphate receptor 1 (S1PR1). SAA1 was highly expressed in ESCC tissues and cell lines. Overexpression of SAA1 significantly promoted the proliferation, migration and the growth of tumors in nude mice. Knockdown of SAA1 had the opposite effects and promoted the apoptosis of ESCC cells. Moreover, SAA1 overexpression promoted the phosphorylation of ß-catenin at Ser675 and increased the expression levels of the ß-catenin target genes MYC and MMP9. Knockdown of SAA1 had the opposite effects. S1P/S1PR1 upregulated SAA1 expression and ß-catenin phosphorylation at Ser675 in ESCC cells. In conclusion, SAA1 promotes the progression of ESCC by increasing ß-catenin phosphorylation at Ser675, and the S1P/S1PR1 pathway plays an important role in its upstream regulation.

6.
Front Cardiovasc Med ; 11: 1342529, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455718

RESUMO

Acute extensive portal venous system thrombosis (PVST) can cause lethal complications. Herein, we have for the first time reported the use of anticoagulation combined with systemic thrombolysis by tenecteplase in a male patient with a diagnosis of acute extensive PVST but without liver cirrhosis. After thrombolytic therapy, abdominal pain obviously alleviated. However, urinary bleeding developed, which was reversible by stopping thrombolytic drugs. Finally, this case developed cavernous transformation of the portal vein without portal venous recanalization. In future, the efficacy and safety of tenecteplase should be explored in acute extensive PVST cases.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124166, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493512

RESUMO

Rapid, effective and non-destructive detection of the defective maize kernels is crucial for their high-quality storage in granary. Hyperspectral imaging (HSI) coupled with convolutional neural network (CNN) based on spectral and spatial attention (Spl-Spal-At) module was proposed for identifying the different types of maize kernels. The HSI data within 380-1000 nm of six classes of sprouted, heat-damaged, insect-damaged, moldy, broken and healthy kernels was collected. The CNN-Spl-At, CNN-Spal-At and CNN-Spl-Spal-At models were established based on the spectra, images and their fusion features as inputs for the recognition of different kernels. Further compared the performances of proposed models and conventional models were built by support vector machine (SVM) and extreme learning machine (ELM). The results indicated that the recognition ability of CNN with attention series models was significantly better than that of SVM and ELM models and fused features were more conducive to expressing the appearance of different kernels than single features. And the CNN-Spl-Spal-At model had an optimal recognition result with high average classification accuracy of 98.04 % and 94.56 % for the training and testing sets, respectively. The recognition results were visually presented on the surface image of kernels with different colors. The CNN-Spl-Spal-At model was built in this study could effectively detect defective maize kernels, and it also had great potential to provide the analysis approaches for the development of non-destructive testing equipment based on HSI technique for maize quality.


Assuntos
Imageamento Hiperespectral , Zea mays , Temperatura Alta , Redes Neurais de Computação , Máquina de Vetores de Suporte
8.
Front Immunol ; 15: 1336586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504987

RESUMO

Introduction: Sepsis represents a critical medical condition that arises due to an imbalanced host reaction to infection. Central to its pathophysiology are cytokines. However, observational investigations that explore the interrelationships between circulating cytokines and susceptibility to sepsis frequently encounter challenges pertaining to confounding variables and reverse causality. Methods: To elucidate the potential causal impact of cytokines on the risk of sepsis, we conducted two-sample Mendelian randomization (MR) analyses. Genetic instruments tied to circulating cytokine concentrations were sourced from genome-wide association studies encompassing 8,293 Finnish participants. We then evaluated their links with sepsis and related outcomes using summary-level data acquired from the UK Biobank, a vast multicenter cohort study involving over 500,000 European participants. Specifically, our data spanned 11,643 sepsis cases and 474,841 controls, with subsets including specific age groups, 28-day mortality, and ICU-related outcomes. Results and Discussion: MR insights intimated that reduced genetically-predicted interleukin-10 (IL-10) levels causally correlated with a heightened sepsis risk (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.52-0.90, P=0.006). An inverse relationship emerged between monocyte chemoattractant protein-1 (MCP-1) and sepsis-induced mortality. Conversely, elevated macrophage inflammatory protein 1 beta (MIP1B) concentrations were positively linked with both sepsis incidence and associated mortality. These revelations underscore the causal impact of certain circulating cytokines on sepsis susceptibility and its prognosis, hinting at the therapeutic potential of modulating these cytokine levels. Additional research is essential to corroborate these connections.


Assuntos
Citocinas , Sepse , Humanos , Estudos de Coortes , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Sepse/genética
9.
Nat Plants ; 10(4): 539-550, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503962

RESUMO

The plant DNA damage response (DDR) pathway safeguards genomic integrity by rapid recognition and repair of DNA lesions that, if unrepaired, may cause genome instability. Most frequently, DNA repair goes hand in hand with a transient cell cycle arrest, which allows cells to repair the DNA lesions before engaging in a mitotic event, but consequently also affects plant growth and yield. Through the identification of DDR proteins and cell cycle regulators that react to DNA double-strand breaks or replication defects, it has become clear that these proteins and regulators form highly interconnected networks. These networks operate at both the transcriptional and post-transcriptional levels and include liquid-liquid phase separation and epigenetic mechanisms. Strikingly, whereas the upstream DDR sensors and signalling components are well conserved across eukaryotes, some of the more downstream effectors are diverged in plants, probably to suit unique lifestyle features. Additionally, DDR components display functional diversity across ancient plant species, dicots and monocots. The observed resistance of DDR mutants towards aluminium toxicity, phosphate limitation and seed ageing indicates that gaining knowledge about the plant DDR may offer solutions to combat the effects of climate change and the associated risk for food security.

10.
Fish Shellfish Immunol ; 148: 109476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447780

RESUMO

Trachinotus ovatus is an economically important fish and has been recommended as a high-quality aquaculture fish breed for the high-quality development of sea ranches in the South China Sea. However, T. ovatus shows intolerance to low temperature, greatly limiting the extension of farming scale, reducing production efficiency in winter, and increasing farming risks. In this study, liver transcriptome analysis was investigated in T. ovatus under acute low temperature conditions (20 and 15 °C) using RNA sequencing (RNA-Seq) technology. Inter-groups differential expression analysis and trend analysis screened 1219 DEGs and four significant profiles (profiles 0, 3, 4, and 7), respectively. GO enrichment analysis showed that these DEGs were mainly related to metabolic process and cell growth and death process. KEGG enrichment analysis found that DEGs were mainly associated with lipid metabolism, carbohydrate metabolism, and cell growth and death, such as gluconeogenesis, glycolysis, fatty acid oxidation, cholesterol biosynthesis, p53 signaling pathway, cell cycle arrest, and apoptotic cell death. Moreover, protein-protein interaction networks identified two hub genes (FOS and JUNB) and some important genes related to metabolic process and cell growth and death process, that corresponding to enrichment analysis. Overall, gluconeogenesis, lipid mobilization, and fatty acid oxidation in metabolic process and cell cycle arrest and apoptotic cell death in cell growth and death process were enhanced, while glycolysis, liver glycogen synthesis and cholesterol biosynthesis in metabolic process were inhibited. The enhancement or attenuatment of metabolic process and cell growth and death process is conducive to maintain energy balance, normal fluidity of cell membrane, normal physiological functions of liver cell, enhancing the tolerance of T. ovatus to cold stress. These results suggested that metabolic process and cell growth and death process play important roles in response to acute cold stress in the liver of T. ovatus. Gene expreesion level analysis showed that acute cold stress at 15 °C was identified as a critical temperature point for T. ovatus in term of cellular metabolism alteration and apoptosis inducement, and rewarming intervention should be timely implemented above 15 °C. Our study can provide theoretical support for breeding cold-tolerant cultivars of T. ovatus, which is contributed to high-quality productions fish production.


Assuntos
Resposta ao Choque Frio , Perfilação da Expressão Gênica , Animais , Resposta ao Choque Frio/genética , Perfilação da Expressão Gênica/veterinária , Peixes/genética , Fígado/metabolismo , Temperatura Baixa , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Transcriptoma
11.
Chemistry ; : e202304111, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486422

RESUMO

Extracellular vesicles (EVs) carry diverse biomolecules (e. g., nucleic acids, proteins) for intercellular communication, serving as important markers for diseases. Analyzing nucleic acids derived from EVs enables non-invasive disease diagnosis and prognosis evaluation. Membrane fusion, a fundamental cellular process wherein two lipid membranes merge, facilitates cell communication and cargo transport. Building on this natural phenomenon, recent years have witnessed the emergence of membrane fusion-based strategies for the detection of nucleic acids within EVs. These strategies entail the encapsulation of detection probes within either artificial or natural vesicles, followed by the induction of membrane fusion with EVs to deliver probes. This innovative approach not only enables in situ detection of nucleic acids within EVs but also ensures the maintenance of structural integrity of EVs, thus preventing nucleic acid degradation and minimizing the interference from free nucleic acids. This concept categorizes approaches into universal and targeted membrane fusion strategies, and discusses their application potential, and challenges and future prospects.

12.
Rev Esp Enferm Dig ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469826

RESUMO

A previously healthy 39-year-old woman was hospitalized with upper abdominal pain for 1-month duration. A semipedunculated protrusion with smooth surface was found at the gastric angle measuring 2.0 × 2.5-cm by gastroscopy. Endoscopic ultrasound (EUS) showed a hypoechoic mass originated from the mucosal layer. Abdominal computed tomography (CT) revealed a circular pedunculated and slightly low-density mass with mild enhancement in the stomach cavity. Endoscopic submucosal dissection (ESD) was performed. Postoperative histopathology examination revealed the tumor was composed of proliferated spindle cells with eosinophil infiltration which were around small blood vessels and mucosal glands arranged in an "onion-skin" appearance. Immunohistochemical analysis of the spindle cells showed CD34 was positive and CD117, S100, DOG-1, SMA, Desmin were negative. The patient was diagnosed as gastric inflammatory fibroid polyp (IFP) and no symptoms was observed in 12 months follow-up.

13.
Sci Rep ; 14(1): 4507, 2024 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402359

RESUMO

This study explores the factors influencing athletes' compensation satisfaction and their configuration effects. A mixed research approach that combines regression analysis and fuzzy-set qualitative comparative analysis (fsQCA) was applied to process the survey data of 352 athletes from six provinces. The regression analysis results demonstrate that economic compensation, the compensation system, the external environment, and compensation fairness all have a significant positive effect on athletes' compensation satisfaction. Accordingly, the fsQCA approach was applied to explore the combined effects of the factors influencing athletes' compensation satisfaction, which verifies the conclusions drawn from regression analysis and provides improvement paths for increasing athletes' compensation satisfaction.


Assuntos
Atletas , Satisfação Pessoal , Humanos
14.
Zookeys ; 1191: 339-367, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38405678

RESUMO

Six Margattea species are established and described: three are cryptic species, namely, M.parabisignata Li & Che, sp. nov., M.semicircularis Li & Che, sp. nov., and M.forcipata Li & Che, sp. nov. They are distinguished from known species M.bisignata, M.spinifera, and M.paratransversa by their male genitalia with the aid of molecular species delimitation method (ABGD) using COI as the molecular marker. The other three new species are M.pedata Li & Che, sp. nov., M.undulata Li & Che, sp. nov., and M.bisphaerica Li & Che, sp. nov. Morphological and genitalia photographs of these new species of Margattea, as well as a key to the species of Margattea from China, are provided.

15.
Neuroscience ; 543: 28-36, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38382693

RESUMO

Pain symptoms significantly impact the well-being and work capacity of individuals with generalized anxiety disorder (GAD), and hinder treatment and recovery. Despite existing literature focusing on the neural substrate of pain and anxiety separately, further exploration is needed to understand the possible neuroimaging mechanisms of the pain symptoms in GAD patients. We recruited 73 GAD patients and 75 matched healthy controls (HC) for clinical assessments, as well as resting-state functional and structural magnetic resonance imaging scans. We defined a pain-related network through a published meta-analysis, including the insula, thalamus, periaqueductal gray, prefrontal cortex, anterior cingulate cortex, amygdala, and hippocampus. Subsequently, we conducted the regional homogeneity (ReHo) and the gray matter volume (GMV) within the pain-related network. Correlation analysis was then employed to explore associations between abnormal regions and self-reported outcomes, assessed using the Patient Health Questionnaire-15 (PHQ-15) and pain scores. We observed significantly increased ReHo in the bilateral insula but decreased GMV in the bilateral thalamus of GAD compared to HC. Further correlation analysis revealed a positive correlation between ReHo of the left anterior insula and pain scores in GAD patients, while a respective negative correlation between GMV of the bilateral thalamus and PHQ-15 scores. In summary, GAD patients exhibit structural and functional abnormalities in pain-related networks. The enhanced ReHo in the left anterior insula is correlated with pain symptoms, which might be a crucial brain region of pain symptoms in GAD.


Assuntos
Encéfalo , Substância Cinzenta , Humanos , Encéfalo/patologia , Substância Cinzenta/patologia , Córtex Pré-Frontal , Imageamento por Ressonância Magnética/métodos , Transtornos de Ansiedade/diagnóstico por imagem , Dor
16.
Environ Pollut ; 346: 123594, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38378077

RESUMO

In response to the demand for advanced purification of industrial secondary effluent, a new method has been developed for treating chlorophenol wastewater using the novel ceramsite-based Ti/SnO2-Sb particle electrodes (Ti/SnO2-Sb/CB) enhanced electrocatalytic denitrification biofilter (EDNBF-P) to achieve removal of chlorophenols (CPs), denitrification, and reduction of effluent toxicity. The results showed that significantly improved CPs and TN removal efficiency at low COD/N compared to conventional denitrification biofilter, with CPs removal rates increasing by 0.33%-59.27% and TN removal rates increasing by 12.53%-38.92%. Under the conditions of HRT = 2h, 3V voltage, charging times = 12h, and 25 °C, the concentrations of the CPs in the effluent of EDNBF-P were all below 1 mg/L, the TN concentration was below 15 mg/L, while the effluent toxicity reached the low toxicity level. Additionally, the Ti/SnO2-Sb/CB particle electrodes effectively alleviated the accumulation of NO2--N caused by applied voltage. The Silanimonas, Pseudomonas and Rhodobacter was identified as the core microorganism for denitrification and toxicity reduction. This study validated that EDNBF-P could achieve synergistic treatment of CPs and TN through electrocatalysis and microbial degradation, providing a methodological support for achieving advanced purification of chlorophenol wastewater with low COD/N in industrial applications.


Assuntos
Clorofenóis , Misturas Complexas , Microbiota , Águas Residuárias , Desnitrificação , Titânio/química , Eletrodos , Nitrogênio , Reatores Biológicos , Oxirredução
17.
Sci Total Environ ; 922: 171151, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38395160

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are widely used due to their unique structure and excellent performance, while also posing threats on ecosystem, especially long-chain perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). As the control of conventional PFASs, fluoroalkylether substances (ether-PFASs) as alternatives are constantly emerging. Subsequently, the three representative ether-PFASs, chlorinated polyfluoroalkyl ether sulfonic acid (F-53B), hexafluoropropylene oxide-dimer acid (HFPO-DA), and 4,8-Dioxa-3H-perfluorononanoicacid (ADONA) are discovered and have received more attention in the environment and ecosystem. But their security is now also being challenged. This review systematically assesses their security from six dimensions including environmental occurrence in water, soil and atmosphere, as well as bioaccumulation and risk in plants, animals and humans. High substitution level is observed for F-53B, whether in environment or living things. Like PFOS or even more extreme, F-53B exhibits high biomagnification ability, transmission efficiency from maternal to infant, and various biological toxicity effects. HFPO-DA still has a relatively low substitution level for PFOA, but its use has emerged in Europe. Although it is less detected in human bodies and has a higher metabolic rate than PFOA, the strong migration ability of HFPO-DA in plants may pose dietary safety concerns for humans. Research on ADONA is limited, and currently, it is detected in Germany frequently while remaining at trace levels globally. Evidently, F-53B has shown increasing risk both in occurrence and toxicity compared to PFOS, and HFPO-DA is relatively safe based on available data. There are still knowledge gaps on security of alternatives that need to be addressed.


Assuntos
Ácidos Alcanossulfônicos , Caprilatos , Fluorocarbonos , Propionatos , Poluentes Químicos da Água , Animais , Humanos , Bioacumulação , Ecossistema , Fluorocarbonos/análise , Éteres , Etil-Éteres , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental
18.
Nat Commun ; 15(1): 1170, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38326322

RESUMO

SAP05, a secreted effector by the obligate parasitic bacteria phytoplasma, bridges host SPL and GATA transcription factors (TFs) to the 26 S proteasome subunit RPN10 for ubiquitination-independent degradation. Here, we report the crystal structures of SAP05 in complex with SPL5, GATA18 and RPN10, which provide detailed insights into the protein-protein interactions involving SAP05. SAP05 employs two opposing lobes with an acidic path and a hydrophobic path to contact TFs and RPN10, respectively. Our crystal structures, in conjunction with mutagenesis and degradation assays, reveal that SAP05 targets plant GATAs but not animal GATAs dependent on their direct salt-bridged electrostatic interactions. Additionally, SAP05 hijacks plant RPN10 but not animal RPN10 due to structural steric hindrance and the key hydrophobic interactions. This study provides valuable molecular-level information into the modulation of host proteins to prevent insect-borne diseases.


Assuntos
Fatores de Transcrição , Ubiquitina , Ubiquitina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitinação
19.
Sensors (Basel) ; 24(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38339442

RESUMO

As the crucial part of a transmission assembly, the monitoring of the status of the crankshaft is essential for the normal working of a reciprocating machinery system. In consideration of the interaction between crankshaft system components, the fault vibration feature is typically non-stationary and nonlinear, and the single-scale feature extraction method cannot adequately assess the fault features, therefore a novel impact feature extraction method based on genetic algorithms to optimize multi-scale permutation entropy is proposed. Compared with other traditional feature extraction methods, the proposed method illustrates good robustness and high adaptability in the signal processing of crankshaft vibrations. Firstly, the improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN) method is developed on the signal to obtain several intrinsic mode function (IMF) components, and the IMF components with a large kurtosis are selected for array reorganization. Then, the parameters of multi-scale permutation entropy (MPE) are optimized based on genetic algorithm (GA), the multi-scale permutation entropy is calculated and the feature vector set is constructed. The feature vector set is input into the support vector machine (SVM) and optimized by a particle swarm optimization (PSO) model for training and final pattern recognition, where the Variational Mode Decomposition(VMD)-GA-MPE with a PSO-SVM recognition model and the ICEEMDAN-MPE with PSO-SVM recognition model without GA optimization are constructed for a comparison with the proposed method. The research result illustrates that the proposed method, which inputs the genetic algorithm optimized multi-scale permutation entropy extracted from the ICEEMDAN decomposition into the PSO-SVM, performs well in impact feature extraction and the pattern recognition of crankshaft vibrations.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...