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1.
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.

2.
Dysphagia ; 37(5): 1271-1278, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34826007

RESUMO

The current study sought to examine longitudinal changes of dysphagia in Parkinson's disease, identify predictors of dysphagia aggravation and elucidate the influence of dysphagia on other symptoms in Parkinson's disease patients. Forty-eight patients with Parkinson's disease were enrolled. All patients underwent videofluoroscopic study of swallowing evaluation and a battery of neuropsychological assessments at baseline in 2014 and at follow-up in 2020. We used t-tests or Wilcoxon tests for comparative analysis between patients with/without dysphagia and comparative analysis of longitudinal data. We used Spearman's correlation analysis to examine predictors of dysphagia aggravation, and the Wilcoxon test to compare neuropsychological aggravation between patients with/without dysphagia at baseline. Swallowing function, cognitive function, depression, anxiety, and quality of life were aggravated at follow-up. Dysphagia prevalence increased from 27.08 at baseline to 39.58% at follow-up. Spearman's correlation results showed that dysphagia was more likely to become aggravated in male patients compared with female patients (P = 0.0049). Cognitive impairment at baseline was significantly related to dysphagia aggravation (P = 0.042). Patients with dysphagia at baseline exhibited a significantly greater increase in anxiety scores than patients without dysphagia at baseline (P = 0.021). The results revealed that male sex and cognitive impairment predicted worsening dysphagia in Parkinson's disease patients, and suggested that dysphagia may have a negative impact on anxiety in Parkinson's disease patients. The results highlight the importance of swallowing function screening and necessary instrumental checks, such as videofluoroscopic study of swallowing, in Parkinson's disease patients.


Assuntos
Transtornos de Deglutição , Doença de Parkinson , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Feminino , Seguimentos , Humanos , Masculino , Doença de Parkinson/complicações , Qualidade de Vida
3.
Dysphagia ; 34(4): 600-607, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31037327

RESUMO

Dysphagia is a common non-primary symptom of patients with Parkinson's disease. The aim of this study is to investigate the underlying alterations of brain functional connectivity in Parkinson's disease patients with dysphagia by resting-state functional magnetic resonance imaging. We recruited 13 Parkinson's disease patients with dysphagia and ten patients without dysphagia, diagnosed by videofluoroscopic study of swallowing. Another 13 age and sex-matched healthy subjects were recruited. Eigenvector centrality mapping was computed to identify functional connectivity alterations among these groups. Parkinson's disease patients with dysphagia had significantly increased functional connectivity in the cerebellum, left premotor cortex, the supplementary motor area, the primary motor cortex, right temporal pole of superior temporal gyrus, inferior frontal gyrus, anterior cingulate cortex and insula, compared with patients without dysphagia. This study suggests that functional connectivity changes in swallowing-related cortexes might contribute to the occurrence of dysphagia in Parkinson's disease patients.


Assuntos
Encéfalo/fisiopatologia , Transtornos de Deglutição/etiologia , Rede Nervosa/fisiopatologia , Doença de Parkinson/complicações , Doença de Parkinson/etiologia , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/fisiopatologia , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia
4.
Eur Spine J ; 26(7): 1862-1870, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28281005

RESUMO

BACKGROUND: Postural deformities in the coronal plane were frequent and disabling complications of PD, which reduces the quality of life of patients. This study aimed to garner greater attention to the Parkinson disease (PD)-related postural trunk deviations in the coronal plane by exploring a method for diagnosis because of the lack of any uniform diagnostic criteria and epidemiological studies. It also aimed to provide correlation data in the Chinese PD patients. METHODS: In this cross-sectional study, 503 consecutive outpatients with PD were enrolled who underwent standardized clinical evaluation. The study recruited 83 PD patients diagnosed with Pisa syndrome (PS). Scoliosis and coronal imbalance were diagnosed accurately by radiographic data. The PD patients were compared based on the Cobb angle and coronal balance for several demographic and clinical variables. RESULTS: PD patients with PS had a prevalence of 16.5%. The prevalence of coronal imbalance and scoliosis was 10.34 and 7.75%, respectively. PD patients with PS were older and had a more severe disease, significantly longer disease duration and treatment duration, and reduced quality of life. The most important finding was that the different morphology of the spinal level had an effect on the severity of coronal balance or Cobb angle. CONCLUSIONS: The present study indicated that the postural deformities in the coronal plane were related to the morphology of the spinal level, especially the position of the Cobb angle. To benefit the PD patients with PS, the full-length standing spine radiographs should be performed as early as possible.


Assuntos
Doença de Parkinson/complicações , Escoliose/diagnóstico , Escoliose/etiologia , Idoso , China , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Radiografia , Fatores de Risco , Escoliose/epidemiologia
5.
Mov Disord ; 31(11): 1704-1710, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27613677

RESUMO

OBJECTIVE: Familial cortical myoclonic tremor with epilepsy is a rare epilepsy syndrome. Herein, we report on nine Chinese familial cortical myoclonic tremor with epilepsy pedigrees to delineate its clinical and neurophysiological features. METHODS: Detailed clinical and neurophysiological data were obtained. Somatosensory evoked potential amplitudes and clinical profile were analyzed using multilevel statistical models. Age-at-onset anticipation was analyzed using Kaplan-Meier survival analysis. RESULTS: Fifty-five patients were interviewed directly, whose mean age at onset of cortical tremor and generalized tonic-clonic seizures were 31.0 ± 8.3 and 36.0 ± 7.9 years. Giant somatosensory evoked potential was detected in 87.5% (28 of 32) of patients, and long-latency cortical reflex was detected in 93.5% (29 of 31). Cortical tremor severity was significantly higher in patients with longer disease duration of cortical tremor (P = 0.0061). Somatosensory evoked potential amplitudes were significant higher in patients with higher level of cortical tremor severity (P = 0.0003) and those using antiepileptic drugs (P = 0.0150). Age-at-onset anticipation of cortical tremor with paternal transmission was found with statistical significance (P = 0.022). CONCLUSION: We provided the clinical and neurophysiological features of familial cortical myoclonic tremor with epilepsy patients. This study is reported for the presentation of this rare disease in a Chinese population with the largest single report on familial cortical myoclonic tremor with epilepsy worldwide. Age-at-onset anticipation of cortical tremor with paternal transmission was statistically significant, which further confirmed a possibility of unstable expanding repeat in the genetic mechanism of familial cortical myoclonic tremor with epilepsy. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Antecipação Genética , Córtex Cerebral/fisiopatologia , Epilepsias Mioclônicas/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Adolescente , Adulto , Idade de Início , Idoso , China , Epilepsias Mioclônicas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Adulto Jovem
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 81(1): 44-7, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21737343

RESUMO

The characteristics of host-guest complexation between tetrabutyl ether derivatives of p-sulfonatocalix[4]arene (SC4Bu) and methiocarb [3,5-dimethyl-4-(methylthio) phenyl methylcarbamate] were investigated by fluorescence spectrometry. Upon addition of methiocarb, the fluorescence intensity of SC4Bu was quenched regularly and a slight red shift was observed for the maximum emission peak. These results indicated that the SC4Bu-methiocarb complex was formed a 1:1 mole ratio. An association constant of 1.67×10(4) L mol(-1) was calculated by applying a deduced equation. The interaction mechanism of the inclusion complex was discussed. Based on the results, a novel spectrofluorimetric method was described for the determination of methiocarb with a detection limit at 0.05 µg mL(-1). This method is very simple and shows high sensitivity and selectivity. Moreover, the proposed method was successfully applied to the determination of methiocarb in water samples.


Assuntos
Calixarenos/química , Calixarenos/farmacologia , Metiocarb/análise , Fenóis/química , Fenóis/farmacologia , Interações Medicamentosas , Modelos Biológicos , Modelos Moleculares , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos , Tensoativos/química , Tensoativos/farmacologia , Termodinâmica
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