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1.
BMC Public Health ; 23(1): 828, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147646

RESUMO

BACKGROUND: Previous studies showed the adverse impacts of air pollution on headache attacks in developed countries. However, evidence is limited to the impact of exposure to air pollutants on headache attacks. In this study, we aimed to explore the impact of nitrogen dioxide (NO2) exposure on neurology clinic visits (NCVs) for headache onsets. METHODS: Records of NCVs for headaches, concentrations of ambient NO2, and meteorological variables were collected in Wuhan, China, from January 1st, 2017, to November 30th, 2019. A time-series study was conducted to investigate the short-term effects of NO2 exposure on daily NCVs for headaches. Stratified analyses were also computed according to season, age, and sex, and the exposure-response (E-R) curve was then plotted. RESULTS: A total of 11,436 records of NCVs for headaches were enrolled in our study during the period. A 10-µg/m3 increase of ambient NO2 corresponded to a 3.64% elevation of daily NCVs for headaches (95%CI: 1.02%, 6.32%, P = 0.006). Moreover, females aged less than 50 years of age were more susceptible compared to males (4.10% vs. 2.97%, P = 0.007). The short-term effects of NO2 exposure on daily NCVs for headaches were stronger in cool seasons than in warm seasons (6.31% vs. 0.79%, P = 0.0009). CONCLUSION: Our findings highlight that short-term exposure to ambient NO2 positively correlated with NCVs for headaches in Wuhan, China, and the adverse effects varied by season, age, and sex.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Assistência Ambulatorial , China/epidemiologia , Cefaleia/induzido quimicamente , Cefaleia/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise
2.
J Acoust Soc Am ; 153(1): 487, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36732232

RESUMO

In this study, an acoustic leaky-wave antenna (LWA) with heterogeneous structure is proposed and the functions of the spatial directional radiation and acoustic source localization are achieved via utilizing the presented antenna configuration. In the radiating mode, the designed antenna possesses peculiar frequency-scanning characteristics, which enable it to determine the directional radiation of sound waves with diverse incident frequencies. Considering the receiving mode, the antenna emerges with explicit directional frequency characteristics, which ensure its function of spatial acoustic source localization. Additionally, compared with the traditional acoustic LWA, the proposed antenna structure exhibits sharper directivity and has potential applications in high-precision acoustic source localization.

3.
J Acoust Soc Am ; 153(2): 812, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36859138

RESUMO

A theoretical solution of the acoustic radiation force (ARF) on spherical particles by an arbitrary beam in viscous fluids in a tube is proposed. Based on the parametric design with the purpose of promoting calculi in the urinary system, theoretical solutions and finite element simulations are carried out, which mutually confirm the accuracy and feasibility of the scheme. The variation law of the ARF with adjustable parameters, such as incident angle, frequency spectrum, particle radius, tube radius, and viscosity, is studied, and the mechanism of the variation law is explained. This solution lays a foundation for the application of non-contact and non-invasive in-tube manipulation based on ARF in medicine and life sciences.

4.
Plant Dis ; 107(8): 2506-2508, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36774571

RESUMO

Streptomyces atratus PY-1 exhibited promising antimicrobial properties; in particular, it is highly inhibitory to Plasmopara viticola, which causes downy mildew of grape. It is very necessary to carry out systematic and in-depth research on the PY-1 strain for the improvement, application, and promotion of biocontrol agents. The PY-1 genome was fully sequenced and assembled. We present the draft genome sequence of PY-1, with a size of 9, 254, and 781 bp. Preliminary analysis on the PY-1 genome sequence shows that at least 35 gene clusters are involved in the biosynthesis of polyketides, terpenes, and nonribosomally synthesized peptides.


Assuntos
Anti-Infecciosos , Oomicetos , Peronospora , Doenças das Plantas/genética , Oomicetos/genética , Anti-Infecciosos/farmacologia
5.
Emerg Radiol ; 30(2): 217-223, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36626029

RESUMO

Soft tissue necrosis can occur at different tissue levels, with numerous underlying causes. In this pictorial review, we highlight myonecrosis, and its accompanying stages, fat necrosis, devitalized soft tissue seen with infection, and necrotizing soft tissue infections. Imaging examples are provided with each entity.


Assuntos
Doenças Musculares , Infecções dos Tecidos Moles , Humanos , Necrose , Infecções dos Tecidos Moles/diagnóstico por imagem
6.
Sensors (Basel) ; 23(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37631650

RESUMO

The surface defects on a shield subway tunnel can significantly affect the serviceability of the tunnel structure and may compromise operation safety. To effectively detect multiple surface defects, this study uses a tunnel inspection trolley (TIT) based on the mobile laser scanning technique. By conducting an inspection of the shield tunnel on a metro line section, various surface defects are identified with the TIT, including water leakage defects, dislocation, spalling, cross-section deformation, etc. To explore the root causes of the surface defects, association rules between different defects are calculated using an improved Apriori algorithm. The results show that: (i) there are significant differences in different association rules for various surface defects on the shield tunnel; (ii) the average confidence of the association rule "dislocation & spalling → water leakage" is as high as 57.78%, indicating that most of the water leakage defects are caused by dislocation and spalling of the shield tunnel in the sections being inspected; (iii) the weakest rule appears at "water leakage → spalling", with an average confidence of 13%. The association analysis can be used for predicting the critical defects influencing structural reliability and operation safety, such as water leakage, and optimizing the construction and maintenance work for a shield subway tunnel.

7.
Int J Mol Sci ; 24(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37373495

RESUMO

The connexin gene family is the most prevalent gene that contributes to hearing loss. Connexins 26 and 30, encoded by GJB2 and GJB6, respectively, are the most abundantly expressed connexins in the inner ear. Connexin 43, which is encoded by GJA1, appears to be widely expressed in various organs, including the heart, skin, the brain, and the inner ear. The mutations that arise in GJB2, GJB6, and GJA1 can all result in comprehensive or non-comprehensive genetic deafness in newborns. As it is predicted that connexins include at least 20 isoforms in humans, the biosynthesis, structural composition, and degradation of connexins must be precisely regulated so that the gap junctions can properly operate. Certain mutations result in connexins possessing a faulty subcellular localization, failing to transport to the cell membrane and preventing gap junction formation, ultimately leading to connexin dysfunction and hearing loss. In this review, we provide a discussion of the transport models for connexin 43, connexins 30 and 26, mutations affecting trafficking pathways of these connexins, the existing controversies in the trafficking pathways of connexins, and the molecules involved in connexin trafficking and their functions. This review can contribute to a new way of understanding the etiological principles of connexin mutations and finding therapeutic strategies for hereditary deafness.


Assuntos
Surdez , Perda Auditiva , Recém-Nascido , Humanos , Conexina 26/metabolismo , Conexina 43/metabolismo , Conexinas/genética , Conexinas/metabolismo , Surdez/metabolismo , Perda Auditiva/metabolismo , Junções Comunicantes/metabolismo , Mutação
8.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762513

RESUMO

Salicylic acid (SA) serves as a pivotal plant hormone involved in regulating plant defense mechanisms against biotic stresses, but the extent of its biological significance in relation to peanut resistance is currently lacking. This study elucidated the involvement of salicylic acid (SA) in conferring broad-spectrum disease resistance in peanuts through the experimental approach of inoculating SA-treated leaves. In several other plants, the salicylate hydroxylase genes are the typical susceptible genes (S genes). Here, we characterized two SA hydroxylase genes (AhS5H1 and AhS5H2) as the first S genes in peanut. Recombinant AhS5H proteins catalyzed SA in vitro, and showed SA 5-ydroxylase (S5H) activity. Overexpression of AhS5H1 or AhS5H2 decreased SA content and increased 2,5-DHBA levels in Arabidopsis, suggesting that both enzymes had a similar role in planta. Moreover, overexpression of each AhS5H gene increased susceptibility to Pst DC3000. Analysis of the transcript levels of defense-related genes indicated that the expression of AhS5H genes, AhNPR1 and AhPR10 was simultaneously induced by chitin. Overexpression of each AhS5H in Arabidopsis abolished the induction of AtPR1 or AtPR2 upon chitin treatment. Eventually, AhS5H2 expression levels were highly correlated with SA content in different tissues of peanut. Hence, the expression of AhS5H1 and AhS5H2 was tissue-specific.


Assuntos
Arabidopsis , Arachis , Arachis/genética , Arabidopsis/genética , Quitina , Resistência à Doença/genética , Ácido Salicílico/farmacologia
9.
J Prosthet Dent ; 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35589448

RESUMO

This technique enables the establishment of an accurate reciprocation distance to resist undesirable forces on abutments and ensure the parallelism of removable partial denture placement on the guide template by using computer-aided design and computer-aided manufacture techniques and to ensure accurate abutment preparation.

10.
Phys Rev Lett ; 127(8): 084301, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477409

RESUMO

In this Letter, we theoretically propose and experimentally demonstrate a three-dimensional soundproof acoustic cage structure, hereby denoted as an acoustic metacage. The metacage is composed of six acoustic metamaterial slabs with open holes and hidden bypass space coiling tunnels connected to the holes. Band structure analysis reveals a novel physical mechanism to open a low-frequency broad partial band gap via the band folding in other directions, which can also be interpreted by an effective medium with indefinite effective mass density and negative effective modulus. Transmission loss in simulations and in the acoustic impedance tube are administered. Strikingly, we prove that the soundproofing effect of the metacage is robust against the airflow perturbation induced by a fan. Our work paves a road for low-frequency airborne soundproof structures in the presence of ventilation.

11.
BMC Pediatr ; 21(1): 24, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413203

RESUMO

BACKGROUND: Telomeres play a crucial role in cellular survival and its length is a predictor for onset of chronic non-communicable diseases. Studies on association between telomeres and obesity in children have brought discrepant results and the underlying mechanisms and influential factors are to be elucidated. This study aimed to investigate changes in telomere length and telomerase reverse transcriptase (TERT) DNA methylation, and further to determine their correlation with n-3 polyunsaturated fatty acids (PUFAs) in preschool children with obesity. METHODS: Forty-six preschool children with obesity aged 3 to 4 years were included in the study, with equal numbers of age- and gender-matched children with normal weight as control. Leukocyte telomere length was determined by the ratio of telomeric product and single copy gene obtained using real-time qPCR. DNA methylation of TERT promoter was analyzed by bisulfite sequencing. Fatty acids in erythrocytes were measured by gas chromatography with a total of 15 fatty acids analyzed. The total saturated fatty acids (SFAs), total n-6 PUFAs, total n-3 PUFAs, and the ratio of arachidonic acid (AA) to docosahexaenoic acid (DHA) were calculated. Then the correlation between leukocyte telomere length, TERT promoter methylation and fatty acids was determined. RESULTS: In preschool children with obesity, leukocyte telomeres were shortened and had a negative association with the body mass index. The methylated fractions in 13 of 25 CpG sites in the TERT promoter were increased by approximately 3 to 35% in the children with obesity compared to the normal weight children. Erythrocyte lauric acid and total SFAs, lenoleic acid and total n-6 PUFAs were higher, and DHA was lower in the children with obesity than those in the children with normal weight. Correlative analysis showed that leukocyte telomere length had a positive association with total SFAs and DHA, and a negative association with the AA/DHA ratio. However, no association between erythrocyte DHA and the TERT promoter methylation was found. CONCLUSION: These data indicate that the reduced body DHA content and increased AA/DHA ratio may be associated with shortened leukocyte telomeres in child obesity, which is probably not involved in the TERT promoter methylation.


Assuntos
Ácidos Graxos Ômega-3 , Obesidade Infantil , Telomerase , Pré-Escolar , Metilação de DNA , Humanos , Obesidade Infantil/genética , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo
12.
Neural Plast ; 2021: 6151973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335733

RESUMO

Genetic testing is the gold standard for exploring the etiology of congenital hearing loss. Here, we enrolled 137 Chinese patients with congenital hearing loss to describe the molecular epidemiology by using 127 gene panel testing or 159 variant testing. Sixty-three deaf children received 127 gene panel testing, while seventy-four patients received 159 variant testing. By use of 127 gene panel testing, more mutant genes and variants were identified. The most frequent mutant genes were GJB2, SLC26A4, MYO15A, CDH23, and OTOF. By analyzing the patients who received 127 gene panel testing, we found that 51 deaf children carried variants which were not included in 159 variant testing. Therefore, a large number of patients would be misdiagnosed if only 159 variant testing is used. This study highlights the advantage of 127 gene panel testing, and it suggests that broader genetic testing should be done to identify the genetic etiology of congenital hearing loss.


Assuntos
Surdez/diagnóstico , Testes Genéticos , Perda Auditiva Neurossensorial/diagnóstico , Mutação , Criança , Surdez/genética , Feminino , Perda Auditiva Neurossensorial/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Programas de Rastreamento
13.
Neural Plast ; 2021: 9957712, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093702

RESUMO

Congenital deafness is one of the most common causes of disability in humans, and more than half of cases are caused by genetic factors. Mutations of the MYO15A gene are the third most common cause of hereditary hearing loss. Using next-generation sequencing combined with auditory tests, two novel compound heterozygous variants c.2802_2812del/c.5681T>C and c.5681T>C/c.6340G>A in the MYO15A gene were identified in probands from two irrelevant Chinese families. Auditory phenotypes of the probands are consistent with the previously reported for recessive variants in the MYO15A gene. The two novel variants, c.2802_2812del and c.5681T>C, were identified as deleterious mutations by bioinformatics analysis. Our findings extend the MYO15A gene mutation spectrum and provide more information for rapid and precise molecular diagnosis of congenital deafness.


Assuntos
Surdez/genética , Miosinas/genética , Adolescente , Povo Asiático , Criança , Pré-Escolar , Biologia Computacional , Surdez/congênito , Surdez/diagnóstico por imagem , Feminino , Genes Recessivos , Testes Genéticos , Testes Auditivos , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Mutação/genética , Linhagem , Fenótipo , Tomografia Computadorizada por Raios X
14.
Eur Biophys J ; 49(2): 155-161, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006056

RESUMO

Previous studies have shown that alterations in the mechanical properties of cells may be associated with the onset and progression of some forms of pathology. In this paper, an experimental study of two types of cells, renal (cancer) and bladder (cancer) cells, is described which used acoustic radiation force (ARF) generated by a high-frequency ultrasound focusing transducer and performed on the operating platform of an inverted light microscope. Comparing images of cancer cells with those of normal cells of the same kind, we find that the cancer cells are more prone to deform than normal cells of the same kind under the same ARF. In addition, cancer cells with higher malignancy are more deformable than those with lower malignancy. This means that the deformability of cells may be used to distinguish diseased cells from normal ones, and more aggressive cells from less aggressive ones, which may provide a more rapid and accurate method for clinical diagnosis of urological disease in the future.


Assuntos
Acústica , Neoplasias Renais/diagnóstico por imagem , Rim/citologia , Ultrassom , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/citologia , Algoritmos , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Rim/efeitos da radiação , Neoplasias Renais/fisiopatologia , Fenômenos Mecânicos , Transdutores , Bexiga Urinária/efeitos da radiação , Neoplasias da Bexiga Urinária/fisiopatologia
15.
Neural Plast ; 2020: 9260807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908492

RESUMO

Waardenburg syndrome (WS), also known as auditory-pigmentary syndrome, is the most common cause of syndromic hearing loss. It is responsible for 2-5% of congenital deafness. WS is classified into four types depending on the clinical phenotypes. Currently, pathogenic mutation of PAX3, MITF, EDNRB, EDN3, SNAI2, or SOX10 can cause corresponding types of WS. Among them, SOX10 mutation is responsible for approximately 15% of type II WS or 50% of type IV WS. We report the case of a proband in a Chinese family who was diagnosed with WS type II. Whole exome sequencing (WES) of the proband detected a novel heterozygous spontaneous mutation: SOX10 c.246delC. According to analysis based on nucleic acid and amino acid sequences, this mutation may produce a truncated protein, with loss of the HMG structure domain. Therefore, this truncated protein may fail to activate the expression of the MITF gene, which regulates melanocytic development and plays a key role in WS. Our finding expands the database of SOX10 mutations associated with WS and provides more information regarding the molecular mechanism of WS.


Assuntos
Mutação , Fatores de Transcrição SOXE/genética , Síndrome de Waardenburg/genética , Povo Asiático/genética , Criança , China , Humanos , Masculino , Linhagem , Sequenciamento do Exoma
16.
Neural Plast ; 2020: 3569359, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508908

RESUMO

Jervell and Lange-Nielsen syndrome (JLNS) is a rare but severe autosomal recessive disease characterized by profound congenital deafness and a prolonged QTc interval (greater than 500 milliseconds) in the ECG waveforms. The prevalence of JLNS is about 1/1000000 to 1/200000 around the world. However, exceed 25% of JLNS patients suffered sudden cardiac death with kinds of triggers containing anesthesia. Approximately 90% of JLNS cases are caused by KCNQ1 gene mutations. Here, using next-generation sequencing (NGS), we identified a compound heterozygosity for two mutations c.1741A>T (novel) and c.477+5G>A (known) in KCNQ1 gene as the possible pathogenic cause of JLNS, which suggested a high risk of cardiac events in a deaf child. The hearing of this patient improved significantly with the help of cochlear implantation (CI). But life-threatening arrhythmias occurred with a trigger of anesthesia after the end of the CI surgery. Our findings extend the KCNQ1 gene mutation spectrum and contribute to the management of deaf children diagnosed with JLNS for otolaryngologists (especially cochlear implant teams).


Assuntos
Síndrome de Jervell-Lange Nielsen/genética , Canal de Potássio KCNQ1/genética , Mutação , Povo Asiático , Pré-Escolar , China , Análise Mutacional de DNA , Surdez/genética , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Síndrome de Jervell-Lange Nielsen/fisiopatologia , Masculino , Linhagem
17.
Neural Plast ; 2019: 9765276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827501

RESUMO

Auditory neuropathy spectrum disorder (ANSD), also called auditory neuropathy (AN), is a unique type of prelingual hearing impairment. Up to 10% of deaf infants and children are affected by this disease. Mutation of the OTOF gene which encodes otoferlin is the common cause of congenital nonsyndromic ANSD. To date, over 110 mutations have been identified in the OTOF gene according to the Human Gene Mutation Database (HGMD). Here, next-generation sequencing (NGS) revealed that the compound heterozygous mutations c.4748G>A/c.2523+1G>T and c.5248G>C/c.5098G>C of the OTOF gene were present in two Chinese ANSD patients. Each patient had a known pathogenic mutation (c.4748G>A or c.5098G>C) and a novel mutation (c.2523+1G>T or c.5248G>C). Comparative amino acid sequence analysis across different species revealed that the residues at these novel mutation sites are evolutionarily highly conservative. This indicated that the novel mutations were possible causes of the disorder in the patients. Our findings extend the OTOF mutation spectrum and further confirm the role of the OTOF gene in ANSD.


Assuntos
Povo Asiático/genética , Perda Auditiva Central/diagnóstico , Perda Auditiva Central/genética , Heterozigoto , Proteínas de Membrana/genética , Mutação/genética , Sequência de Aminoácidos , Feminino , Testes Auditivos/métodos , Humanos , Lactente , Masculino , Linhagem
18.
J Acoust Soc Am ; 145(4): 2453, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31046378

RESUMO

The purpose of this work is to find a method to locate the scattering centers in spatial domain; by using this information, the mean scatter spacing (MSS) can be estimated, and the spatial information is the one-dimensional imaging of scattering centers. This paper presents a method that can locate the scattering centers in spatial domain robustly and automatically. By incorporating it with fast Fourier transformation, the MSS can be estimated. The three foremost processes, matched filtering, envelope extraction, and peak reconstruction, are incorporated in the authors' algorithm. Monte Carlo simulations demonstrate that the proposed method is a robust one to locate scattering centers in spatial domain, and has a better performance than spectrum-based MSS estimation techniques. Especially exploited in estimating MSS which varies from 0.6 to 1.2 mm in the range of human mean trabecular bone spacing, the proposed method shows great potential in medical use. Simple but widely used phantom experiments demonstrate that the proposed algorithm has the capacity to locate scattering centers in spatial domain.


Assuntos
Modelos Teóricos , Localização de Som , Ondas Ultrassônicas , Condução Óssea , Osso Esponjoso/fisiologia , Análise de Fourier , Humanos , Razão Sinal-Ruído
19.
Sensors (Basel) ; 19(24)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835556

RESUMO

Slab track is widely used in many newly built high-speed rail (HSR) lines as it offers many advantages over ballasted tracks. However, in actual operation, slab tracks are subjected to operational and environmental factors, and structural damages are frequently reported. One of the most critical problems is temperature-induced slab-warping deformation (SWD) which can jeopardize the safety of train operation. This paper proposes an automatic slab deformation detection method in light of the track geometry measurement data, which are collected by high-speed track geometry car (HSTGC). The characteristic of track vertical irregularity is first analyzed in both time and frequency domain, and the feature of slab-warping phenomenon is observed. To quantify the severity of SWD, a slab-warping index (SWI) is established based on warping-sensitive feature extraction using discrete wavelet transform (DWT). The performance of the proposed algorithm is verified against visual inspection recorded on four sections of China HSR line, which are constructed with the China Railway Track System II (CRTSII) slab track. The results show that among the 24,806 slabs being assessed, over 94% of the slabs with warping deformation can be successfully identified by the proposed detection method. This study is expected to provide guidance for efficiently detecting and locating slab track defects, taking advantage of the massive track inspection data.

20.
Sensors (Basel) ; 19(18)2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31540129

RESUMO

For high-speed trains, out-of-roundness (OOR)/defects on wheel tread with small radius deviation may suffice to give rise to severe damage on both vehicle components and track structure when they run at high speeds. It is thus highly desirable to detect the defects in a timely manner and then conduct wheel re-profiling for the defective wheels. This paper presents a wayside fiber Bragg grating (FBG)-based wheel condition monitoring system which can detect wheel tread defects online during train passage. A defect identification algorithm is developed to identify potential wheel defects with the monitoring data of rail strain response collected by the devised system. In view that minor wheel defects can only generate anomalies with low amplitude compared with the wheel load effect, advanced signal processing methods are needed to extract the defect-sensitive feature from the monitoring data. This paper explores a Bayesian blind source separation (BSS) method to decompose the rail response signal and to obtain the component that contains defect-sensitive features. After that, the potential defects are identified by analyzing anomalies in the time history based on the Chauvenet's criterion. To verify the proposed defect detection method, a blind test is conducted using a new train equipped with defective wheels. The results show that all the defects are identified and they concur well with offline wheel radius deviation measurement results. Minor defects with a radius deviation of only 0.06 mm are successfully detected.

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