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1.
Sci Rep ; 14(1): 6303, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491172

RESUMO

Induction skull melting (ISM) technology could melt metals with avoiding contamination from crucible. A long-standing problem of ISM is that the low charge energy utilization and inhomogeneous fields have obstructed its application in many critical metal materials and manufacturing processes. The present work investigated the problem through the structure optimization strategy and established a numerical electromagnetic-field model to evaluate components' eddy current loss. Based on the model, the effect of crucible and inductor structure on charge energy utilization, etc. was studied. Furtherly, the charge energy utilization was increased from 27.1 to 45.89% by adjusting the system structure. Moreover, structure modifications are proposed for enhancing electromagnetic intensity and uniformity, charge soft contact and uniform heating. The work constructed a basis for framing new solutions to the problem through ISM device structure optimization.

3.
Front Psychol ; 12: 681753, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970177

RESUMO

Objectives: To identify the optimal factor structure of the behavioral inhibition system/behavioral activation system (BIS/BAS) scales and to examine measurement invariance (MI) of the scales across gender among a sample of Chinese undergraduate students. Methods: Convenience sampling was employed to recruit 1,085 subjects. Participants completed the Chinese version of the BIS/BAS scales. A confirmatory factor analysis (CFA) of competing models was conducted to determine the optimal factor model, followed by a test of MI across gender based on the optimal model. Results: A single-group CFA indicated that the modified four-factor structure fits best in the total sample. Multiple-group CFAs demonstrated that configural invariance, weak invariance, strong invariance, and strict invariance models of the four-factor structure of the BIS/BAS scales were all acceptable. Conclusion: The four-factor structure of the Chinese version of the BIS/BAS scales possesses MI across gender.

4.
Front Neurosci ; 15: 653325, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994929

RESUMO

Interhemispheric connectivity of the two cerebral hemispheres is crucial for a broad repertoire of cognitive functions including music and language. Congenital amusia has been reported as a neurodevelopment disorder characterized by impaired music perception and production. However, little is known about the characteristics of the interhemispheric functional connectivity (FC) in amusia. In the present study, we used a newly developed voxel-mirrored homotopic connectivity (VMHC) method to investigate the interhemispheric FC of the whole brain in amusia at resting-state. Thirty amusics and 29 matched participants underwent a resting-state functional magnetic resonance imaging (fMRI) scanning. An automated VMHC approach was used to analyze the fMRI data. Compared to the control group, amusics showed increased VMHC within the posterior part of the default mode network (DMN) mainly in the posterior superior temporal gyrus (pSTG) and posterior cingulate cortex (PCC). Correlation analyses revealed negative correlations between the VMHC value in pSTG/PCC and the music perception ability among amusics. Further ROC analyses showed that the VMHC value of pSTG/PCC showed a good sensibility/specificity to differentiate the amusics from the controls. These findings provide a new perspective for understanding the neural basis of congenital amusia and imply the immature state of DMN may be a credible neural marker of amusia.

5.
Neuropsychologia ; 156: 107833, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33757844

RESUMO

Congenital amusia is as a neurodevelopment disorder primarily defined by impairment in pitch discrimination and pitch memory. Interestingly, it has been reported that individuals with congenital amusia also exhibit deficits in face recognition (prosopagnosia). One explanation of such comorbidity is that the neural substrates of pitch recognition and face recognition may be similar. To test this hypothesis, face recognition ability was assessed using the Cambridge Face Memory Test (CFMT) and gray matter volume was determined through voxel-based morphometry (VBM) among participants with and without congenital amusia. As expected, participants with amusia performed worse on the CFMT test and showed reduced gray matter volume (GMV) in the middle temporal gyrus (MTG), the superior temporal gyrus (STG), and the posterior cingulate cortex (PCC) in the right hemisphere, when compared with matched controls. Furthermore, correlation analyses demonstrated that the CFMT score was positively related to MTG, STG, and PCC GMV in all participants, while separate analyses of each group found a positive correlation of CFMT score and PCC GMV in amusics. These findings suggest that face recognition is associated with a widely distributed microstructural network in the human brain and the PCC plays an important role in both pitch recognition and face recognition in amusics. In addition, neurodevelopmental disorders such as congenital amusia and prosopagnosia may share a common neural substrate.


Assuntos
Transtornos da Percepção Auditiva , Reconhecimento Facial , Música , Transtornos da Percepção Auditiva/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Humanos , Discriminação da Altura Tonal , Percepção da Altura Sonora
6.
Neural Regen Res ; 16(3): 531-536, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32985483

RESUMO

Perceiving pitch is a central function of the human auditory system; congenital amusia is a disorder of pitch perception. The underlying neural mechanisms of congenital amusia have been actively discussed. However, little attention has been paid to the changes in the motor rain within congenital amusia. In this case-control study, 17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed. A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control group. We found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls, indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback network. We found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia scores. In conclusion, our study identified novel, hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital amusia. Our evidence supports the view that sensorimotor coupling plays an important role in memory and musical discrimination. The study was approved by the Ethics Committee of the Second Xiangya Hospital, Central South University, China (No. WDX20180101GZ01) on February 9, 2019.

7.
Front Psychiatry ; 12: 721720, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095585

RESUMO

Background: Congenital amusia (CA) is a rare disorder characterized by deficits in pitch perception, and many structural and functional magnetic resonance imaging studies have been conducted to better understand its neural bases. However, a structural magnetic resonance imaging analysis using a surface-based morphology method to identify regions with cortical features abnormalities at the vertex-based level has not yet been performed. Methods: Fifteen participants with CA and 13 healthy controls underwent structural magnetic resonance imaging. A surface-based morphology method was used to identify anatomical abnormalities. Then, the surface parameters' mean value of the identified clusters with statistically significant between-group differences were extracted and compared. Finally, Pearson's correlation analysis was used to assess the correlation between the Montreal Battery of Evaluation of Amusia (MBEA) scores and surface parameters. Results: The CA group had significantly lower MBEA scores than the healthy controls (p = 0.000). The CA group exhibited a significant higher fractal dimension in the right caudal middle frontal gyrus and a lower sulcal depth in the right pars triangularis gyrus (p < 0.05; false discovery rate-corrected at the cluster level) compared to healthy controls. There were negative correlations between the mean fractal dimension values in the right caudal middle frontal gyrus and MBEA score, including the mean MBEA score (r = -0.5398, p = 0.0030), scale score (r = -0.5712, p = 0.0015), contour score (r = -0.4662, p = 0.0124), interval score (r = -0.4564, p = 0.0146), rhythmic score (r = -0.5133, p = 0.0052), meter score (r = -0.3937, p = 0.0382), and memory score (r = -0.3879, p = 0.0414). There was a significant positive correlation between the mean sulcal depth in the right pars triangularis gyrus and the MBEA score, including the mean score (r = 0.5130, p = 0.0052), scale score (r = 0.5328, p = 0.0035), interval score (r = 0.4059, p = 0.0321), rhythmic score (r = 0.5733, p = 0.0014), meter score (r = 0.5061, p = 0.0060), and memory score (r = 0.4001, p = 0.0349). Conclusion: Individuals with CA exhibit cortical morphological changes in the right hemisphere. These findings may indicate that the neural basis of speech perception and memory impairments in individuals with CA is associated with abnormalities in the right pars triangularis gyrus and middle frontal gyrus, and that these cortical abnormalities may be a neural marker of CA.

8.
Front Psychol ; 11: 767, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32499735

RESUMO

BACKGROUND: Screening for secondary traumatic stress (STS) is lacking in China. It is unclear whether Western models of STS can be adapted satisfactorily for use in non-Western regions. The 20-item Secondary Trauma Questionnaire (STQ) is a self-report measure of traumatic stress symptoms in individuals who have been influenced indirectly by suicide or violent injury of people important to the respondents. METHODS: Here, we assessed the psychometric properties of a newly developed Chinese version of the STQ in a potentially traumatized sample (N = 875) composed of doctors, nurses, teachers, civic administration staff, and social workers in China. We performed reliability and validity analyses. Subsequently, we split the total sample into two subsamples for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) for measurement invariance analyses. RESULTS: The full scale demonstrated good internal consistency (Cronbach's α = 0.95-0.97), convergent validity, discriminant validity, and factorial validity. CFA affirmed a one-factor structure; the configural, metric, scalar, and strict invariances of the STQ were acceptable across genders. CONCLUSION: The present results indicate that the STQ is a reliable and valid self-report assessment for use with potentially traumatized people in China, and further supports the notion that the STQ is amenable to additional future cross-cultural adaptation.

10.
Front Psychol ; 11: 247, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210869

RESUMO

The Depression Anxiety Stress Scale-21 (DASS-21) is an instrument in the assessment of mental health status. The current study recruited 1,532 Chinese hospital workers [74.4% female; mean age = 31.97 (SD = 9.70) years] to examine the reliability, latent structure, and measurement invariance of the DASS-21 between genders. The Cronbach's α values were greater than 0.90 for total score. This study examined four possible models of the DASS-21 using the confirmatory factor analysis (CFA) in Chinese hospital workers. The results from CFA revealed that the latent structure of the DASS-21 in medical staffs is best represented by a one-factor model. Then we used the one-factor model to examine measurement invariance across genders by using a multiple-group categorical CFA. All values of root mean square error approximation (RMSEA) were less than 0.08, all Comparative Fix Index (CFI) and Tucker-Lewis Index values were greater than 0.90, all ΔCFI (changes in CFI) values were less than 0.010, and ΔRMSEA (the changes in RMSEA) were less than 0.015. These findings supported the gender invariance of the DASS-21 among Chinese hospital workers.

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