OBJECTIVEIn order to accurately reconstruct the acoustic source image, the application of transducer's receiving characteristics in magneto-acoustic tomography with magnetic induction (MAT-MI) is studied.

METHODSThe conductivity phantom model is built, and the magnetic acoustic signals are simulated and the acoustic sources are reconstructed according to the transducer's receiving characteristics.

RESULTSThe reconstructed image of acoustic source is consistent with the topographic shape and size of the phantom model.

CONCLUSIONMAT-MI based on the transducer's characteristics lays the foundation for further study.

Acoustics ; Magnetic Phenomena ; Magnetics ; Tomography ; Transducers

An improved algorithm of histogram equalization for image enhancement is discussed. After the image containing noises was wavelets transformed, the low frequency wavelet coefficients are equalized, and then all the wavelets are inverse transformed to enhance the image. This improved algorithm of histogram equalization gets a better image enhancement effect by test verification.

Objective In order to accurately reconstruct the acoustic source image, the application of transducer’s receiving characteristics in magneto-acoustic tomography with magnetic induction (MAT-MI) is studied. Methods The conductivity phantom model is built, and the magnetic acoustic signals are simulated and the acoustic sources are reconstructed according to the transducer’s receiving characteristics. Results The reconstructed image of acoustic source is consistent with the topographic shape and size of the phantom model. Conclusion MAT-MI based on the transducer’s characteristics lays the foundation for further study.

Objective:To explore the status of post-traumatic growth and meaning in life among family caregivers of the disabled elderly in the community, and to analyze the correlation between the two.Methods:From August 2019 to August 2020, convenience sampling was used to select 560 family caregivers of the disabled elderly in the community of Guangzhou as the research object. The General Information Questionnaire, Posttraumatic Growth Inventory (PTGI) and the Chinese Meaning in Life Questionnaire (C-MLQ) were used for the investigation. Pearson correlation and hierarchical regression were used to analyze the correlation between post-traumatic growth and meaning in life in family caregivers of the disabled elderly. A total of 560 questionnaires were distributed, and 526 valid questionnaires were recovered after excluding incomplete questionnaires and answering questionnaires according to a certain rule.Results:The total scores of PTGI and C-MLQ of 526 family caregivers of the disabled elderly were (49.43±20.43) and (42.96±7.61) , respectively. The total score of PTGI and the scores of each dimension were positively correlated with the total score of C-MLQ and the two dimensions of meaning experience and meaning pursuit ( P<0.01) . The hierarchical regression showed that, after controlling for general data, both meaning experience and meaning pursuit could positively predict post-traumatic growth. Conclusions:Post-traumatic growth of family caregivers of disabled elderly is at low level. Family caregivers' meaning in life has a positive effect on post-traumatic growth. Community workers should strengthen the meaning in life education, help caregivers to effectively cope with traumatic events, improve the level of post-traumatic growth, and promote mental health.