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In this study, the effect of cooling rate on microstructure and impression creep behaviour of the as-cast Al–3.7 wt.% Cu alloy was investigated. Impression creep was performed in the temperature range of 423–513 K in stresses of 380–470 MPa for about 5000 s and cooled with different rates. It is deduced that for all cooling rates, lattice, pipe diffusion and climb controlled dislocation creep control the creep rate. The activation energies vary between 82 and 124 kJ/mol which is due to changing the diffusion mechanism from pipe to lattice self diffusion. Moreover, secondary dendritic arm spacing decreases with increasing the cooling rate because of higher constitutional undercooling and formation of secondary dendrite arms. In this research, an artificial neural networks (ANN) structure was proposed to estimate creep of a cast aluminium alloy. Results show that the ANN is a robust approach to predict the creep behaviour of this alloy. [ABSTRACT FROM PUBLISHER]

Background: Hearing loss is one of the most common congenital disorders. The Early Diagnosis and Intervention Process is designed for the early diagnosis and intervention of hearing loss in infants. The present study aimed to examine the results of Early Hearing Detection and Intervention (EHDI) in northeastern Iran from 2005 to 2019., Setting: Northeastern Iran., Methods: In most cases, the two-stage protocol (otoacoustic emissions [OAE] and automated auditory brainstem response [AABR]) has been used. Infant assessment methods included the use of OAE, ABR, auditory steady-state response, high-frequency tympanometry, and behavioral audiometry. Interventions included medical interventions, hearing rehabilitation, hearing aids, and cochlear implants., Results: 1,162,821 infants were screened. The screening coverage increased from less than 1% in 2005 to about 99% in 2018. The referral rate has been about 1%. 2.17 out of every 1000 infants are hearing impaired, and the most common cases are bilateral hearing loss and mild to moderate hearing loss., Conclusions: During 2005 to 2019 the coverage rate reached to more than 95% of live births. To improve the EHDI process in this population, better follow-up of diagnosed neonates and expansion of diagnostic and intervention services are needed., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 International Journal of Preventive Medicine.)