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This study was conducted to investigate the characteristics of the AlCrCuFeNi high-entropy alloy (HEA) synthesized through mechanical alloying (MA). In addition, effects of Process Control Agent (PCA) amount and milling time were investigated using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The results indicated that the synthesized AlCrCuFeNi alloy is a dual phase (FCC + BCC) HEA and the formation of the phases is strongly affected by the PCA amount. A high amount of PCA postponed the alloying process and prevented solid solution formation. Furthermore, with an increase in the PCA amount, lattice strain decreased, crystallite size increased, and the morphology of the mechanically alloyed particles changed from spherical to a plate-like shape. Additionally, investigation of thermal properties and annealing behavior at different temperatures revealed no phase transformation up to 400 °C; however, the amount of the phases changed. By increasing the temperature to 600 °C, a sigma phase (σ) and a B2-ordered solid solution formed; moreover, at 800 °C, the FCC phase decomposed into two different FCC phases.

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Background: Peripherally inserted central catheters (PICCs) are an effective method for medication and nutrition infusion in preterm neonates. The present study aimed to identify the incidence of the most common complications of PICC implantation and evaluate the risk factors of each complication. Methods: This historical cohort study was conducted on 2500 neonates with birth weights (BWs)≥500 g and gestational age (GA)>24 weeks who had a history of PICC inserted in three NICUs between August 2015 and August 2018. Data were collected by reviewing medical records. Demographic data and indices of catheter placement, duration of catheter placement, and common complications were recorded. Data analysis was done using SPSS-21. Results: The median cubital vein had the most PICC placement (43%). The most common complication was tip malposition (48.2%). The incidence rates (95% CI) of the main complications such as malposition, edema/occlusion, and PICC migration were 0.0356 (0.0337-0.0377), 0.0134 (0.0122-0.0147), and 0.0088 (0.0079-0.0099), respectively. PICC insertion position was the strongest predictor of malposition for the cephalic vein. Besides, the incidence of malformation in the cephalic vein was about six times higher than in the median cubital vein. Independent risk factors for non-technical complications included BW (OR=0.59, 95% CI 0.44-0.79), administration of hyperosmolar medications (OR=3.43, 95% CI 2.62-4.51), position (OR=2.43, 95% CI 1.92- 3.08), and duration of catheter presence (OR=1.02, 95% CI 1.01-1.03) (P<0.001). Conclusion: The most common complication was malposition related to catheter placement in an emergency. Moreover, BW, administration of hyperosmolar medications, and duration of catheter presence were the most critical risk factors for non-technical complications. Therefore, it is recommended to educate the PICC insertion team to reduce tip malposition and replace long-term catheters.

Background: Advances in medical science and success in increasing the survival rate of vulnerable infants have raised the future evolution issues of these children. Developmental and behavioral disorders are the most common problem in children after discharge from NICU. A lot of factors are involved in the occurrence of developmental disorders. Objectives: According to the importance of the subject and lack of accurate regional information, this study aimed to investigate the developmental disorders and related factors in low weight infants. Methods: This retrospective cohort study was performed on 76, 4-12 month-old infants with a history of hospitalization in NICU of Shiraz Hazrat Zeinab Hospital with an average weight of 1800 grams. These infants were evaluated developmentally by ASQ (Age and stage questionnaire). The data was analyzed by statistical tests. Results: Using ASQ , 17% of children were detected as having developmental disorders. The percentages of developmental disorders for fine and gross motor domains, problem solving ability, communication and personal-social behaviors were 14.5%, 23.7%, 19.7%, 17.6% and 14.5%, respectively. The correlation coefficient statistical test did not show any significant relationship between developmental disorder with mechanical ventilation, duration of hospitalization, surfactant and betamethasone injection, and final diagnosis of diseases (r < 1). Conclusions: Although improvement in respiratory therapy, monitoring system, non-invasive procedures and developmental care have decreased neonatal mortality rate and prematurity complications, but we cannot find any relationship between related risk factors and neurological outcomes. Developmental delay of low birth weight infants must be detected and rehabilitation started soon after discharge from NICU.

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