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This paper shows the methodology to assess fracture behaviour in sintered steels. Fracture toughness and the microstructure of PM steel (Fe-4.0Ni-1.5Cu-0.5Mo-0.5C) have been studied as a function of sintered density in a range from 7.20 to 7.51 g/cm³. Highest densities were achieved by warm compaction and double pressing-double sintering using three different lubricants. A quantitative analysis of microstructure was correlated with fracture behavior to assess the influence of pore morphology on mechanical properties. Fracture toughness increased with density, being this performance a remarkable advantage over wrought steels. Results showed that the enhanced behavior of the denser samples is due to improved distribution of more spherical porosity. In spite of using different lubricants, the final results depend solely on sintered density reached by each processing route. [ABSTRACT FROM AUTHOR]

Objective: The main objective of this research was to analyze the feeding practices of infants who attended Mexican Social Security Institute nurseries (IMSS), in two states in Mexico with opposite prevalence of overweight and obesity. Methodology: This was rapid qualitative research through semi structured interviews (n=66) with parents and staff in 14 IMSS day-care centers located in Oaxaca and Yucatan. Results: The feeding process in day-care is structured and homogenized. Awareness and knowledge about each part of the process are perceived in the staff so that the food service is as close to the regulations as possible. Mothers and fathers consider that feeding at nurseries differs from feeding at home. Limitations: This study did not investigate in depth about food control practices that parents or caregivers could exercise, and that affect the formation of habits. Finally, the results and testimonies of this study may not be valid in other population groups. Conclusions: Day-care centers play a crucial role in the development of eating habits of minors, by providing an environment for healthy eating practices and promoting knowledge of new foods. [ABSTRACT FROM AUTHOR]