The correlates of preschoolers' compliance with screen recommendations exist across multiple domains

Objective:
To investigate the individual, social and physical environment correlates of preschool children's compliance with Australian/Canadian and American Academy of Pediatrics (AAP) screen recommendations.

Method:
An Ecological Model (EM) was used to identify constructs potentially associated with children's screen time. In 2008–2009, parents in Melbourne, Australia, reported their child's screen time and on a range of potential correlates. Children (n = 935; 54% boys, mean age 4.54 ± 0.70 years) were assessed as meeting or not meeting each of the screen recommendations. Logistic regression assessed bivariable and multivariable associations.

Results:
In total, 15 explanatory variables, across the three domains of the EM were associated with boys' and/or girls' compliance with either Australian/Canadian or AAP recommendations. Correlates varied by sex and recommendation. Maternal television viewing time was the only consistent correlate for both boys' and girls' compliance with both recommendations. No demographic groups were identified as being less likely to comply with screen recommendations.

Conclusion:
Public health programs should take account of the sex-specific nature of correlates of preschool children's screen time. Preschool children across all demographic groups need support to engage in less screen use. Parents may benefit from education and parenting skills to minimize potentially harmful effects of excessive screen time for their child.

Maternal and early postnatal nutrition and mental health of offspring by age 5 years: a prospective cohort study clinical guidance

Objective
Diet quality is related to the risk for depression and anxiety in adults and adolescents; however, the possible impact of maternal and early postnatal nutritional exposures on children’s subsequent mental health is unexplored.

Method
The large prospective Norwegian Mother and Child Cohort Study recruited pregnant women between 1999 and 2008. Data were collected from mothers during pregnancy and when children were 6 months and 1.5, 3, and 5 years of age. Latent growth curve models were used to model linear development in children’s internalizing and externalizing problems from 1.5 to 5 years of age as a function of diet quality during pregnancy and at 1.5 and 3 years. Diet quality was evaluated by dietary pattern extraction and characterized as “healthy” or “unhealthy.” The sample comprised 23,020 eligible women and their children. Adjustments were made for variables including sex of the child, maternal depression, maternal and paternal age, maternal educational attainment, household income, maternal smoking before and during pregnancy, mothers’ parental locus of control, and marital status.

Results
Higher intakes of unhealthy foods during pregnancy predicted externalizing problems among children, independently of other potential confounding factors and childhood diet. Children with a high level of unhealthy diet postnatally had higher levels of both internalizing and externalizing problems. Moreover, children with a low level of postnatal healthy diet also had higher levels of both internalizing and externalizing problems.

Conclusion
Among this large cohort of mothers and children, early nutritional exposures were independently related to the risk for behavioral and emotional problems in children.

Health, behavioral, cognitive, and social correlates of breakfast skipping among women living in socioeconomically disadvantaged neighborhoods

Breakfast skipping is a potentially modifiable behavior that has negative effects on health and is socioeconomically patterned. This study aimed to examine the intrapersonal (health, behavioral, and cognitive) and social factors associated with breakfast skipping. Nonpregnant women (n = 4123) aged 18-45 y from socioeconomically disadvantaged neighborhoods throughout Victoria, Australia, completed a postal questionnaire. Sociodemographic characteristics, diet, physical activity, sedentary behaviors, and cognitive and social factors were assessed by self-report. Breakfast skipping was defined in 2 ways: 1) "rarely/never" eating breakfast (n = 498) and 2) eating breakfast ≤2 d/wk (includes those who rarely/never ate breakfast; n = 865). Poisson regression was used to calculate prevalence ratios and linear trends, adjusting for covariates. The P values for linear trends are reported below. Compared with breakfast consumers, women who reported rarely/never eating breakfast tended to have poorer self-rated health (P-trend < 0.001), be current smokers (P-trend < 0.001), pay less attention to health (P-trend < 0.001), not prioritize their own healthy eating when busy looking after their family (P-trend < 0.001), have less nutrition knowledge (P-trend < 0.001), and a lower proportion were trying to control their weight (P-trend < 0.020). When breakfast skipping was defined as eating breakfast ≤2 d/wk, additional associations were found for having lower leisure-time physical activity (P-trend = 0.012) and less self-efficacy for eating a healthy diet (P-trend < 0.043). In conclusion, a range of intrapersonal and social factors were significantly associated with breakfast skipping among women living in socioeconomically disadvantaged areas. Acknowledging the cross-sectional design and need for causal confirmation, programs that aim to promote breakfast consumption in this population group should consider targeting family-related barriers to healthy eating and nutrition knowledge.

Temperature conditions during 'cold' sheet metal stamping

This paper investigates the friction and deformation-induced heating that occurs during the stamping of high strength sheet steels, under room temperature conditions. A thermo-mechanical finite element model of a typical plane strain stamping process was developed to understand the temperature conditions experienced within the die and blank material; and this was validated against experimental measurements. A high level of correlation was achieved between the finite element model and experimental data for a range of operating conditions and parameters. The model showed that the heat generated during realistic production conditions can result in high temperatures of up to 108 °C and 181 °C in the blank and die materials, respectively, for what was traditionally expected to be 'cold' forming conditions. It was identified that frictional heating was primarily responsible for the peak temperatures at the die surface, whilst the peak blank temperatures were caused by a combination of frictional and deformation induced heating. The results provide new insights into the local conditions within the blank and die, and are of direct relevance to sheet formability and tool wear performance during industrial stamping processes. © 2014 Elsevier B.V. All rights reserved.