Children's School-Day Nutrient Intake in Ontario: A Cross-Sectional Observational Study Comparing Students' Packed Lunches from Two School Schedules.

This study compared the caloric and nutrient values of packed lunch contents and consumption in the Balanced School Day (BSD) (two 20 min eating periods) versus the Traditional Schedule (TS) (one 20 min lunch). Foods consumed during school were assessed by direct food observation in 321 grade 3 and 4 students, aged 7−10 years, at 9 BSD and 10 TS elementary schools in Ontario. Packed lunch contents in the BSD were significantly higher than the TS in energy (3128.14 ± 1100.36 vs. 2658.98 ± 951.34 kJ, p < 0.001, respectively). Similarly, carbohydrates, total sugar, protein, fat, saturated fatty acids (SFA), calcium, iron, and sodium were significantly higher in the BSD versus TS packed lunches. Correspondingly, students in the BSD consumed significantly more energy, carbohydrates, total sugar, and SFA compared to the TS. Overall, lunches brought by students in the BSD schedule provided more energy across all macronutrients, with only a few micronutrients showing increased amounts, suggesting two 20 min eating opportunities could contribute to excess caloric intake during school, potentially contributing to the prevalence of childhood overweight and obesity in Canada. Furthermore, packed lunches in both schedules had excess amounts of nutrients of concern and much work is needed to ensure that children in Canada receive nutritious lunches at school.

Asymptotic Properties of Linear Field Equations in Anti-de Sitter Space.

We study the global dynamics of the wave equation, Maxwell's equation and the linearized Bianchi equations on a fixed anti-de Sitter (AdS) background. Provided dissipative boundary conditions are imposed on the dynamical fields we prove uniform boundedness of the natural energy as well as both degenerate (near the AdS boundary) and non-degenerate integrated decay estimates. Remarkably, the non-degenerate estimates "lose a derivative". We relate this loss to a trapping phenomenon near the AdS boundary, which itself originates from the properties of (approximately) gliding rays near the boundary. Using the Gaussian beam approximation we prove that non-degenerate energy decay without loss of derivatives does not hold. As a consequence of the non-degenerate integrated decay estimates, we also obtain pointwise-in-time decay estimates for the energy. Our paper provides the key estimates for a proof of the non-linear stability of the anti-de Sitter spacetime under dissipative boundary conditions. Finally, we contrast our results with the case of reflecting boundary conditions.

Facilitating barriers: Contextual factors and self-management of type 2 diabetes in urban settings.

Urban environments create unique challenges for the management of type 2 diabetes (T2D). City living is associated with unhealthy occupational, nutritional, and physical activity patterns. However, it has also been linked to behaviours that promote health, such as walking and cycling for transportation. Our research is situated at the intersection of these contradictory findings. We ask: What aspects of urban living impact the ability of those living with diabetes to reach optimal health? What contextual and structural factors influence how barriers are experienced in the everyday lives of those living with T2D? We conducted semi-structured interviews with 29 individuals living in Toronto and Vancouver. Interviews were recorded, transcribed, and systematically coded for themes and sub-themes. In addition to affirming readily acknowledged barriers to diabetes management, such as accessing healthy, culturally appropriate food and the cost of management, our findings suggest that the unpredictable nature of urban living creates barriers to routinizing self-management practices. As large, cosmopolitan centres with an abundance of activities on offer, cities pulls people away from home, making adherence to self-management recommendations more difficult. Moreover, our findings challenge commonly held assumptions about the mutually exclusive and static nature of barriers and facilitators. Public transit, a readily acknowledged facilitator of healthy living, can be experienced as a barrier to diabetes management. Participants report intentional non-adherence to their medication regimens for fear of hypoglycemia in subway or traffic delays. While the stimulating nature of cities promotes walkability, it produces barriers as well: participants partake in more restaurant eating than they would if they lived in a rural area and were home to cook their own meals. Understanding how barriers are experienced by people living with diabetes will help mitigate some of the unintended consequences associated with various contextual factors. We recommend that healthcare professionals acknowledge and support people with T2D in routinizing self-management and developing contingency plans for the unpredictability and complexity that urban living entails. We suggest further research be carried out to develop contextually-tailored municipal policies and interventions that will support self-management and improve outcomes for individuals living with T2D in urban settings.

Parental Reports of Lunch-Packing Behaviours Lack Accuracy: Reported Barriers and Facilitators to Packing School Lunches.

PURPOSE: Parents influence the foods their children consume and often provide proxy reports of this intake. One way parents exert this influence is by providing home-packed lunches. This study compared parental reports of foods packed in children's lunches with what was actually packed and identified parental barriers and facilitators to packing lunches. METHODS: Grade 3 and 4 student-parent dyads (n = 321) in 19 elementary schools in Ontario participated. Parental reports and actual packed lunch contents were collected via self-administered surveys and direct observation, respectively. Parental barriers and facilitators were obtained through open and closed survey questions. RESULTS: Median portions packed were significantly higher for sugar-sweetened beverages and snacks and significantly lower for fruits, fruit juice, vegetables, milk/alternatives, and meat/alternatives than parents reported. Packing a healthy lunch was "important/very important/of the utmost importance" for 95.9% of respondents, and 97.5% perceived their nutrition knowledge as "adequate/good/very good". Barriers to packing a lunch included: child's food preferences, time, finances, allergy policies, and food safety. Nutrition resources, observing other children's lunches, child's input, and planning ahead were identified as facilitators. CONCLUSIONS: Strategies to improve packed lunches should move beyond parental nutrition knowledge and importance of lunch packing to address parental barriers and facilitators.

Students' Food Intake from Home-Packed Lunches in the Traditional versus Balanced School Day.

PURPOSE: To assess the type and quantity of foods children brought and consumed at school in the balanced school day (BSD), with two 20-minute eating periods, versus the traditional schedule (TS), with one 20-minute lunch. METHODS: Direct observation identified food items and amounts in BSD and TS lunches of grade 3 and 4 students (n = 321). RESULTS: The mean (SD) servings of foods packed in BSD lunches were significantly higher than the TS lunches for milk and alternatives (0.69 (0.70) vs 0.47 (0.49), P = 0.02), sugar-sweetened beverages (SSBs; 0.91 (1.24) vs 0.57 (0.99), P = 0.01), and snacks (2.74 (1.55) vs 2.24 (1.48), P < 0.01). Regardless of schedule, only 40.8% of students had vegetables packed in their lunch, whereas 92.8% had snacks. When comparing foods eaten, SSBs and snacks remained significantly higher in the BSD (0.75 (1.02) vs 0.48 (0.83), P = 0.03; 2.37 (1.44) vs 1.93 (1.36), P = 0.01, respectively). The proportion of children (%) whose consumption met one-third of Canada's Food Guide recommendations for vegetables and fruit was low (27.5% BSD, 31.0% TS). CONCLUSIONS: The BSD may have unintended negative consequences on the type and amount of foods packed in school lunches. Support for families should focus on encouraging more vegetables and fruit and fewer SSBs and snacks in packed lunches.