881,118 research outputs found
Some hypersonic intake studies
A 'two dimensional' air intake comprisipg a wedge followed by an isentropic compression has been tested in the Cranfield Gun Tunnel at Mach 8,2. These tests were performed to investigate qualitatively the intake flow starting process. The effects of cowl position, Reynolds number, boundary-layer trip and introduction of a small restriction in the intake duct were investigated. Schlieren pictures of the flow on the compression surface and around the intake entrance were taken. Results showed that the intake would operate over the Reynolds number range tested. Tests with a laminar boundary layer demonstrated the principal influence of the Reynolds number on the boundary-layer growth and consequently on the flow structure in the intake entrance. In contrast boundary layer tripping produced little variation in flow pattern over the Reynolds number range tested. The cowl lip position appeared to have a strong effect on the intake performance. The only parameter which prevented the intake from starting was the introduction of a restriction in the intake duct. The experimental data obtained were in good qualitative agreement with the CFD predictions. Finally, these experimental results indicated a good intake flow starting process over multiple changes of parameters
The Relationship between Zinc Intake and Serum/Plasma Zinc Concentration in Children: A Systematic Review and Dose-Response Meta-Analysis
Recommendations for zinc intake during childhood vary widely across Europe. The EURRECA project attempts to consolidate the basis for the definition of micronutrient requirements, taking into account relationships among intake, status and health outcomes, in order to harmonise these recommendations. Data on zinc intake and biomarkers of zinc status reported in randomised controlled trials (RCTs) can provide estimates of dose-response relationships which may be used for underpinning zinc reference values. This systematic review included all RCTs of apparently healthy children aged 1–17 years published by February 2010 which provided data on zinc intake and biomarkers of zinc status. An intake-status regression coefficient was calculated for each individual study and calculated the overall pooled and SE using random effects meta-analysis on a double log scale. The pooled dose-response relationship between zinc intake and zinc status indicated that a doubling of the zinc intake increased the serum/plasma zinc status by 9%. This evidence can be utilised, together with currently used balance studies and repletion/depletion studies, when setting zinc recommendations as a basis for nutrition policies
Usual energy and macronutrient intakes in 2-9-year-old European children
OBJECTIVE: Valid estimates of population intakes are essential for monitoring trends as well as for nutritional interventions, but such data are rare in young children. In particular, the problem of misreporting in dietary data is usually not accounted for. Therefore, this study aims to provide accurate estimates of intake distributions in European children.
DESIGN: Cross-sectional setting-based multi-centre study.
SUBJECTS: A total of 9560 children aged 2-9 years from eight European countries with at least one 24-h dietary recall (24-HDR).
METHODS: The 24-HDRs were classified in three reporting groups based on age- and sex-specific Goldberg cutoffs (underreports, plausible reports, overreports). Only plausible reports were considered in the final analysis (N=8611 children). The National Cancer Institute (NCI)-Method was applied to estimate population distributions of usual intakes correcting for the variance inflation in short-term dietary data.
RESULTS: The prevalence of underreporting (9.5%) was higher compared with overreporting (3.4%). Exclusion of misreports resulted in a shift of the energy and absolute macronutrient intake distributions to the right, and further led to the exclusion of extreme values, that is, mean values and lower percentiles increased, whereas upper percentiles decreased. The distributions of relative macronutrient intakes (% energy intake from fat/carbohydrates/proteins) remained almost unchanged when excluding misreports. Application of the NCI-Method resulted in markedly narrower intake distributions compared with estimates based on single 24-HDRs. Mean percentages of usual energy intake from fat, carbohydrates and proteins were 32.2, 52.1 and 15.7%, respectively, suggesting the majority of European children are complying with common macronutrient intake recommendations. In contrast, total water intake (mean: 1216.7 ml per day) lay below the recommended value for >90% of the children.
CONCLUSION: This study provides recent estimates of intake distributions of European children correcting for misreporting as well as for the daily variation in dietary data. These data may help to assess the adequacy of young children's diets in Europe
Cruciferous vegetable intake and cardiovascular disease risk in the Framingham Offspring Cohort
Fruit and vegetable intake has been demonstrated to be inversely correlated with CVD risk, but it remains to be elucidated whether different subclasses of fruits and vegetables and their bioactive constituents have different effects on CVD risk. Cruciferous vegetables have garnered increasing attention over the years, as evidence for their protective role in cancer and other chronic diseases has grown. However, since studies examining associations between cruciferous vegetable intake and cardiovascular disease (CVD) are limited and some results are conflicting, we used data from the Framingham Offspring Study starting with examination 5 (N=2902) to evaluate the association between cruciferous vegetable intake and carefully adjudicated cardiovascular outcomes, cruciferous vegetable consumption was classified into 4 categories; <1, 1-<3, 3-<6, and 6+ one-half cup servings per week. Cox proportional hazard models were used to adjust for potential confounding; the final model contained baseline BMI, age, smoking status, alcohol intake (drinks per day), total fruit and vegetable intake, and trans fatty acid intake. Follow up continued for three consecutive 4-year exam cycles. Using <1.0 serving/week as the referent category, the hazard ratios (HR) for CVD declined in a dose-response manner with cruciferous vegetable intake (HR: 0.79, 95% CI: 0.64-0.98; HR: 0.78, 95% CI: 0.61-1.01; and HR: 0.66, 95% CI: 0.45-0.98, respectively. In sex-stratified analysis, the strongest effects were found in men consuming 6+ servings per week (HR: 0.49, 95% CI: 0.24 – 0.98). HR estimates also declined in women, but with less of a dose-response pattern. Overall, these data suggests that there is an inverse association between cruciferous vegetable intake and CVD risk in both men and women
Linoleic acid intake, plasma cholesterol and 10-year incidence of CHD in 20.000 middle-aged men and women in the Netherlands
We studied the associations of a difference in linoleic acid or carbohydrate intake with plasma cholesterol levels and risk of CHD in a prospective cohort study in the Netherlands. Data on diet (FFQ) and plasma total and HDL-cholesterol were available at baseline (1993–7) of 20 069 men and women, aged 20–65 years, who were initially free of CVD. Incidence of CHD was assessed through linkage with mortality and morbidity registers. During an average of 10 years of follow-up, 280 CHD events occurred. The intake of linoleic acid ranged from 3·6 to 8·0 % of energy (en%), whereas carbohydrate intake ranged from 47·6 to 42·5 en% across quintiles of linoleic acid intake. Linoleic acid intake was inversely associated with total cholesterol and HDL-cholesterol in women but not in men. Linoleic acid intake was not associated with the ratio of total to HDL-cholesterol. No association was observed between linoleic acid intake and CHD incidence, with hazard ratios varying between 0·83 and 1·00 (all P>0·05) compared to the bottom quintile. We conclude that a 4–5 en% difference in linoleic acid or carbohydrate intake did not translate into either a different ratio of total to HDL-cholesterol or a different CHD incidenc
Optimal distribution and utilization of donated human breast milk: a novel approach
Background: The nutritional content of donated expressed breast milk (DEBM) is variable. Using DEBM to provide for the
energy requirements of neonates is challenging.
Objective: The authors hypothesized that a system of DEBM energy content categorization and distribution would improve
energy intake from DEBM.
Methods: We compared infants’ actual cumulative energy intake with projected energy intake, had they been fed using our
proposed system. Eighty-five milk samples were ranked by energy content. The bottom, middle, and top tertiles were classified
as red, amber, and green energy content categories, respectively. Data on 378 feeding days from 20 babies who received this
milk were analyzed. Total daily intake of DEBM was calculated in mL/kg/day and similarly ranked. Infants received red energy
content milk, with DEBM intake in the bottom daily volume intake tertile; amber energy content milk, with intake in the middle
daily volume intake tertile; and green energy content milk when intake reached the top daily volume intake tertile.
Results: Actual median cumulative energy intake from DEBM was 1612 (range, 15-11 182) kcal. Using DEBM with the
minimum energy content from the 3 DEBM energy content categories, median projected cumulative intake was 1670 (range
13-11 077) kcal, which was not statistically significant (P = .418). Statistical significance was achieved using DEBM with the
median and maximum energy content from each energy content category, giving median projected cumulative intakes of 1859
kcal (P = .0006) and 2280 kcal (P = .0001), respectively.
Conclusion: Cumulative energy intake from DEBM can be improved by categorizing and distributing milk according to
energy content
The relationship between zinc intake and serum/plasma zinc concentration in adults: a systematic review and dose–response meta-analysis by the EURRECA Network
Dietary zinc recommendations vary widely across Europe due to the heterogeneity of pproaches used by expert panels. Under the EURRECA consortium a protocol was designed to systematically review and undertake meta-analyses of research data to create a database that includes “best practice” guidelines which can be used as a resource by future panels when setting micronutrient recommendations. As part of this process, the objective of the present study was to undertake a systematic review and meta-analysis of previously published data describing the relationship between zinc intake and status in adults. Searches were performed of literature published up to February 2010 using MEDLINE, Embase, and Cochrane Library. Data extracted included population characteristics, dose of zinc, duration of study, dietary intake of zinc, and mean concentration of zinc in plasma or serum at the end of the intervention period. An intake-status regression coefficient was estimated for each individual study, and pooled meta-analysis undertaken. The overall pooled for zinc supplementation on serum/plasma zinc concentrations from RCTs and observational studies was 0.08 (95% CI 0.05, 0.11; p<0.0001; I2 84.5%). An overall of 0.08 means that for every doubling in zinc intake, the difference in zinc serum or plasma concentration is (20.08 = 1.06), which is 6%. Whether the dose-response relationship, as provided in this paper, could be used as either qualitative or quantitative evidence to substantiate the daily zinc intake dose necessary to achieve normal or optimal levels of biomarkers for zinc status, remains a matter of discussion
Food Intake, Diet Quality and Behavioral Problems in Children: Results from the GINI-plus/LISA-plus Studies
Background/Aims: To assess the association between food intake and diet quality and behavioral problems at the 10-year follow-up of the two population-based birth cohorts of the studies German Infant Nutritional Intervention and `Influences of lifestyle-related factors on the immune system and the development of allergies in childhood'. Methods: Cross-sectional data on food intake over the past year were collected by a parent-reported food frequency questionnaire. Diet quality was based on reference values of food amounts of the optimized mixed diet. Behavioral problems were assessed by a parent-reported Strengths and Difficulties Questionnaire. Relationships between food category intake, diet quality and behavior problems were examined using multivariable regression modeling adjusted for gender, sociodemographic characteristics, body mass index, physical exercise, television viewing/PC use and total energy intake. A total of 3,361 children with complete data were analyzed. Results: Children with increased intake of confectionery had increased odds of having emotional symptoms {[}adjusted odds ratio (ORadj) 1.19, 95% confidence interval (CI) 1.08-1.32] compared to children with low intake. A higher diet quality score was associated with lower likelihood of emotional symptoms (ORadj 0.89, 95% CI 0.80-0.98). The un-adjusted significant relationship between diet quality and hyperactivity/inattention was attenuated by adjusting for several confounders to an ORadj of 0.92 (95% CI 0.82-1.03). Conclusions: Increased consumption of high-sugar products and lower diet quality are associated with a higher likelihood of emotional symptoms in children. Copyright (C) 2012 S. Karger AG, Base
Food Calorie Intake under Grain Price Uncertainty: Evidence from Rural Nepal
This study evaluates the effects of grain output price uncertainty on the farm income of rural households and, consequently, how this uncertainty influences caloric intake through changes in farm income. Using a rural household data set, augmented with output price uncertainty measures calculated from historical time-series data, we find that grain output price uncertainty tends to decrease crop production income of rural households. In addition, we find that higher crop income from production increases calorie intake of rural households. Taken together, these results suggests that output price uncertainty during the production process may tend to reduce caloric intake of rural Nepalese households since the price uncertainty negatively affects the crop income households need to buy calorie-rich staple foods.Food Calorie Intake, Price Uncertainty, Nepal, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, D12, O13, Q11, Q12,
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