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101.
The objective was to assess food consumption among children attending non-profit nurseries in the Federal District, Brazil.A representative sample was obtained and stratified by income. Food intake among 678 children, between 4 and 82 months old, was analyzed in nine nurseries using the 24-h dietary recall and direct food weighing methods. In children under 13 months old mean intake was above AI between 93.6 to 100% for carbohydrates, proteins, vitamins B1, B2, B12, B6, and zinc. In children from 7-12 months 56.5% presented iron consumption below EAR. Calcium intake was above AI for 35.4% of children over 1 year old. For vitamins with EAR values, the prevalence of inadequate consumption was 53.2% for vitamin E, and 90% for folate for children over 12 months old. Iron and zinc intake was above UL for 6.4% and 32.5% of children under 1 year old, and 1.5% and 5.3% for the remaining children, respectively. Lipid percentage distribution range among children between 13 and 47 months old was within the acceptable range for only 16.2%. Nonetheless, children between 36 and 82 months of both genders presented mean intake below energy requirements. Inadequate consumption observed for some nutrients points to the need for improvements in the standard of meals and nutritional assistance offered to children enrolled in charitably run nurseries in the Federal District. 相似文献
102.
Andreia G. Macedo Rute A. S. Ferreira Duarte Ananias Mário S. Reis Vitor S. Amaral Luís D. Carlos João Rocha 《Advanced functional materials》2010,20(4):624-634
There is a growing interest in understanding how size‐dependent quantum confinement affects the photoluminescence efficiency, excited‐state dynamics, energy‐transfer and thermalization phenomena in nanophosphors. For lanthanide (Ln3+)‐doped nanocrystals, despite the localized 4f states, confinement effects are induced mostly via electron–phonon interactions. In particular, the anomalous thermalization reported so far for a handful of Ln3+‐doped nanocrystals has been rationalized by the absence of low‐frequency phonon modes. This nanoconfinement may further impact on the Ln3+ luminescence dynamics, such as phonon‐assisted energy transfer or upconversion processes. Here, intriguing and unprecedented anomalous thermalization in Gd2O3:Eu3+ and Gd2O3:Yb3+,Er3+ nanotubes, exhibiting up to one order of magnitude larger than previously reported for similar materials, is reported. This anomalous thermalization induces unexpected energy transfer from Eu3+ C2 to S6 crystallographic sites, at 11 K, and 2H11/2 → 4I15/2 Er3+ upconversion emission; it is interpreted on the basis of the discretization of the phonon density of states, easily tuned by varying the annealing temperature (923–1123 K) in the synthesis procedure, and/or the Ln3+ concentration (0.16–6.60%). 相似文献
103.
Cristhian Carrasco Carlos Solano José Mauricio Peñarrieta Henrique Macedo Baudel Mats Galbe Gunnar Lidén 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(12):1723-1725
A pentose‐rich hydrolysate fraction obtained by extraction of steam‐pretreated sugarcane bagasse was analysed with regard to dissolved phenolics. The liquid obtained after steam pretreatment (2% SO2 (w/w) at 190 °C for 5 min) was divided into two parts: one containing dissolved compounds originating from hemicellulose (with xylose as the dominating compound), and the other containing predominantly dissolved compounds originating from lignin. Using nuclear magnetic resonance, the main dissolved compounds originating from lignin were identified as the glycosylated aromatics, 5‐O‐(trans‐feruloyl)‐L‐Arabinofuranose and 5‐O‐(trans‐coumaroyl)‐L‐Arabinofuranose, together with p‐coumaric acid and small amounts of more common free phenolics such as p‐hydroxybenzaldehyde, p‐hydroxybenzoic acid and vanillin. The phenolic compounds were analysed and quantified using reversed‐phase high‐performance liquid chromatography. The findings show that SO2 steam explosion opened up new degradation pathways during lignin degradation. Copyright © 2012 Society of Chemical Industry 相似文献
104.
105.
ML Mayer SJ Clark TR Konrad VA Freeman RT Slifkin 《Canadian Metallurgical Quarterly》1999,89(2):164-170
OBJECTIVES: This study assessed the influence of public policies on the immunization status of 2-year old children in the United States. METHODS: Up-to-dateness for the primary immunization series was assessed in a national sample of 8100 children from the 1988 National Maternal and Infant Health Survey and its 1991 Longitudinal Follow-Up. RESULTS: Documented immunization rates of this sample were 33% for poor children and 44% for others. More widespread Medicated coverage was associated with greater likelihood of up-to-dateness among poor children. Up-to-dateness was more likely for poor children with public rather than private sources of routine pediatric care, but all children living in states where most immunizations were delivered in the public sector were less likely to be up to date. Poor children in state with partial vaccine replacement programs were less likely to be up to date than those in free-market purchase states. CONCLUSIONS: While state policies can enhance immunization delivery for poor children, heavy reliance on public sector immunization does not ensure timely receipt of vaccines. Public- and private-sector collaboration is necessary to protect children from vaccine-preventable diseases. 相似文献
106.
NP Camacho L Hou TR Toledano WA Ilg CF Brayton CL Raggio L Root AL Boskey 《Canadian Metallurgical Quarterly》1999,14(2):264-272
Osteogenesis imperfecta (OI), a heritable disease caused by molecular defects in type I collagen, is characterized by skeletal deformities and brittle bones. The heterozygous and homozygous oim mice (oim/+ and oim/oim) exhibit mild and severe OI phenotypes, respectively, serving as controlled animal models of this disease. In the current study, bone geometry, mechanics, and material properties of 1-year-old mice were evaluated to determine factors that influence the severity of phenotype in OI. The oim/oim mice exhibited significantly smaller body size, femur length, and moment of area compared with oim/+ and wild-type (+/+) controls. The oim/oim femur mechanical properties of failure torque and stiffness were 40% and 30%, respectively, of the +/+ values, and 53% and 36% of the oim/+ values. Collagen content was reduced by 20% in the oim/oim compared with +/+ bone and tended to be intermediate to these values for the oim/+. Mineral content was not significantly different between the oim/oim and +/+ bones. However, the oim/oim ash content was significantly reduced compared with that of the oim/+. Mineral carbonate content was reduced by 23% in the oim/oim bone compared with controls. Mineral crystallinity was reduced in the oim/oim and oim/+ bone compared with controls. Overall, for the majority of parameters examined (geometrical, mechanical, and material), the oim/+ values were intermediate to those of the oim/oim and +/+, a finding that parallels the phenotypes of the mice. This provides evidence that specific material properties, such as mineral crystallinity and collagen content, are indicative and possibly predictive of bone fragility in this mouse model, and by analogy in human OI. 相似文献
107.
A new approach is proposed to retrace the combined effects of temperature and duration within the thickness of heat-treated Fagus sylvatica wood. Torrefaction is a mild pre-treatment of biomass carried out at 200-300 °C to improve its properties for pulverized systems such as gasification. The properties of wood treated at high temperature are closely related to chemical modifications induced by temperature levels and treatment duration. This study involved the spectral analysis of solid wood in the near infrared range with the aim of developing a predictive model for process assessment. Samples of beech wood were used for calibration under high temperature conditions of 220, 250 and 280 °C for 1 and 8 h. For prediction, a 50-mm thick solid piece of wood was treated at 250 °C for 3 h. It was demonstrated that it is possible not only to distinguish between wood samples that have undergone different heat treatments, but also to retrace the thermal history of a piece of wood. Statistical processing showed the compensatory effects of temperature and duration, along with the existence of an exothermal reaction in the solid piece of wood. It should thus be possible to ensure cheaper and faster quality control in continuous torrefaction processes. 相似文献
108.
K. TRÄDER 《国际可持续能源杂志》2013,32(5):281-295
In 1980, the CEC launched a call for tenders for photovoltaic pilot projects. Since mid 1984, all the relating plants are in operation. In late summer 198S, the WIP has been charged to inspect the PV plants, so as to gather information on the operational status of the systems. This inspection showed that most of the plants are working satisfactorily. Nevertheless, optimization measures are possible for many installations in the field of power management and conditioning systems, data acquisition and recording, battery management and charge controlling, loads and load matching, software, maintenance and documentation. So far, the PV modules themselves, the support structures and batteries have shown to be trouble-free components of PV systems. In order to preserve the potential of the PV plants and make good use of it, the Commission sponsors, in the frame of the current photovoltaic R & D Programme, follow-up activities on the existing installations. 相似文献
109.
1. Growing pullets were reared on constant 8, 11 or 14 h photoperiods or given 12 daily increments of 30 min followed by an abrupt 6 h decrease in photoperiod in 14 d cycles from 2 d of age to sexual maturity. 2. Birds on the experimental lighting programme matured earlier than constant 8-h controls, later than 11-h controls but at the same age and body weight as constant 14-h controls. 3. Weight of the first egg was correlated with age at first egg. 4. It is assumed that potential advances in maturity for the experimental birds from the 30 min increments in photoperiod were cancelled by the retarding influences of 6 h decreases in photoperiod, resulting in their maturity being similar to that of birds reared on a constant daylength equal to the longest photoperiod reached during the cycle. 相似文献
110.