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61.
The aim of this study was to compare growth curves of stature in indigenous and non-indigenous children belonging to two levels of poverty and to establish the onset and evolution of the deficit. Children of indigenous and non-indigenous background living in communities of extreme and low poverty in Chile were studied and their height-for-age Z-score from birth until 6 year of age were compared. Mean weight at birth was within normal range, and no differences were found in ethnicity and levels of poverty. Length at birth was below the reference with the exception of the non indigenous newborn from counties of low poverty. Deficit in growth showed an early start, furthermore in indigenous children belonging to the extreme poverty, is from birth and progress through the 18 months. At 72 months the deficit reached -1.1 z scores in the indigenous of the extreme poverty versus -0.7 in the non indigenous group. Children from the low poverty had a Z-score of -0.4 z scores at 72 months without differences between ethnias. Indigenous of the extreme poverty had less accumulative growth while the indigenous of the low poverty areas growth satisfactory without differences with the non indigenous.  相似文献   
62.
Many countries are pursuing innovation-led “smart” growth, which requires long-run strategic investments and public policies that aim to create and shape markets, rather than just “fixing” markets or systems. Market creation has characterized the kind of mission-oriented investments that led to putting a man on the moon and are currently galvanizing green innovation. Mission-oriented innovation has required public agencies to not only “de-risk” the private sector, but also to lead the direct creation of new technological opportunities and market landscapes. This paper considers four key issues that arise from a market-creating framework for policy: (1) decision-making on the direction of change; (2) the nature of (public and private) organizations that can welcome the underlying uncertainty and discovery process; (3) the evaluation of mission-oriented and market-creation policies; and (4) the ways in which both risks and rewards can be shared so that smart growth can also result in inclusive growth.  相似文献   
63.
The influence of high intensity pulsed electric fields (HIPEF) treatment (35 kV/cm, bipolar 4 μs square wave pulses at 200 Hz) on the inactivation of Listeria innocua in fruit juice–whole (FJ–WM) or skim milk (FJ–SM) beverages was assessed. As well, the effects of HIPEF or conventional thermal (90 °C 60 s) processing in terms of microbial and enzymatic stability and changes on physicochemical parameters of the beverages during refrigerated storage were also studied. HIPEF and thermal processing ensured the microbial stability of the beverages during 56 days at 4 °C without significant changes on pH, acidity and soluble solid content values. Thermal processing was more effective than HIPEF in reducing Pectin Methyl Esterase (PME) activity in FJ–SM and FJ–WM beverages since its activity was reduced by 70.66% and 87.33%, respectively. With regards to Polygalacturonase (PG), HIPEF treatment reduced by 26.92% and 20.93% the enzyme activity in the FJ–WM and FJ–SM beverages, respectively, whereas thermal treatment did not inactivate PG in both beverages. HIPEF or thermally-treated samples showed higher viscosity than the untreated ones, being this increment more pronounced in the beverages with whole milk. Therefore, HIPEF processing may be a feasible technology in order to obtain shelf stable and fresh-like fruit juice-milk beverages.  相似文献   
64.
Niobium oxides have been reported as an alternative to tantalum, and its oxide, for the production of capacitors, but these materials still require a further and exhaustive study. Understanding the dynamics of the oxidation process from NbO to Nb2O5 is essential to explain and control the properties of a niobium oxide based capacitors. In situ XRD analysis of NbO powders was performed from 100 to 1100 °C, which showed a temperature range where only amorphous phase is present. The capacitor anodes, formed from the same type of NbO powders, were then heat-treated in air from room-temperature (RT) to 550 °C and recorded with a video camera to see the colour shift. The presence of core–shell structures and the increase of the shell thickness/amount with temperature are visible in SEM. Finally, in situ spectroscopy studies were performed, in order to observe the interference spectra which are responsible for the observed colours.  相似文献   
65.
Copper catalysts supported on ceria, zirconia and niobia were prepared by combustion method with urea, containing a CuO loading of 6 wt.%, and tested on selective oxidation of CO. The characterization of the samples by X-ray diffraction (XRD) presented the formation of solid solution on CuO–CeO2 catalyst and a change in crystalline structure of the support with copper insertion on ZrO2 and Nb2O5 catalysts. The analysis of temperature-programmed reduction (TPR) revealed different interaction degrees of copper with the supports, with reduction peaks between 222 and 390 °C. The temperature-programmed desorption of CO (TPD-CO) profiles showed formation of CO2 and H2 only for the ceria and zirconia catalysts. In relation to the catalytic tests, the CuO–CeO2 catalyst presented the best performance, with CO conversion of 95% at 150 °C up to 45 h on stream, and CO2 selectivity of 55%.  相似文献   
66.
The moisture equilibrium isotherms of garlic and apple were determined at 50, 60 and 70 °C using the gravimetric static method. The experimental data were analysed using GAB, BET, Henderson–Thompson and Oswin equations. The isosteric heat and the differential entropy of desorption were determined by applying Clausius–Clapeyron and Gibbs–Helmholtz equations, respectively. The GAB equation showed the best fitting to the experimental data (R2 > 99% and E% < 10%). The monolayer moisture content values for apple were higher than those for garlic at the studied temperatures; the values varied from 0.050 to 0.056 and from 0.107 to 0.168 for garlic and apple, respectively. The isosteric heat and the differential entropy of desorption were estimated in function of the moisture content. The values of these thermodynamic properties were higher for apple (in range 48–100 kJ mol?1 and 14–150 J mol?1 K?1) than for garlic (in range 43–68 kJ mol?1 and 0–66 J mol?1 K?1). The water surface area values decreased with increasing temperature. The Kelvin and the Halsey equations were used to calculate the pore size distribution.  相似文献   
67.
In laser welding technique, a real-time control of temperature distribution inside the irradiated materials is essential when attempting to optimize the process. For all laser welding methods that operate by the transmission principle, the difficulty of recording the developed temperature at the interface derives from the fact that materials to be welded are in contact throughout the entire process. In the present study, in order to overcome this issue, a contact-free method such the infrared thermography is used for surface temperature measurement. Corroborating this data with a numerical simulation of the temperature field evolution inside the components, an assessment of optimal process parameters is possible. The experimental investigations are made on amorphous polymers, in a typical configuration for through-transmission laser welding. The fine agreement obtained between the experimentally and calculated data, validate the infrared thermography as a non-destructive method for real-time monitoring of the welding process.  相似文献   
68.
Four acetostearin products with increasing acetylation degree were synthesized by chemical interesterification followed by fractionation/blending stages. Their physical properties and functional barrier properties were studied and compared to the properties of technical tristearin. Increasing acetylation degree (AD) modified the triacylglycerols crystal habits and probably led to an increase in acyl chain fluidity, which induced, at macroscopic levels, a decrease in solid fat content (SFC), in melting point, in surface and bulk material hydrophobicity, and an increased moisture effective diffusivity. Water vapor permeability (WVP) coefficients of the materials were partially influenced by the AD factor, but also by the development of macroscopic cracks in lipids presenting high SFC. Acetylated stearin up to 47% (acetyl mol/mol of esterified chain) presented the lowest WVP at 20 °C resulting from an adequate balance between hydrophobicity and mechanical properties of the material.  相似文献   
69.
Cross-sectional study with 270 children and their mothers in eight public and philanthropic daycare centers in the city of S?o Paulo, Brazil. The objective is to identify the determinants of exclusive breastfeeding (EBF) and breastfeeding (BF). The Mann-Whitney/ Wilcoxon test and survival analysis; Kaplan Meier curves and Cox multiple regression models were used for statistical analyses. The median of exclusive breastfeeding duration was 79.1 +/- 55.6 days and breastfeeding was 185.3 +/- 174.2 days. In multivariate analysis, the following risk factors of early weaning for exclusive breastfeeding were identified: pacifier use (HR = 1.65, 95% CI = 1.24 to 2.2); previous hospital admission (HR = 1.35, 95% CI = 1.01 to 1.80); mother working outside home (HR = 1.33, 95% CI = 1.00 to 1.76). For breastfeeding were identified: pacifier use (HR = 2.54, 95% CI = 1.87 to 3.45) and mother who works outside the home (HR = 1.51, 95% CI = 1.14-1.99). The results show that it is necessary to continue to promote and support breastfeeding, mainly the exclusive breastfeeding until six months of age. The daycare centers should incorporate this idea, once they may have direct control over some of the early weaning determinants, and are also good places to deliver messages and guidance on nutrition education to mothers and caregivers in contact with children under three years old.  相似文献   
70.
A mutant of D ‐fructose‐6‐phosphate aldolase (FSA) of Escherichia coli, FSA A129S, with improved catalytic efficiency towards dihydroxyacetone (DHA), the donor substrate in aldol addition reactions, was explored for synthetic applications. The kcat/KM value for DHA was 17‐fold higher with FSA A129S than that with FSA wild type (FSA wt). On the other hand, for hydroxyacetone as donor substrate FSA A129S was found to be 3.5‐fold less efficient than FSA wt. Furthermore, FSA A129S also accepted glycolaldehyde (GA) as donor substrate with 3.3‐fold lower affinity than FSA wt. This differential selectivity of both FSA wt and FSA A129S for GA makes them complementary biocatalysts allowing a control over donor and acceptor roles, which is particularly useful in carboligation multi‐step cascade synthesis of polyhydroxylated complex compounds. Production of the mutant protein was also improved for its convenient use in synthesis. Several carbohydrates and nitrocyclitols were efficiently prepared, demonstrating the versatile potential of FSA A129S as biocatalyst in organic synthesis.  相似文献   
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