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41.
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
42.
JosA. Castillo Christine Gurard‐Hlaine Mariana Gutirrez Xavier Garrabou Martine Sancelme Melanie Schürmann Tomoyuki Inoue Virgil Hlaine Franck Charmantray Thierry Gefflaut Laurence Hecquet Jesús Joglar Pere Claps GeorgA. Sprenger Marielle Lemaire 《Advanced Synthesis \u0026amp; Catalysis》2010,352(6):1039-1046
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
43.
44.
Anna Raffaela de Matos Costa Juliana Cysneiros Lima Raquel dos Santos Lhaira Souza Barreto Mariana Alves Henrique Laura Hecker de Carvalho Yêda Medeiros Bastos de Almeida 《应用聚合物科学杂志》2021,138(36):50916
This work deals with the rheological, morphological, and thermal properties of composites having poly(ethylene terephthalate) (PET), polyamide-6 (PA6), and their blends as matrices, and rice husk ash (RHA) as a filler. The study determines the effect of composition on the change in viscosity and rate of degradation during processing in a torque rheometer. Our data indicates that thermal stability and degradation during processing depend on matrix composition and filler concentration. SEM micrographs show both partial adhesion of the filler to the matrices and filler pullout. Optical microscopy shows particle agglomeration and that agglomerate size increased with filler content. FTIR investigates the shifting of absorption bands of PET/PA6 composite after the addition of RHA and attributes the selective dispersion of RHA to the formation of hydrogen bonds. Our data supports the idea that filler employed here is an option to develop polymer composites with improved properties. 相似文献
45.
Mariana Fatobene Ando Sindy Fuhrmann Zhiwen Pan Bruno Poletto Rodrigues Tatsuya Mori Stefan G. Ebbinghaus Katrin Wondraczek Suguru Kitani Lothar Wondraczek 《Journal of the American Ceramic Society》2021,104(10):4991-5000
We use low-temperature heat capacity, low-frequency Raman scattering, and THz time domain spectroscopy in order to scale the vibrational density of states and the Boson peak in SiO2-Al2O3-B2O3 Yb-laser host glasses. When substituting B2O3 for SiO2 at constant Al2O3 dopant level, we find an optimal value for the ratio of B/Al in terms of mixture stability, at which the excess in the electron donor capability of Al2O3 (relative to the SiO2 backbone) is compensated by the more acidic B2O3. At this composition, Al2O3 plays a mediating role in the structure of aluminoborosilicate glasses, facilitating dissolution of Yb2O3 and admixture of B2O3 into the SiO2 network. 相似文献
46.
Tiago Morais Alexandre L. Seabra Brbara G. Patrício Marta Guimares Mrio Nora Pedro F. Oliveira Marco G. Alves Mariana P. Monteiro 《International journal of molecular sciences》2021,22(11)
Visceral adipose tissue (VAT) metabolic profiling harbors the potential to disentangle molecular changes underlying obesity-related dysglycemia. In this study, the VAT exometabolome of subjects with obesity and different glycemic statuses are analyzed. The subjects (n = 19) are divided into groups according to body mass index and glycemic status: subjects with obesity and euglycemia (Ob+NGT, n = 5), subjects with obesity and pre-diabetes (Ob+Pre-T2D, n = 5), subjects with obesity and type 2 diabetes under metformin treatment (Ob+T2D, n = 5) and subjects without obesity and with euglycemia (Non-Ob, n = 4), used as controls. VATs are incubated in culture media and extracellular metabolite content is determined by proton nuclear magnetic resonance (1H-NMR). Glucose consumption is not different between the groups. Pyruvate and pyroglutamate consumption are significantly lower in all groups of subjects with obesity compared to Non-Ob, and significantly lower in Ob+Pre-T2D as compared to Ob+NGT. In contrast, isoleucine consumption is significantly higher in all groups of subjects with obesity, particularly in Ob+Pre-T2D, compared to Non-Ob. Acetate production is also significantly lower in Ob+Pre-T2D compared to Non-Ob. In sum, the VAT metabolic fingerprint is associated with pre-diabetes and characterized by higher isoleucine consumption, accompanied by lower acetate production and pyruvate and pyroglutamate consumption. We propose that glucose metabolism follows different fates within the VAT, depending on the individuals’ health status. 相似文献
47.
Magossi Maiara S. Maraldi Vitor A. Magossi Mariana S. DA Costa Fabíola M. Alves Kamilla Franco Fernanda D. S. DO Carmo Devaney R. 《SILICON》2021,13(7):2243-2255
Silicon - This study describes the preparation and characterization of 3-chloropropyl silica gel with 4-amino-5-(4pyridyl)-4H-1,2,4-triazole-3-thiol (SGA) for copper adsorption in different media.... 相似文献
48.
This study is the result of ongoing research for a European Union 7th Framework Program Project regarding energy converters for very low heads, and aims to analyze optimization of new cost-effective hydraulic turbine designs for possible implementation in water supply systems (WSSs) or in other pressurized water pipe infrastructures, such as irrigation, wastewater, or drainage systems. A new methodology is presented based on a theoretical, technical and economic analysis. Viability studies focused on small power values for different pipe systems were investigated. Detailed analyses of alternative typical volumetric energy converters were conducted on the basis of mathematical and physical fundamentals as well as computational fluid dynamics (CFD) associated with the interaction between the flow conditions and the system operation. Important constraints (e.g., size, stability, efficiency, and continuous steady flow conditions) can be identified and a search for alternative rotary volumetric converters is being conducted. As promising cost-effective solutions for the coming years, adapted rotor-dynamic turbomachines and non-conventional axial propeller devices were analyzed based on the basic principles of pumps operating as turbines, as well as through an extensive comparison between simulations and experimental tests. 相似文献
49.
Hristo M. Najdenski Liliana G. Gigova Ivan I. Iliev Plamen S. Pilarski Jaromir Lukavský Iva V. Tsvetkova Mariana S. Ninova Vesselin K. Kussovski 《International Journal of Food Science & Technology》2013,48(7):1533-1540
In vitro activity of nine cyanobacterial and ten microalgal newly isolated or culture collection strains against eight significant food‐borne pathogens has been evaluated and compared. Water extracts and culture liquids of Gloeocapsa sp. and Synechocystis sp. demonstrated the widest spectrum of activity with minimal inhibitory concentration (MIC) ranging from 1.56 to 12.5 mg mL?1. Culture liquid of Anabaena sp. had the highest activity (MIC = 0.39 mg mL?1) but only to Gram‐positive bacteria. Ethanol extracts and fatty acids from all cyanobacteria and microalgae were active against Streptococcus pyogenes and/or Staphylococcus aureus. The fatty acids of Synechocystis sp. inhibited the growth of Bacillus cereus, Escherichia coli and Candida albicans (MIC values of 2.5–1.25 mg mL?1, respectively). Exopolysaccharides (EPS) of Gloeocapsa sp. were the sample that exhibited activity against all test pathogens with lowest MIC values (0.125–1 mg mL?1). High activity with a narrower range of susceptible targets demonstrated the exopolysaccharides of Synechocystis sp. and Rhodella reticulata. Antimicrobial activity was proven for phycobiliproteins isolated from Synechocystis sp., Arthrospira fusiformis, Porphyridium aerugineum and Porphyridium cruentum, respectively. In conclusion Gloeocapsa sp. and Synechocystis sp. and especially their exopolysaccharides showed the most promising potential against the examined food pathogens. 相似文献
50.
Leandro da Conceição Laurent Dessemond Elisabeth Djurado Mariana M.V.M. Souza 《International Journal of Hydrogen Energy》2013
La0.7Sr0.3MnO3−δ (LSM) porous films were deposited on different ferritic stainless steels (SS) (430: Cr-16.0%; 439: Cr-16.6%; 444: Cr-17.4%) by sol–gel/dip-coating process. The structure, morphology and composition profiles of investigated assemblies were examined using X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. The area specific resistance (ASR) was measured during long term oxidation in air at 800 °C for 200 h by DC measurements. ASR values lower than 10 mΩ cm2 were recorded after 200 h for LSM-coated SS439 and SS444. This is likely to be due to the high Cr content and to Nb, Ti and Mo elements used to stabilize the stainless steel against oxidation. This paper shows that LSM coatings provide an enhanced stability of the alloy at high temperature and the formation of an interfacial Cr–Mn spinel layer hinders the oxide scale growth. 相似文献