Factors determining the breastfeeding in children attending public and not-for-profit daycare centers in São Paulo, Brazil

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.     

Value Stream Mapping: a study about the problems and challenges found in the literature from the past 15 years about application of Lean tools

Value stream mapping (VSM) is an important tool of the lean approach and is used to identify value-adding activities and those considered wasteful of materials and the flow of information and people. However, when not applied correctly, VSM can complicate the identification of waste, lead to misinterpretations and assessment mistakes, and undermine the implementation of future improvements. The purpose of this paper is to investigate the main difficulties and limitations encountered during the construction of current state maps, analysis of the associated causes, and pointing out of guidelines to facilitate the use of VSM to map processes. To do so, a search and evaluation of papers in journals, conferences, theses, and dissertations was conducted, and the articles were categorized according to the field of application (factory floor, supply chain, product development and services) and approach (theoretical or practical). In conclusion, this paper criticizes some ways that VSM has been used, observing that important constraints created by its application must be considered and that when used incorrectly, the tool can lead to mistakes that can cause problems instead of benefits. Considering the problems identified, the paper suggests future works for improving the use of VSM for mapping processes.     

Chemiotropic behavior of female olive fly (Bactrocera oleae GMEL.) onOlea europaea L

An interpretation is given of a number of observations on the chemiotropic behavior ofBactrocera oleae in connection with olive maceration water and the fly's return to the olive groves after the first summer rains. To this end, the headspace of both maceration water and leaf leaching water, simulating rainfall, were examined. In both cases, the presence of ammonia, which is generally known to attract fruit flies (Diptera, Tephritidae), was detected and, for the first time, in addition to other compounds that are inert for the fly, the presence of styrene was also detected. This aromatic hydrocarbon was found to be a strong attractant. It is shown that both ammonia and styrene are products of the metabolism of microbial flora present on the olive and leaf surface.     

Poly(vinylidene fluoride) with zinc oxide and carbon nanotubes applied to pressure sheath layers in oil and gas pipelines

In this work, PVDF composites containing 0.2% (m/m) of carbon nanotubes (MWCNTs), PVDF with 5.0% (m/m) of zinc oxide (ZnO), and composites containing both particles in the same contents in the matrix were melt processed in a mini-extruder machine with double screws, using the counter-rotation mode. Composites were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), dynamic-mechanical analysis (DMA), and contact angle tests (CA). The samples presented the predominance of the α phase, with an increased degree of crystallinity as well as an increase in dimensional stability by incorporating both fillers, showing a synergistic effect between these particles, as shown on FTIR, DSC, and XRD results. SEM images showed a good dispersion of high aspect ratio particles. In general, DMA and TGA analysis showed that composites had not decreased their thermal and mechanical performance when compared to neat PVDF. Results of CA analysis showed an increase in the hydrophobicity of the sample containing MWCNTs. Permeability tests were also performed using a differential pressure system, combining high temperature and pressure, obtaining permeability measures and time lag. This work presents an alternative of composite materials, suggesting its application in the internal pressure sheath layers of oil and gas flexible pipes.     

Hydrogen PEMFC stack performance analysis: A data-driven approach

For low power fuel cells, management of reactants, water and heat, must be realized in a passive fashion in order to minimize parasitic losses. Effective fuel, oxygen supply and water management for reliable performance are also greatly affected by cell geometry and materials. These are complex systems to optimize on a mere experimental basis. As an aid to this goal, data-driven analysis techniques, requiring no a priori mathematical model, are gaining a reputation in other research fields, where phenomenological modeling approaches might be intractable.     

Simultaneous analysis of carbohydrates and volatile fatty acids by HPLC for monitoring fermentative biohydrogen production

The production of biohydrogen through anaerobic fermentation has received increasingly attention and has great potential as an alternative process for clean fuel production in the future. The monitoring of the stages of anaerobic fermentation provides relevant information about the bioprocess. The objective of this study is to propose a novel methodology for simultaneous analysis of sucrose, glucose, fructose and volatile fatty acids (VFAs), such as, acetic, propionic, isobutyric and butyric during anaerobic fermentation by using high-performance liquid chromatography (HPLC). The following chromatographic conditions were optimized: column Aminex HPX-87H, mobile phase consisting of H₂SO₄ 0.005 mol/L, flow rate of 1.0 mL/min and temperature of 55 °C. Sucrose, glucose and fructose were analyzed by refractive index detector (RI) while acetic, propionic, isobutyric and butyric acids were analyzed by ultraviolet (UV) detection at 210 nm. Some analytical parameters of validation, such as, linearity, selectivity, repeatability, intermediate precision, limit of detection and quantification, accuracy and robustness were evaluated. The proposed methodology was successfully applied in the determination of substrates and metabolites during different stages of biohydrogen production.     

An assessment of energy benefits of efficient household air-conditioners in Brazil

Increasing efficiency of electrical equipment is essential to national energy rationality, enabling energy consumption reduction and postponing inversion in distribution, transmission and generation, as well as mitigating environmental impacts associated with such activities. Considering such purposes, two actions have been promoted in Brazil: (a) minimum energy performance standards (MEPS) have been required for some appliances and (b) consumers have been informed about the most efficient products by ??endorsement labeling.?? The purpose of this study is to assess window and split air-conditioners with Brazilian MEPS. To evaluate the impact of efficient air-conditioners in this market, a model was developed based on estimates for quantity of equipment in operation and unitary consumption, as determined by local temperature records. From this model, it was deduced that using only efficient conditioners (class A for Brazilian Labeling Program/INMETRO, with PROCEL Label) an annual saving of 322?GWh and a reduction in demand of 109?MW could be obtained in 2007. Furthermore, it was observed that the current MEPS established by Brazilian legislation for air-conditioners may be considered relatively low. Considering that MEPS are similar to those observed in China (the main exporter of air-conditioners to the Brazil), an energy saving of roughly 222?GWh could be achieved in the same year. Impacts on emission of greenhouse gases are also estimated.     

Can regional policies shape migration flows?

Our empirical analysis focuses on the effect of regional policies on migration attraction factors in Europe. We employ a regression discontinuity design to assess the causal relationship between the reception of large amounts of public funds and migration flows in the EU-15 regions. In highly-subsidised regions, we find a large increase in the share of foreign citizens from less-developed countries when compared to low-subsidised regions with similar pre-treatment characteristics. The analysis shows that such an increase is due to the positive impact of the European regional policy on job market opportunities as well as the improvement of public goods supply.     

A theoretical and experimental study of phosphate ester inhibitors for AISI 1018 in carbon dioxide-saturated 3.5 wt% NaCl solution

Phosphate ester was investigated as a corrosion inhibitor for AISI 1018 carbon steel in carbon dioxide-saturated chloride solutions at different temperatures and pressures. The corrosion tests were realized by electrochemical techniques, weight loss measurements, bubble tests, and a high-pressure/high-temperature autoclave system. The corrosion tests demonstrated that the investigated molecule is an excellent corrosion inhibitor. The inhibiting effect is even bigger at high pressure and temperature than at atmospheric pressure and room temperature. The thermodynamic parameters were calculated and determined to obey the Langmuir isotherm. Polarization studies revealed that the evaluated inhibitor is a mixed type.