Feasibility of Using New Sustainable Mineral Additions for the Manufacture of Eco-Cements.

Due to a continuously developing population, our consumption of one of the most widely used building materials, concrete, has increased. The production of concrete involves the use of cement whose production is one of the main sources of CO2 emissions; therefore, a challenge for today's society is to move towards a circular economy and develop building materials with a reduced environmental footprint. This study evaluates the possibility of using new sustainable supplementary cementitious materials (SCMs) from waste such as recycled concrete aggregates (RCAs) and mixed recycled aggregates (MRAs) from construction and demolition waste, as well as bottom ash from olive biomass (BBA-OL) and eucalyptus biomass ash (BBA-EU) derived from the production of electricity. A micronisation pre-treatment was carried out by mechanical methods to achieve a suitable fineness and increase the SCMs' specific surface area. Subsequently, an advanced characterisation of the new SCMs was carried out, and the acquired properties of the new cements manufactured with 25% cement substitution in the new SCMs were analysed in terms of pozzolanicity, mechanical behaviour, expansion and setting time tests. The results obtained demonstrate the feasibility of using these materials, which present a composition with potentially reactive hydraulic or pozzolanic elements, as well as the physical properties (fineness and grain size) that are ideal for SCMs. This implies the development of new eco-cements with suitable properties for possible use in the construction industry while reducing CO2 emissions and the industry's carbon footprint.

Consensus on complementary feeding from the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition: COCO 2023.

Complementary feeding (CF) is defined as the feeding of infants that complements breastfeeding, or alternatively, feeding with a breast milk substitute, and is a process that is more than simply a guide as to what and how to introduce foods. The information provided by healthcare professionals must be up-to-date and evidence-based. Most of the recommendations that appear in the different international guidelines and position papers are widely applicable, but some must be regionalized or adapted to fit the conditions and reality of each geographic zone. The Nutrition Working Group of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) summoned a group of experts from each of the society's member countries, to develop a consensus on CF, incorporating, whenever possible, local information adapted to the reality of the region. The aim of the present document is to show the results of that endeavor. Utilizing the Delphi method, a total of 34 statements on relevant aspects of CF were evaluated, discussed, and voted upon.

In vivo antimicrobial activity of silver nanoparticles produced via a green chemistry synthesis using Acacia rigidula as a reducing and capping agent.

INTRODUCTION: One of the main issues in the medical field and clinical practice is the development of novel and effective treatments against infections caused by antibiotic-resistant bacteria. One avenue that has been approached to develop effective antimicrobials is the use of silver nanoparticles (Ag-NPs), since they have been found to exhibit an efficient and wide spectrum of antimicrobial properties. Among the main drawbacks of using Ag-NPs are their potential cytotoxicity against eukaryotic cells and the latent environmental toxicity of their synthesis methods. Therefore, diverse green synthesis methods, which involve the use of environmentally friendly plant extracts as reductive and capping agents, have become attractive to synthesize Ag-NPs that exhibit antimicrobial effects against resistant bacteria at concentrations below toxicity thresholds for eukaryotic cells. PURPOSE: In this study, we report a green one-pot synthesis method that uses Acacia rigidula extract as a reducing and capping agent, to produce Ag-NPs with applications as therapeutic agents to treat infections in vivo. MATERIALS AND METHODS: The Ag-NPs were characterized using transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction, energy-dispersive spectroscopy, ultraviolet-visible, and Fourier transform infrared. RESULTS: We show that Ag-NPs are spherical with a narrow size distribution. The Ag-NPs show antimicrobial activities in vitro against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and a clinical multidrug-resistant strain of P. aeruginosa) and Gram-positive (Bacillus subtilis) bacteria. Moreover, antimicrobial effects of the Ag-NPs, against a resistant P. aeruginosa clinical strain, were tested in a murine skin infection model. The results demonstrate that the Ag-NPs reported in this work are capable of eradicating pathogenic resistant bacteria in an infection in vivo. In addition, skin, liver, and kidney damage profiles were monitored in the murine infection model, and the results demonstrate that Ag-NPs can be used safely as therapeutic agents in animal models. CONCLUSION: Together, these results suggest the potential use of Ag-NPs, synthesized by green chemistry methods, as therapeutic agents against infections caused by resistant and nonresistant strains.

[Fatty acid concentration analysis in colostrum and transitional milk]. / Análisis de la concentración de ácidos grasos en calostro y leche de transición.

OBJECTIVES: We have studied the quantitative differences in the percent fatty acid composition of human milk throughout its maturational process. MATERIAL AND METHODS: We analyzed milk, obtained by an electrical milk extractor (EGNELL LACT-E AMEDA), from 24 women at 3 days (colostrum) and 7 (transitional milk) after delivery. A Varian 3300 chromatograph was used for fatty acid evaluation. At 48 hours after delivery, the lipid status of the maternal blood was also evaluated. RESULTS: The mean age of the mothers was 27.4 +/- 3.7 years, with 54% primiparous and the mean weight of the newborns was 3117.5 +/- 678.6 g. Comparing colostrum with transitional milk showed a statistically significant difference between saturated fatty acids (C8, C13, and C15) and polyunsaturated fats (C18:3 and C20:4). The concentration of C13, C15, C17, C18, C16:1 and C18:1 obtained in colostrum correlated with those in transitional milk. Serum maternal lipid concentrations of cholesterol and LDL influenced milk levels of C18:2, C18:3 and C20:4. On the contrary, we could not demonstrate a similar influence on triglycerides, apoprotein A or B.