Validation of a food frequency questionnaire for children and adolescents aged 4 to 11 years living in Salvador, Bahia.

OBJECTIVE: To assess the validity of a food frequency questionnaire (FFQ) by applying it to children and adolescents living in Salvador, Bahia. METHODS: The validity of this FFQ with 98 food items was investigated among 108 children and adolescents who were selected from a sample of 1445 that had been planned for a study on the risk factors for asthma and other allergic diseases. The adults responsible for these children and adolescents gave responses for a 24-hour recall (R24h) and an FFQ. The average energy and nutrient values from the FFQ were compared with those from the R24h by means of the paired t test and Pearson correlation coefficients. The concordance was evaluated using the Bland-Altman method and kappa statistics. RESULTS: The energy and nutrient intake estimated using the FFQ was significantly higher than what was obtained using the R24h. The correlation coefficients adjusted for energy were statistically significant for protein, fat, vitamin C and zinc. The weighted kappa values ranged from 0.06 for vitamin A (p = 0.24) to 0.34 for energy (p < 0.00). The results from the Bland-Altman plots for lipid, protein and zinc showed the most significant validity parameters, and zinc was found to show the best concordance. CONCLUSION: The results suggest that the FFQ showed satisfactory validity for use in studies involving children and adolescents

A simple ZVI-Fenton pre-oxidation using steel-nails for NOM degradation in water treatment

The feasibility of a heterogeneous Fenton Process (ZVI/H2O2) using commercial low-carbon-steel nails as the Zero-Valent Iron (ZVI) source was evaluated for the first time for the removal of natural organic matter (NOM) from natural surface waters with distinct physico-chemical characteristics. The synergistic effect of ZVI nails and H2O2 on the process was confirmed. Results showed similar removal efficiencies of NOM in water samples from Thames river and Regent's Park lake (both in London, UK) (under initial pH 3.5 and 100% excess of H2O2 dosage), reaching dissolved organic carbon (DOC) removals of 61.6% ± 3.0 and 59.6% ± 4.7, and UV254 removals of 79.9% ± 0.6 and 77.3 ± 6.2, respectively with 60 min of batch reaction time. ZVI nail surface characterization by scanning electron microscopy (SEM), X-ray energy-dispersive spectroscopy (EDS), and X-ray photoemission spectroscopy (XPS) revealed the formation of a passivating oxide-hydroxide layer on the nail during the reaction, which reduces its surface activity with 20% in continuous use. Results indicate that ZVI/H2O2 process using commercial iron nails is a promising pre-oxidation step for drinking water treatment. The low cost of commercial nails together with the facility of separating them from the water are the main advantages for the application of this process in remote regions with limitations in infrastructure and/or finance

Impacts of behavioural factors on the household water consumption in urban areas

Gaps in understanding what influences household water consumption has led water providers failing to convince their customers to report sustainable practices. To this end, the present study aimed to answer the question, “How do social and cultural factors influence water consumption in urban areas”? The response to this issue has been identified through an investigation that involved a group of selected socio-cultural factors, whose analysis was based on collected survey data from participants in Lagos-Nigeria, Salvador-Brazil, Sao Paulo-Brazil, London-UK and Los Angeles-USA. The Capability-Opportunity-Motivation-Behaviour (COM-B) model was used as a data analysis framework to identify influences. The investigation revealed that Motivation is the most reported driver of water consumption. In a scale from 0 (lowest) to 5 (highest), this component presented the most significant scores in Lagos (3.93), Salvador (4.13), Sao Paulo (3.88), London (4.13) and Los Angeles (3.59). The Capability dimension had the second-highest weight in Lagos, Salvador, Sao Paulo, and Los Angeles, with scores of 2.80, 3.60, 3.60 and 3.20, respectively. Participants from London have Opportunity (score= 2.88) as the second influential pillar in water consumption. These findings are aimed at helping to best drive water saving practices by gaining insight into factors underpinning water consumption in a structured manner

Fenton pre-oxidation of natural organic matter in drinking water treatment through the application of iron nails

This study investigated for the first time the efficiency of an advanced oxidation process (AOP) zero valent iron/hydrogen peroxide (ZVI/H2O2) employing iron nails for the removal of Natural Organic Matter (NOM) from natural water of Regent's Park lake, London, UK. The low cost of nails and their easy separation from the water after the treatment make this AOP attractive for water utilities in low- and middle-income countries. The process was investigated as a pre-oxidation step for drinking water treatment. Results showed that UV254 removal in the natural water was lower than that of simulated water containing commercial humic acid (HA), indicating a matrix effect. Statistical analysis confirmed the maximum removal of dissolved organic carbon (DOC) in natural water depends on the initial pH (best at 4.5) and H2O2 dosage (best at 100% excess of stoichiometric dosage). DOC and UV254 removals under this operational condition were 51% and 89%, respectively. Molecular weight (MW) and specific UV absorbance (SUVA254) were significantly reduced to 74% and 78%, respectively. Formation of chloroform THM in natural water sample after the ZVI/H2O2 process (initial pH 4.5) was below the limit for drinking water, and 48% less than the THM formation in the same water not subjected to pre-oxidation. Characterization of oxidation products on the iron-nail-ZVI surface after the ZVI/H2O2 treatment by SEM, XRD, and XPS identified the formation of magnetite and lepidocrocite. Results suggest that the investigated ZVI/H2O2 process to be a promising technology for removing NOM and reducing THM formation during drinking water treatment

Hematological Changes in Dogs with Visceral Leishmaniasis Are Associated with Increased IFN-γ and TNF Gene Expression Levels in the Bone Marrow

Visceral leishmaniasis is associated with a variety of hematological abnormalities. In this study, we correlated the hematological changes in the peripheral blood of dogs naturally infected with Leishmania infantum (L. infantum) with the distribution of cell lineages and cytokine gene expression patterns in the bone marrow. Samples from 63 naturally semidomiciled dogs living in an endemic area of visceral leishmaniasis were analyzed. L. infantum infection was detected in 50 dogs (79.3%). Among those, 18 (32%) had positive splenic cultures and showed more clinical signs. They also had lower red blood cell counts and leukocytosis with an increased number of neutrophils and monocytes in peripheral blood compared to dogs negative to this test. L. infantum DNA was detected in the bone marrow of 8/14 dogs with positive splenic culture. Dogs with L. infantum infection in the bone marrow presented with histiocytosis (p = 0.0046), fewer erythroid cell clusters (p = 0.0127) and increased gene expression levels of IFN-γ (p = 0.0015) and TNF (p = 0.0091). The data shown herein suggest that inflammatory and cytokine gene expression changes in bone marrow may contribute to the peripheral blood hematological changes observed in visceral leishmaniasis.V.A. was supported by a scholarship from CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), FIOCRUZ and Instituto de Salud Carlos III (ISC-III).S

Modeling the architecture of the regulatory system controlling methylenomycin production in Streptomyces coelicolor

The antibiotic methylenomycin A is produced naturally by Streptomyces coelicolor A3(2), a model organism for streptomycetes. This compound is of particular interest to synthetic biologists because all of the associated biosynthetic, regulatory and resistance genes are located on a single cluster on the SCP1 plasmid, making the entire module easily transferable between different bacterial strains. Understanding further the regulation and biosynthesis of the methylenomycin producing gene cluster could assist in the identification of motifs that can be exploited in synthetic regulatory systems for the rational engineering of novel natural products and antibiotics

Numerical Design and Laboratory Testing of Encapsulated PCM Panels for PCM-Air Heat Exchangers

© 2021 by the authors. Heat transfer between encapsulated PCM panels and air plays an important role in PCM-Air heat exchangers. A new design for the encapsulation panel was developed considering practical aspects such as the cost of production and ease of manufacturing, in addition to heat transfer and pressure drop. A number of encapsulated panel surfaces were first investigated via 3D CFD simulations and compared with an existing panel in use by a commercial PCM-Air heat exchanger manufacturer. After validation, 2D CFD simulations were carried out for 32 different geometries to select the most effective design, which was fabricated and tested in the laboratory. Laboratory parameters tested included heat transfer, pressure drop and melting/solidifying. The laboratory results confirmed the improvements of the new panel in comparison with the existing panel and a flat panel. It was found that the proposed design doubled the heat transfer, holds 13.7% more material and the fan can overcome the increased pressure drop.Thiago Santos would like to thank the Science without Borders program of CNPq-Brazil, for the funding awarded to carry out his PhD at Brunel University London (PDE: 200815/2014-8)

The use of biomimetic surfaces to reduce single- and dual-species biofilms of Escherichia coli and Pseudomonas putida

The ability of bacteria to adhere to and form biofilms on food contact surfaces poses serious challenges, as these may lead to the cross-contamination of food products. Biomimetic topographic surface modifications have been explored to enhance the antifouling performance of materials. In this study, the topography of two plant leaves, Brassica oleracea var. botrytis (cauliflower, CF) and Brassica oleracea capitate (white cabbage, WC), was replicated through wax moulding, and their antibiofilm potential was tested against single- and dual-species biofilms of Escherichia coli and Pseudomonas putida. Biomimetic surfaces exhibited higher roughness values (SaWC = 4.0 ± 1.0 μm and SaCF = 3.3 ± 1.0 μm) than the flat control (SaF = 0.6 ± 0.2 μm), whilst the CF surface demonstrated a lower interfacial free energy (ΔGiwi) than the WC surface (−100.08 mJ m−2 and −71.98 mJ m−2, respectively). The CF and WC surfaces had similar antibiofilm effects against single-species biofilms, achieving cell reductions of approximately 50% and 60% for E. coli and P. putida, respectively, compared to the control. Additionally, the biomimetic surfaces led to reductions of up to 60% in biovolume, 45% in thickness, and 60% in the surface coverage of single-species biofilms. For dual-species biofilms, only the E. coli strain growing on the WC surface exhibited a significant decrease in the cell count. However, confocal microscopy analysis revealed a 60% reduction in the total biovolume and surface coverage of mixed biofilms developed on both biomimetic surfaces. Furthermore, dual-species biofilms were mainly composed of P. putida, which reduced E. coli growth. Altogether, these results demonstrate that the surface properties of CF and WC biomimetic surfaces have the potential for reducing biofilm formation