4,852 research outputs found

    Progress in manufacture and properties of construction materials incorporating water treatment sludge: A review

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    © 2019 Elsevier B.V. Water treatment sludge (WTS) management is a growing global problem for water treatment plants (WTPs) and governments. Considering the scarcity of raw materials in many parts of the planet and unique properties of WTS, extensive research has been conducted on the application of WTS in the production of construction materials such as roof tiles, bricks, lightweight aggregates, cement, concrete and geopolymers. This paper critically reviews the progress in the application of WTS in construction materials, by synthesizing results from recent studies. Research findings have revealed that incorporation of ≤10% alum-based sludge in ceramic bricks is satisfactory with a small reduction of mechanical performance. Using the iron-based sludge, the bricks presented better mechanical strength than the reference clay-bricks. Concerning WTS application in concrete, 5% replacement of cement or sand by WTS was considered as the ideal value for the application in a variety of structural and non-structural concrete without adverse effect on concrete mechanical performance. Furthermore, this paper discusses sludge-amended concrete in terms of durability, potential leaching of toxic elements and cost, and suggests topics for future research on the sustainable management of WTS

    Effects of genotype and environment on B-glucan and dietary fibre contents in whole grain of barley grown in Brazil

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    The aim of this study was to determine general quality characteristics of whole grain of advanced lines of barley grown in Brazil and to determine the effects of genotype and growing location on β-glucan and dietary fibre contents. Barley cultivars, designated BRS 225, BRS 195 and MN 743, crop year 2008 and 2009, with three replications in field trial coordinated by the EMBRAPA Trigo/Passo Fundo were used in this research. The barley samples were analyzed in relation to their Total Dietary Fibre (TDF) contents and fractions for moisture and protein (N × 6.25) by using AACC Methods (American Association of Cereal Chemists, 1990). The β-Glucan content was assessed using the McCleary Enzymic Method for barley (McCleary and Codd, 1991). The data was statistically evaluated by System for Analysis and Separation Averages in Agricultural Experiment (SASM-Agri - version 4) and differences between means were located using Scott-Knott’s test (p<0,05). There were significant differences among the barley genotypes and different locations and crop years in terms of β-glucan, total dietary fibre (TDF), soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) content (p<0.05). Climatic factors can affect positively or negatively the content of total dietary fibre and β-glucan, impacting on the final quality of the barley grain. Substantial variation in the content of fibre components was observed for barley cultivars grown in different years on the same location. These results indicate that environmental and genetic factors are involved in the total β-glucan content and dietary fibre of barley

    The European Academy laparoscopic “Suturing Training and Testing’’ (SUTT) significantly improves surgeons’ performance

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    The efficiency of suturing training and testing (SUTT) model by laparoscopy was evaluated, measuring the suturing skill acquisition of trainee gynecologists at the beginning and at the end of a teaching course. During a workshop organized by the European Academy of Gynecological Surgery (EAGS), 25 participants with three different experience levels in laparoscopy (minor, intermediate and major) performed the 4 exercises of the SUTT model (Ex 1: both hands stitching and continuous suturing, Ex 2: right hand stitching and intracorporeal knotting, Ex 3: left hand stitching and intracorporeal knotting, Ex 4: dominant hand stitching, tissue approximation and intracorporeal knotting). The time needed to perform the exercises is recorded for each trainee and group and statistical analysis used to note the differences. Overall, all trainees achieved significant improvement in suturing time (p < 0.005) as measured before and after completion of the training. Similar significantly improved suturing time differences (p < 0.005) were noted among the groups of trainees with different laparoscopic experience. In conclusion a short well-guided training course, using the SUTT model, improves significantly surgeon’s laparoscopic suturing ability, independently of the level of experience in laparoscopic surgery

    Occurrence of deformed wing virus variants in the stingless Melipona subnitida and honey Apis mellifera bee populations in North Eastern Brazil

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    Deformed wing virus (DWV) is now a global insect pathogen. Brazilian stingless bees are a diverse group often managed in close proximity to honey bees. We investigated the prevalence and load of DWV in 33 stingless bees (Melipona subnitida) and 12 honey bees (Apis mellifera) colonies from NE Brazil. DWV was detected in all colonies with the A and C-variants dominating M. subnitida and A-variant in A. mellifera. Viral loads were 8.83E+07 and 7.19E+07 in M. subnitida and A. mellifera, respectively. On Fernando de Noronha island DWV is low (&lt;1E+03) in honey bees, but we detected high loads (1.6E+08) in nine island M. subnitida colonies, indicating no viral spill-over of DWV has occurred during the past 34 years. Furthermore, the ubiquitous presence of the DWV-C variant in M. subnitida colonies, and rarity in A. mellifera, may suggest limited viral exchange between these two species

    Follicular Fluid redox involvement for ovarian follicle growth

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    As the human ovarian follicle enlarges in the course of a regular cycle or following controlled ovarian stimulation, the changes in its structure reveal the oocyte environment composed of cumulus oophorus cells and the follicular fluid (FF).In contrast to the dynamic nature of cells, the fluid compartment appears as a reservoir rich in biomolecules. In some aspects, it is similar to the plasma, but it also exhibits differences that likely relate to its specific localization around the oocyte. The chemical composition indicates that the follicular fluid is able to detect and buffer excessive amounts of reactive oxygen species, employing a variety of antioxidants, some of them components of the intracellular milieu.An important part is played by albumin through specific cysteine residues. But the fluid contains other molecules whose cysteine residues may be involved in sensing and buffering the local oxidative conditions. How these molecules are recruited and regulated to intervene such process is unknown but it is a critical issue in reproduction.In fact, important proteins in the FF, that regulate follicle growth and oocyte quality, exhibit cysteine residues at specific points, whose untoward oxidation would result in functional loss. Therefore, preservation of controlled oxidative conditions in the FF is a requirement for the fine-tuned oocyte maturation process. In contrast, its disturbance enhances the susceptibility to the establishment of reproductive disorders that would require the intervention of reproductive medicine technology.info:eu-repo/semantics/publishedVersio

    Antibacterial, antioxidant and anti-proliferative properties and zinc content of five south Portugal herbs

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    Context: Crataegus monogyna L. (Rosaceae) (CM), Equisetum telmateia L. (Equisataceae) (ET), Geranium purpureum Vil. (Geraniaceae) (GP), Mentha suaveolens Ehrh. (Lamiaceae) (MS), and Lavandula stoechas L. spp. luisieri (Lamiaceae) (LS) are all medicinal. Objective: To evaluate the antioxidant, antiproliferative and antimicrobial activities of plant extracts and quantify individual phenolics and zinc. Material and methods: Aerial part extracts were prepared with water (W), ethanol (E) and an 80% mixture (80EW). Antioxidant activity was measured with TAA, FRAP and RP methods. Phenolics were quantified with a HPLC. Zinc was quantified using voltammetry. Antibacterial activity (after 48 h) was tested using Enterococcus faecalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Listeria monocytogenes. Antiproliferative activity (after 24 h) was tested using HEP G2 cells and fibroblasts. Results: Solvents influenced results; the best were E and 80EW. GP had the highest antioxidant activity (TAA and FRAP of 536.90mg AAE/g dw and 783.48mg TE/g dw, respectively). CM had the highest zinc concentration (37.21 mg/kg) and phenolic variety, with neochlorogenic acid as the most abundant (92.91 mg/100 g dw). LS was rich in rosmarinic acid (301.71 mg/100 g dw). GP and LS inhibited the most microorganisms: B. cereus, E. coli and S. aureus. GP also inhibited E. faecalis. CM had the lowest MIC: 5830 mu g/mL. The antibacterial activity is explained by the phenolics present. LS and CM showed the most significant anti-proliferative activity, which is explained by their zinc content. Conclusion: The most promising plants for further studies are CM, LS and GP.FCT, Fundacao para a Ciencia e a Tecnologia of Portugal [SFRH/BSA/139/2014

    Impact of Lipodystrophy on the prevalence and components of metabolic syndrome in HIV-infected patients

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    Background: In HIV-infected patients, combination antiretroviral therapy (cART) is associated with clinical lipodystrophy (CL) and metabolic abnormalities (MA). This study aimed to evaluate the prevalence of the metabolic syndrome (MS) and its components, and to determine whether patients with or without CL had a different prevalence of MA.Methods: We evaluated 345 HIV-infected patients on cART using two different MS definitions (NCEP-ATPIII-2005 and IDF-2005) and the Framingham risk score.Results: CL was present in 58.7% of the patients. The prevalence of the MS was 52.2% (ATPIII) and 43.2% (IDF), and it was not significantly different between patients with (W) or without (WT) CL, regardless of the definition used (ATPIII WCL 52.9% vs WT CL 51.1%; p = 0.738; IDF WCL 41.3% vs WTCL 46.0%; p = 0.379). Moderate concordance was observed between the 2 definitions (kappa = 0.484; p < 0.001) and after gender stratification there was good concordance in women (kappa = 0.759; p < 0.001). Patients with CL had lower waist circumference and HDL-C and higher triglycerides levels. In women, CL was significantly associated with MS, hypertriglyceridemia and low HDL cholesterol independently of age, cART and BMI. Patients with CL had a significantly higher risk of coronary heart disease at 10 years, measured by the Framingham risk score, than patients without CL. Those with CL and with MS had higher frequencies of moderate and high risk categories than those without MS.Conclusions: The prevalence of the MS was high in these HIV-infected patients with an age average of 40 years and this finding could explain why HIV patients have an increased risk for cardiovascular disease (CVD). © 2011 Freitas et al; licensee BioMed Central Ltd
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