212 research outputs found

    Rheology, Durability, and Mechanical Performance of Sustainable Self-Compacting Concrete With Metakaolin and Limestone Filler

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    Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] This study analyzed the performance of self-compacting concrete with a paste composition that includes limestone filler and metakaolin replacing cement to design binary (75% cement and 25% limestone filler) and ternary binders (60% cement, 25% limestone filler and 15% metakaolin). Furthermore, to analyze the effect of the solid volume fraction (volume of sand and coarse aggregate) on concrete rheology, the concretes were designed using four volumes of paste (350 l, 400 l, 450 l and 500 l). Rheological tests were performed at three resting times to measure the viscosity and yield stress over time. The results indicated that the viscosity decreased by 43.3% when the cement was replaced by limestone filler and increased by 73.1% when the cement was replaced by 15% metakaolin while maintaining the limestone filler. These values were obtained as 27.6% and 62.2%, respectively, when the yield stress was analyzed. In addition, the hardened properties (mechanical behavior and durability) were studied by measuring the strengths at 28 days, as well as the electrical resistivity and ultrasonic pulse velocity over time. In this case, at 28 days the use of binary binder reduces the strength and resistivity (about 20%) and the employment of ternary binder reduces strength (15%) while increases the resistivity up to the double (when compared to the 100 C concrete). Moreover, to measure the efficiency of the concrete, a material index was designed that considers the fresh behavior, mechanical performance, durability, cost, and environmental impact. Self-compacting concretes with ternary binders provided the highest indices. The use of alternative materials, particularly metakaolin has been proven to be a good option to enhance concrete sustainable performance.The study is part of two projects entitled: “Robust self-compacting recycled concretes: rheology in fresh state and mechanical properties (Ref: BIA2014-58063-R)” and “Sustainable High Performance Self-Compacting Concrete using low clinker cement, and integral curing and self-healing agents (HACCURACEM) (BIA2017-85657-R)” funded by MINECO. Moreover, this work was also made possible by the financial support of a pre-doctoral grant of MINECO (FPI 2015- ref BES-2015-071919) and two grants for international pre-doctoral stays: (a) FPI 2015 and (b) IACOBUS program for “Galicia–North of Portugal Euroregion

    A proposal of a mixed diagnostic system based on decision trees and probabilistic experts rules

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    Decision trees and rule-based expert systems (RBES) are standard diagnostic tools. We propose a mixed technique that starts with a probabilistic decision tree where information is obtained from a real world data base. The decision tree is automatically translated into a set of probabilistic rules. Meanwhile a panel of experts proposes their own set of probabilistic rules, according with their experience on the subject. Both sets of rules are combined, generating a mixed RBES with probabilistic rules. The expected probabilities of the rules translating the knowledge in the decision tree are discretized by considering a mapping from intervals of expected probabilities into a set of five values. This way, knowledge coming from real data is completed with the experience of the panel of experts in order to provide a more accurate prediction of suffering from type 2 diabetes mellitus (T2DM) before seven and a half years in the future. The proposed technique is illustrated with a real case using a diabetes diagnosis probabilistic decision tree built using 1350 out of 1800 real cases and the rules provided by a panel of experts in diabetes. The final result takes into account both the probabilities of the rules and the number of times that each possible consequent is reached, giving a probabilistic result among seven possibilities. For modeling the decision tree, 75% of the individuals in the database (randomly selected) have been used and the rest (25%) have been used to test the results. The results of the Mixed RBES have been compared with the results of the Tree RBES (the RBES built using only the rules from the decision tree) and the results of the Experts’ RBES (the RBES built using only the rules from the panel of experts). The accuracy of the predictions of the Mixed RBES is much better.Funding for open access charge: Universidad de Málaga / CBU

    Comparing and Tuning Machine Learning Algorithms to Predict Type 2 Diabetes Mellitus

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    The main goals of this work is to study and compare machine learning algorithms to predict the development of type 2 diabetes mellitus. Four classifi cation algorithms have been considered, studying and comparing the accuracy of each one to predict the incidence of type 2 diabetes mellitus seven years in advance. Specifically, the techniques studied are: Decision Tree, Random Forest, kNN (k-Nearest Neighbors) and Neural Networks. The study not only involves the comparison among these techniques, but also, the tuning of the meta-parameters in each algorithm. The algorithms have been implemented using the language R. The data base used is obtained from the nation-wide cohort [email protected] study. The conclusions will include the accuracy of each algorithm and therefore the best technique for this problem. The best meta-parameters for each algorithm will be also provided.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Archaeology of the battle of Catalonia (1939). Excavations of a section of the defensive Line L-3 in Subirats (Alt Penedès, Barcelona)

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    En aquest article descrivim els resultats de la intervenció arqueològica realitzada en les restes de les estructures defensives de la Guerra Civil espanyola al poble de Sant Pau d’Ordal, Subirats (Alt Penedès, Barcelona) que van estar operatives en les darreres fases del conflicte a Catalunya (gener de 1939). Tot i l’elevat nombre d’aquestes, cap dels elements excavats proporcionà un nombre significatiu de materials de l’època. Per això, reflexionem també aquí sobre la problemàtica de l’escàs grau de protecció del patrimoni arqueològic de la Guerra Civil.In this paper we report the results of the archaeological intervention carried out on the remains of defensive structures from Spanish Civil War in the village of Sant Pau d’Ordal, Subirats (Alt Penedès, Barcelona) that were operational in the latter stages of the conflict in Catalonia (January 1939). Despite their high number, none of the items excavated provided a significant number of materials from the period. So here also it is reflected on the problem of the low level of protection of the archaeological heritage of the Spanish Civil War

    Trypanosomatid infections among vertebrates of Chile: a systematic review

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    We present a review on the natural infection by trypanosomatids of nonhuman vertebrates in Chile, aiming to synthesize and update the knowledge on the diversity of trypanosomatids infecting native and alien vertebrate species. To this end, we conducted a systematic review of literature records published from 1900 to April 2020 on four databases, focusing on the 21 genera of trypanosomatids and Chile. The methods and findings of our review have been based on the preferred reporting items for systematic reviews and meta-analysis (prisma) checklist. We found 29,756 records but only 71 presented relevant information for this review. Overall, there are only two reported trypanosomatid genera infecting vertebrate species in Chile, the genera Trypanosoma and Leishmania. The former is mostly represented by Trypanosoma cruzi (90% of the total records) and to a much lesser extent by Trypanosoma avium, Trypanosoma humboldti, Trypanosoma lewisi, and a couple of unidentified trypanosomatids. A total of 25 mammals have been reported as being infected by T. cruzi, including 14 native and 11 alien species from Orders Artiodactyla, Carnivora, Chiroptera, Didelphimorphia, Lagomorpha, Perissodactyla, and Rodentia. Extensive screening studies using new analytical tools are necessary to grasp the whole potential diversity of trypanosomatid species infecting vertebrates in Chile

    Influencia de las variaciones en los materiales sobre la reología de hormigones autocompactantes reciclados

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    [ES] Este trabajo se centra en el análisis de la influencia de las variaciones de materiales sobre el comportamiento reológico de los hormigones autocompactantes fabricados con árido grueso reciclado. Se diseña un hormigón autocompactante patrón y tres reciclados con porcentajes de sustitución del 20%, 50% y 100% en volumen. Asimismo, en cada una de estas mezclas se aplican variaciones en el contenido de agua, superplastificante y cemento para simular los errores que se producen en las plantas de fabricación: ± 3% en el agua, ± 5% en el superplastificante y ± 3% en el cemento. Todos los hormigones se estudian en estado fresco mediante los ensayos reológicos stress growth test y flow curve test. Mediante reógrafos se evalúan los cambios reológicos que los incrementos o decrementos de agua, superplastificante o cemento pueden ocasionar. Los resultados permiten estudiar a qué variación de material es más sensible un hormigón autocompactante reciclado (HACR) y qué porcentajes de árido reciclado sería más recomendable utilizar para obtener un hormigón robusto.Este estudio es parte de los proyectos (a) “Investigación industrial sobre Hormigones para un Mercado Sostenible (InHorMeS)” financiado por la Axencia Galega de Innovación (Ref: IN852A 2013/57); y (b) “Hormigones reciclados autocompactantes robustos: reología en estado fresco y propiedades mecánicas (HORREO)” financiado por el Ministerio de Economía y Competitividad (Ref: BIA2014-58063-R). Además, este trabajo fue posible gracias al apoyo de una beca predoctoral de la Xunta de Galicia (España).González Taboada, I.; González Fonteboa, B.; Martinez Abella, F.; Rojo López, G. (2018). Influencia de las variaciones en los materiales sobre la reología de hormigones autocompactantes reciclados. En HAC 2018. V Congreso Iberoamericano de hormigón autocompactable y hormigones especiales. Editorial Universitat Politècnica de València. 65-74. https://doi.org/10.4995/HAC2018.2018.6361OCS657

    Archaeology of the battle of Catalonia (1939). Excavations of a section of the defensive Line L-3 in Subirats (Alt Penedès, Barcelona)

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    En aquest article descrivim els resultats de la intervenció arqueològica realitzada en les restes de les estructures defensives de la Guerra Civil espanyola al poble de Sant Pau d’Ordal, Subirats (Alt Penedès, Barcelona) que van estar operatives en les darreres fases del conflicte a Catalunya (gener de 1939). Tot i l’elevat nombre d’aquestes, cap dels elements excavats proporcionà un nombre significatiu de materials de l’època. Per això, reflexionem també aquí sobre la problemàtica de l’escàs grau de protecció del patrimoni arqueològic de la Guerra Civil.In this paper we report the results of the archaeological intervention carried out on the remains of defensive structures from Spanish Civil War in the village of Sant Pau d’Ordal, Subirats (Alt Penedès, Barcelona) that were operational in the latter stages of the conflict in Catalonia (January 1939). Despite their high number, none of the items excavated provided a significant number of materials from the period. So here also it is reflected on the problem of the low level of protection of the archaeological heritage of the Spanish Civil War

    The nutrigenetic influence of the interaction between dietary vitamin E and TXN and COMT gene polymorphisms on waist circumference: a case control study

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    Journal Article; Research Support, Non-U.S. Gov't;BACKGROUND Abdominal obesity (AO) is a common modifiable risk factor for certain non-communicable diseases associated with enhanced oxidative stress (OS). The objective of this work was to investigate whether the interaction between antioxidant vitamin intake and OS-related polymorphisms modulates gene-associated anthropometry in a Spanish population. METHODS A total of 246 subjects with AO, and 492 age and gender matched non-AO subjects were included in the study. Anthropometric, biochemical, and OS parameters, and antioxidant dietary intake data were assessed using validated procedures. DNA from white blood cells was isolated and the genotype of seven polymorphisms from genes involved in OS (pro-oxidant and antioxidant) were analyzed using the SNPlex system. The effects of the c.-793T > C polymorphism on promoter activity and thus thioredoxin (TXN) activity were examined using reporter assays. RESULTS The AO group had higher 8-Oxo-2'-deoxyguanosine levels and took in less vitamin A and vitamin E compared to the non-AO group. Logistic regression analysis revealed that the rs2301241 polymorphism in TXN and rs740603 in catechol-O-methyltransferase (COMT) were associated with waist circumference (WC) and AO. Moreover, these polymorphisms were more strongly associated with variations in WC in subjects with low vitamin E intakes. A promoter assay revealed that the T to C conversion at c.-793 (rs2301241) induced a more than two fold increase in reporter gene expression. CONCLUSIONS WC is associated both with dietary vitamin E intake and genetic variants of TXN and COMT suggesting that existence of a complex nutrigenetic pathway that involves regulation of AO.This work was co-funded with European Funds for Regional Development (FEDER), the Spanish Science and Technology Ministry [SAF2005-02883]; the health research fund from the Carlos III Health Institute [PI070497], CIBER Fisiopatología Obesidad y Nutrición (CIBERobn) [CB06/03], and CIBER de Diabetes y Enfermedades Metabólicas Relacionadas (CIBERDEM). CIBEROB and CIBERDEM are initiatives by the Carlos III Health Institute in Madrid and the Spanish Health Ministry. Funding also came from GRUPOS 03/101, PROMETEO/2009/029 and 2005/027, AMP07/075, and ACOMP/2009/201 from the Valencian Government and European Network of Excellence InGenious HyperCare (EPSS-037093) from the European Commission.Ye

    Hypertension is related to the degradation of dietary frying oils

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    [Background]: The family kitchen resembles an uncontrolled laboratory experiment, and some discrepancies in the relation between the risk of hypertension and dietary fat may be partly due to the manipulation to which the fats were subjected. [Objective]: We investigated whether deterioration in the quality of the cooking oils in the family household contributes to the risk of high blood pressure. [Design]: The study was cross-sectional. Anthropometric measurements were obtained for 1226 persons aged 18–65 y who were selected randomly from the municipal census of Pizarra, Spain. An oral-glucose-tolerance test was given to 1020 of these persons. Samples of the cooking oil being used were taken from the kitchens of a random subset of 538 persons. The concentrations of polar compounds and polymers were used as markers of the deterioration of the oils. The strength of association between variables was measured by calculating the odds ratio from logistic models. [Results]: Hypertension was strongly associated with obesity and was influenced by sex, diabetes, and age. The presence of excess polar compounds in the cooking oil and the use of sunflower oil were related to the risk of hypertension, whereas the concentration of monounsaturated fatty acids in the serum phospholipids was negatively related to this risk. These associations remained after inclusion in the models of age, sex, obesity, and the presence of carbohydrate metabolism disorder. [Conclusions]: The risk of hypertension is positively and independently associated with the intake of cooking oil polar compounds and inversely related to blood concentrations of monounsaturated fatty acids

    Serum vascular endothelial growth factor b and metabolic syndrome incidence in the population based cohort [email protected] study

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    Background/Objectives Although vascular endothelial growth factor b (VEGFb) might have an impact on the development of obesity, diabetes and related disorders, the possible relationship between VEGFb serum levels and the incidence of these metabolic complications in humans is still unknown. The aim of our study was to evaluate the association between VEGFb serum levels and the new-onset of metabolic syndrome (MS) and its components in the Spanish adult population after 7.5 years of follow-up. Subjects/Methods A total of 908 subjects from the [email protected] cohort study without MS at cross-sectional stage according to International Diabetes Federation (IDF) or Adult Treatment Panel III (ATP-III) criteria were included. Additionally, five sub-populations were grouped according to the absence of each MS component at baseline. Socio-demographic, anthropometric and clinical data were recorded. The Short Form of International Physical Activity Questionnaire (SF-IPAQ) was used to estimate physical activity. A fasting blood extraction and an oral glucose tolerance test were performed. Serum determinations of glucose, lipids, hsCRP and insulin were made. VEGFb levels were determined and categorized according to the 75th percentile of the variable. New cases of MS and its components were defined according to ATPIII and IDF criteria. Results A total of 181 or 146 people developed MS defined by IDF or ATP-III criteria respectively. Serum triglyceride levels, hs-CRP and systolic blood pressure at the baseline study were significantly different according to the VEGFb categories. Adjusted logistic regression analysis showed that the likelihood of developing MS and abdominal obesity was statistically reduced in subjects included in the higher VEGFb category. Conclusion Low serum levels of VEGFb may be considered as early indicators of incident MS and abdominal obesity in the Spanish adult population free of MS, independently of other important predictor variables.This investigation has been supported by CIBERDEM (Ministerio de Economia, Industria y Competitividad-ISCIII), Ministerio de Sanidad, Servicios Sociales e IgualdadISCIII, Instituto de Salud Carlos III (research grants PI20/01322, PI18/01165, PI17/02136, PI14/00710) and cofunding by the European Regional Development Fund (ERDF) "A way to build Europe". LifeScan Espana (Madrid, Spain) kindly donated the glucometers and test strips for capillary glucose measurements. Cristina MaldonadoAraque is a researcher in the `Rio Hortega' program (CM19/00186) financed by the Instituto de Salud Carlos III. Natalia Colomo is a member of the regional "Accion B para clinicos investigadores" research program of the Consejeria de Salud of the Junta de Andalucia, Spain (B-0002-17). Gemma Rojo-Martinez belongs to the Nicolas Monardes research program of the Consejeria de Salud (C-0060-2012; Junta de Andalucia, Spain)
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