2,822 research outputs found

    Freeze-thaw durability of recycled concrete from construction and demolition wastes

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    Road engineering is one of the most accepted applications for concrete including recycled aggregates from construction and demolition wastes as a partial replacement of the natural coarse aggregates. Amongst the durability concerns of such application, the deterioration due to freeze-thaw cycles is one of the most important causes decreasing the life span of concrete in countries with a continental climate. Moreover, the use of de-icing salts, which is a common practice to prevent ice formation on roadways and walkways, increases the superficial degradation of concrete due to frost-salt scaling. Thus, this paper aims to assess the resistance to frost salt with de-icing salts of two recycled concrete mixtures containing a 50% replacement of the conventional gravel by recycled aggregates both of mixed and ceramic nature, i.e. containing ceramic percentages of 34% and 100%, in comparison to a conventional concrete made with siliceous gravel. Therefore, the surface scaling was evaluated based on EN 1339 (2004) on 28 days cured cylinders, exposed to 7, 14, 21 and 28 freeze-thaw cycles in the presence of sodium chloride solution. Given that no airentraining admixture was used in any of the mixtures, the scaling of both conventional and recycled concretes exceeded the 1 kg/m2 limit established by the European standard. Nonetheless, for the casting surface, the recycled concrete with low ceramic content exhibited a similar behaviour to the conventional concrete, whereas the performance of the recycled concrete with high ceramic content was better. However, as expected, trowelled surfaces showed a worse performance and both recycled concretes had a lower freeze-thaw durability than the conventional mixture. In any case, the results suggested that the composition of the recycled aggregates could be used as a factor to limit the differences in performance between recycled and conventional mixtures

    Detecting web requirements conflicts and inconsistencies under a model-based perspective

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    Web requirements engineering is an essential phase in the software project life cycle for the project results. This phase covers different activities and tasks that in many situations, depending on the analyst’s experience or intuition, help getting accurate specifications. One of these tasks is the conciliation of requirements in projects with different groups of users. This article presents an approach for the systematic conciliation of requirements in big projects dealing with a model-based approach. The article presents a possible implementation of the approach in the context of the NDT (Navigational Development Techniques) Methodology and shows the empirical evaluation in a real project by analysing the improvements obtained with our approach. The paper presents interesting results that demonstrate that we can get a reduction in the time required to find conflicts between requirements, which implies a reduction in the global development costs.Laboratorio de Investigación y Formación en Informática Avanzad

    Detecting web requirements conflicts and inconsistencies under a model-based perspective

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    Web requirements engineering is an essential phase in the software project life cycle for the project results. This phase covers different activities and tasks that in many situations, depending on the analyst’s experience or intuition, help getting accurate specifications. One of these tasks is the conciliation of requirements in projects with different groups of users. This article presents an approach for the systematic conciliation of requirements in big projects dealing with a model-based approach. The article presents a possible implementation of the approach in the context of the NDT (Navigational Development Techniques) Methodology and shows the empirical evaluation in a real project by analysing the improvements obtained with our approach. The paper presents interesting results that demonstrate that we can get a reduction in the time required to find conflicts between requirements, which implies a reduction in the global development costs.Laboratorio de Investigación y Formación en Informática Avanzad

    Numerical semigroups with a given set of pseudo-Frobenius numbers

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    The pseudo-Frobenius numbers of a numerical semigroup are those gaps of the numerical semigroup that are maximal for the partial order induced by the semigroup. We present a procedure to detect if a given set of integers is the set of pseudo-Frobenius numbers of a numerical semigroup and, if so, to compute the set of all numerical semigroups having this set as set of pseudo-Frobenius numbers

    Quality improvement of mixed and ceramic recycled aggregates by biodeposition of calcium carbonate

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    This research focuses on improving the quality of mixed and ceramic recycled aggregates by microbially induced carbonate precipitation (Bacillus sphaericus). The precipitation contributed to a weight increase and unleashed a waterproofing response. The roughness of the ceramic particles created a more uniform layer compared to natural or concrete particles. For the concrete fraction, which had a higher macroporosity, the consolidation effect was more pronounced. High ceramic content aggregates profited from a greater biodeposition, leading to a remaining amount of precipitates after sonication which was still greater than in cementitious materials. Pore-filling effect was detected by SEM, supporting the waterproofing result. (C) 2017 Elsevier Ltd. All rights reserved

    Local detection of microvessels in IDH-wildtype glioblastoma using relative cerebral blood volume: an imaging marker useful for astrocytoma grade 4 classification

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    [EN] Background The microvessels area (MVA), derived from microvascular proliferation, is a biomarker useful for high-grade glioma classification. Nevertheless, its measurement is costly, labor-intense, and invasive. Finding radiologic correlations with MVA could provide a complementary non-invasive approach without an extra cost and labor intensity and from the first stage. This study aims to correlate imaging markers, such as relative cerebral blood volume (rCBV), and local MVA in IDH-wildtype glioblastoma, and to propose this imaging marker as useful for astrocytoma grade 4 classification. Methods Data from 73 tissue blocks belonging to 17 IDH-wildtype glioblastomas and 7 blocks from 2 IDH-mutant astrocytomas were compiled from the Ivy GAP database. MRI processing and rCBV quantification were carried out using ONCOhabitats methodology. Histologic and MRI co-registration was done manually with experts' supervision, achieving an accuracy of 88.8% of overlay. Spearman's correlation was used to analyze the association between rCBV and microvessel area. Mann-Whitney test was used to study differences of rCBV between blocks with presence or absence of microvessels in IDH-wildtype glioblastoma, as well as to find differences with IDH-mutant astrocytoma samples. Results Significant positive correlations were found between rCBV and microvessel area in the IDH-wildtype blocks (p < 0.001), as well as significant differences in rCBV were found between blocks with microvascular proliferation and blocks without it (p < 0.0001). In addition, significant differences in rCBV were found between IDH-wildtype glioblastoma and IDH-mutant astrocytoma samples, being 2-2.5 times higher rCBV values in IDH-wildtype glioblastoma samples. Conclusions The proposed rCBV marker, calculated from diagnostic MRIs, can detect in IDH-wildtype glioblastoma those regions with microvessels from those without it, and it is significantly correlated with local microvessels area. In addition, the proposed rCBV marker can differentiate the IDH mutation status, providing a complementary non-invasive method for high-grade glioma classification.This work was funded by grants from the National Plan for Scientific and Technical Research and Innovation 2017-2020, No. PID2019-104978RB-I00) (JMGG); H2020-SC1-2016-CNECT Project (No. 727560) (JMGG), and H2020SC1-BHC-2018-2020 (No. 825750) (JMGG). M.A.T was supported by DPI201680054-R (Programa Estatal de Promocion del Talento y su Empleabilidad en I + D + i). EFG was supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 844646. The funding body played no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript.Álvarez-Torres, MDM.; Fuster García, E.; Juan-Albarracín, J.; Reynes, G.; Aparici-Robles, F.; Ferrer Lozano, J.; Garcia-Gomez, JM. (2022). Local detection of microvessels in IDH-wildtype glioblastoma using relative cerebral blood volume: an imaging marker useful for astrocytoma grade 4 classification. BMC Cancer. 22(1):1-13. https://doi.org/10.1186/s12885-021-09117-411322

    Cost-Utility Analysis of a Medication Adherence Management Service Alongside a Cluster Randomized Control Trial in Community Pharmacy.

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    Background: It is necessary to determine the cost utility of adherence interventions in chronic diseases due to humanistic and economic burden of non-adherence. Purpose: To evaluate, alongside a cluster-randomized controlled trial, the cost-utility of a pharmacist-led medication adherence management service (MAMS) compared with usual care in community pharmacies. Materials and Methods: The trial was conducted over six months. Patients with treatments for hypertension, asthma or chronic obstructive pulmonary disease (COPD) were included. Patients in the intervention group (IG) received a MAMS based on a brief complex intervention, whilst patients in the control group (CG) received usual care. The cost–utility analysis adopted a health system perspective. Costs related to medications, healthcare resources and adherence intervention were included. The effectiveness was estimated as quality-adjusted life years (QALYs), using a multiple imputation missing data model. The incremental cost–utility ratio (ICUR) was calculated on the total sample of patients. Results: A total of 1186 patients were enrolled (IG: 633; CG: 553). The total intervention cost was estimated to be € 27.33 ± 0.43 per patient for six months. There was no statistically significant difference in total cost of medications and healthcare resources per patient between IG and CG. The values of EQ-5D-5L at 6 months were significantly higher in the IG [IG: 0.881 ± 0.005 vs CG: 0.833 ± 0.006; p = 0.000]. In the base case, the service was more expensive and more effective than usual care, resulting in an ICUR of € 1,494.82/QALY. In the complete case, the service resulted in an ICUR of € 2,086.30/QALY, positioned between the north-east and south-east quadrants of the cost–utility plane. Using a threshold value of € 20,000/QALY gained, there is a 99% probability that the intervention is cost-effective. Conclusion: The medication adherence management service resulted in an improvement in the quality of life of the population with chronic disease, with similar costs compared to usual care. The service is cost-effective

    Glioblastoma: Vascular Habitats Detected at Preoperative Dynamic Susceptibility-weighted Contrast-enhanced Perfusion MR Imaging Predict Survival

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    [EN] Purpose: To determine if preoperative vascular heterogeneity of glioblastoma is predictive of overall survival of patients undergoing standard-of-care treatment by using an unsupervised multiparametric perfusion-based habitat-discovery algorithm. Materials and Methods: Preoperative magnetic resonance (MR) imaging including dynamic susceptibility-weighted contrast material-enhanced perfusion studies in 50 consecutive patients with glioblastoma were retrieved. Perfusion parameters of glioblastoma were analyzed and used to automatically draw four reproducible habitats that describe the tumor vascular heterogeneity: high-angiogenic and low-angiogenic regions of the enhancing tumor, potentially tumor-infiltrated peripheral edema, and vasogenic edema. Kaplan-Meier and Cox proportional hazard analyses were conducted to assess the prognostic potential of the hemodynamic tissue signature to predict patient survival. Results: Cox regression analysis yielded a significant correlation between patients' survival and maximum relative cerebral blood volume (rCBV(max)) and maximum relative cerebral blood flow (rCBF(max)) in high-angiogenic and low-angiogenic habitats (P < .01, false discovery rate-corrected P < .05). Moreover, rCBF(max) in the potentially tumor-infiltrated peripheral edema habitat was also significantly correlated (P < .05, false discovery rate-corrected P < .05). Kaplan-Meier analysis demonstrated significant differences between the observed survival of populations divided according to the median of the rCBV(max) or rCBF(max) at the high-angiogenic and low-angiogenic habitats (log-rank test P < .05, false discovery rate-corrected P < .05), with an average survival increase of 230 days. Conclusion: Preoperative perfusion heterogeneity contains relevant information about overall survival in patients who undergo standard-of-care treatment. The hemodynamic tissue signature method automatically describes this heterogeneity, providing a set of vascular habitats with high prognostic capabilities.Study supported by H2020 European Institute of Innovation and Technology (POC-2016.SPAIN-07) and Universitat Politecnica de Valencia (PAID-10-14). J.J.A., E.F.G., and J.M.G.G. supported by Secretaria de Estado de Investigacion, Desarrollo e Innovacion (DPI2016-80054-R, TIN2013-43457-R). E.F.G. supported by CaixaImpulse program from Fundacio Bancaria "la Caixa" (LCF/TR/CI16/10010016). E.F.G and A.A.B. supported by the Universitat Politecnica de Valencia Instituto Investigacion Sanitaria de La Fe (C05).Juan -Albarracín, J.; Fuster García, E.; Pérez-Girbés, A.; Aparici-Robles, F.; Alberich Bayarri, A.; Revert Ventura, AJ.; Martí Bonmatí, L.... (2018). Glioblastoma: Vascular Habitats Detected at Preoperative Dynamic Susceptibility-weighted Contrast-enhanced Perfusion MR Imaging Predict Survival. Radiology. 287(3):944-954. https://doi.org/10.1148/radiol.2017170845S944954287

    Simultaneous Treatment with Statins and Aspirin Reduces the Risk of Prostate Cancer Detection and Tumorigenic Properties in Prostate Cancer Cell Lines

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    Nowadays prostate cancer is the most common solid tumor in men from industrialized countries and the second leading cause of death. At the ages when PCa is usually diagnosed, mortality related to cardiovascular morbidity is high; therefore, men at risk for PCa frequently receive chronic lipid-lowering and antiplatelet treatment. The aim of this study was to analyze how chronic treatment with statins, aspirin, and their combination influenced the risk of PCa detection. The tumorigenic properties of these treatments were evaluated by proliferation, colony formation, invasion, and migration assays using different PCa cell lines, in order to assess how these treatments act at molecular level. The results showed that a combination of statins and aspirin enhances the effect of individual treatments and seems to reduce the risk of PCa detection (OR: 0.616 (95% CI: 0.467-0.812), P < 0.001). However, if treatments are maintained, aspirin (OR: 1.835 (95% CI: 1.068-3.155), P = 0.028) or the combination of both drugs (OR: 3.059 (95% CI: 1.894-4.939), P < 0.001) represents an increased risk of HGPCa. As observed at clinical level, these beneficial effects in vitro are enhanced when both treatments are administered simultaneously, suggesting that chronic, concomitant treatment with statins and aspirin has a protective effect on PCa incidence
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