Bond between steel reinforcement bars and Electric Arc Furnace slag concrete

This paper deals with the bond between steel reinforcement and recycled aggregate concrete, including Electric arc furnace (EAF) slag as full replacement of natural coarse aggregates. Pull-out tests were carried out according to RILEM standard on specimens made with six concrete mixtures, characterized by different w/c ratios and types of aggregates. Plain and ribbed steel reinforcement bars were used to observe the influence of steel roughness. Experimental bond-slip relationships were analyzed, and results show similar bond mechanisms between the reference and EAF concrete specimens. Significant bond strength enhancement is observed in concretes with low w/c ratio, when EAF slag is used as recycled coarse aggregate. Experimental results in terms of bond strength were also compared to analytical predictions, obtained with empirical formulations.     

Accessible Ubiquitous Services for Supporting Daily Activities: A Case Study with Young Adults with Intellectual Disabilities

ABSTRACT

Ubiquitous environments have considerable potential to provide services supporting daily activities (using public transportation to and from workplace, using ATM machines, selecting and purchasing goods in ticketing or vending machines, etc.) in order to assist people with disabilities. Nevertheless, the ubiquitous service providers generally supply generic user interfaces which are not usually accessible for all potential end users. In this article, a case study to verify the adequacy of the user interfaces automatically generated by the Egoki system for two supporting ubiquitous services adapted to young adults with moderate intellectual disabilities was presented. The task completion times and the level of assistance required by participants when using the interfaces were analyzed. Participants were able to access services through a tablet and successfully complete the tasks, regardless of their level of expertise and familiarity with the service. Moreover, results indicate that their performance and confidence improved with practice, as they required fewer direct verbal and pointer cues to accomplish tasks. By applying observational methods during the experimental sessions, several potential improvements for the automated interface generation process were also detected.     

Automatic device-tailored evaluation of mobile web guidelines

Mobile web guidelines aim at providing developers with guidance to develop web content suitable for mobile devices. Automatic guideline review tools help evaluating conformance with respect to these guidelines in a systematic way. Yet, a number of mobile web guidelines refer to specific device features such as screen size, support for particular picture formats or support for pointing device. Since mobile devices are very diverse, in order to address the greater number of devices, guidelines adopt a device profile that may be considered as the common denominator device which is able to provide a satisfactory experience. While this approach is useful to define guidelines and make them more understandable, it introduces critical inaccuracies that make tool effectiveness decrease. This paper presents an application that considers specific device features in the evaluation process to produce device-tailored reports. As a result, higher rates of evaluation tool completeness, correctness and specificity are obtained.     

Activation of the Interleukin-33/ST2 Pathway Exerts Deleterious Effects in Myxomatous Mitral Valve Disease

Mitral valve disease (MVD) is a frequent cause of heart failure and death worldwide, but its etiopathogenesis is not fully understood. Interleukin (IL)-33 regulates inflammation and thrombosis in the vascular endothelium and may play a role in the atherosclerotic process, but its role in mitral valve has not been investigated. We aim to explore IL-33 as a possible inductor of myxomatous degeneration in human mitral valves. We enrolled 103 patients suffering from severe mitral regurgitation due to myxomatous degeneration undergoing mitral valve replacement. Immunohistochemistry of the resected leaflets showed IL-33 and ST2 expression in both valve interstitial cells (VICs) and valve endothelial cells (VECs). Positive correlations were found between the levels of IL-33 and molecules implicated in the development of myxomatous MVD, such as proteoglycans, extracellular matrix remodeling enzymes (matrix metalloproteinases and their tissue inhibitors), inflammatory and fibrotic markers. Stimulation of single cell cultures of VICs and VECs with recombinant human IL-33 induced the expression of activated VIC markers, endothelial–mesenchymal transition of VECs, proteoglycan synthesis, inflammatory molecules and extracellular matrix turnover. Our findings suggest that the IL-33/ST2 system may be involved in the development of myxomatous MVD by enhancing extracellular matrix remodeling.     

A framework for designing a supply chain distribution network

Based on the analysis of the pertinent literature, we propose a framework to serve as a guide in designing a distribution network as a component of a supply chain (SC). It consists of three steps that are common to goods and services SCs: position of the decoupling point, structure of the network, and product delivery. For each step, we take into account the peculiarities of both goods and services separately in order to establish a list of available options and evaluate their suitability in relation to the relevant factors that characterise the products and the markets.     

Kinetic study and hydrogen peroxide consumption of phenolic compounds oxidation by Fenton’s reagent

Synthetic solutions of phenol, o-, m- and p-cresol were oxidised by using Fenton’s reagent. The application of substoichiometric dosage of H₂O₂ led to the formation of intermediate compounds, continuing later the oxidation to complete oxidation. An important objective was to analyze the effect of hydrogen peroxide dosage applied and the reaction pH together with the iron oxidation state on the degradation level. A kinetic model was derived from a reaction mechanism postulated which was used to analyze the results of the experiments. Another aim was to analyze the hydrogen peroxide consumption. Noteworthy results include an increase in oxidant consumption to intensify phenol removal. Furthermore, oxidant consumption was analyzed through the ratio H₂O₂ to phenol removed and the average specific rate of removal (ASRR). By analyzing these two parameters it has been possible to ascertain the most favorable strategy for an efficient application of H₂O₂.     

Validating the effectiveness of EvalAccess when deploying WCAG 2.0 tests

While automatic tools are not intended to replace human judgment, they are crucial in order to develop accessible websites. The release of WCAG 2.0 has caused great expectation, as it is supposed to be precisely testable with automated review tools. Therefore, more effective tools could be developed. However, so far few tools applying WCAG 2.0 have been developed. This paper presents an evaluation framework which has been updated in order to evaluate the new tests. In addition, it describes a validation process carried out in order to verify the effectiveness of the new version of the evaluation tool. The effectiveness is validated by conducting a quantitative and qualitative analysis of the results obtained by applying both versions of the tool (the one implementing WCAG 1.0 and the one implementing WCAG 2.0) to a set of selected web pages, as well as by manual evaluation of an expert for detecting the possible false positives and false negatives produced by each tool.     

Role of Grafting on Particle and Film Morphology and Film Properties of Zero VOC Polyurethane/Poly(meth)acrylate Hybrid Dispersions

Hybrid waterborne dispersions of polyurethane (PU)/poly(meth)acrylic are widely applied in coating and adhesive products, as well as in many other applications. The synergetic performance of the two component polymers is highly dependent on the ability to control the PU and (meth)acrylic network structure. In this work, the effect of grafting and the impact of macromolecular architecture on the particle and film morphology as well as on the properties of PU/(meth)acrylic hybrid films is investigated. It is shown that with grafting, the absolute molar mass distribution (MMD) is shifted toward higher values as the low molar mass PU chains become incorporated in the (meth)acrylic polymer network. Furthermore, by using different types of functional monomers, the nature of the MMD can be altered. Using transmission electron microscopy (TEM) analysis, it is demonstrated that more homogeneous particle and film morphologies are obtained in the case of grafted hybrids. Finally, the impact of network structure on tensile strength is outlined highlighting that grafted polymer films have higher Young's modulus and strain hardening than the non‐grafted ones.