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Multicomponent cement-based composites are known as versatile structural materials for enhanced radiation shielding. The use of selected elements, like boron, cadmium, or rare earth elements, provides an increased neutron shielding capacity. Because of profusion, reasonable costs and large cross-section for neutron capture, boron containing minerals are suggested as aggregates for radiation shielding concrete. Despite many advantages, boron additives may act as cement setting retarders. Uncontrolled setting and hardening is not acceptable in radiation shielding concrete technology. In this work we present results from isothermal calorimetry measurements on cement mortars with boron-containing aggregates. Four types of boron aggregates were used in the studies: colemanite, ulexite, borax and boron carbide. Based on calorimetric curves, the beginning of setting time was determined. Additionally early mortar strength was investigated and linear relationship between the heat generated in the isothermal calorimeter and the early compressive strength has been observed. The use of isothermal calorimetry allowed us to estimate the limits for the content of boron compounds to be used cement mortar.

Moving load is a fundamental loading pattern for many civil engineering structures and machines. This paper proposes and experimentally verifies an approach for indirect identification of 2D trajectories of moving loads. In line with the "structure as a sensor" paradigm, the identification is performed indirectly, based on the measured mechanical response of the structure. However, trivial solutions that directly fit the mechanical response tend to be erratic due to measurement and modeling errors. To achieve physically meaningful results, these solutions need to be numerically regularized with respect to expected geometric characteristics of trajectories. This paper proposes a respective multicriterial optimization framework based on two groups of criteria of a very different nature: mechanical (to fit the measured response of the structure) and geometric (to account for the geometric regularity of typical trajectories). The state-of-the-art multiobjective genetic algorithm NSGA-II is used to find the Pareto front. The proposed approach is verified experimentally using a lab setup consisting of a plate instrumented with strain gauges and a line-follower robot. Three trajectories are tested, and in each case the determined Pareto front is found to properly balance between the mechanical response fit and the geometric regularity of the trajectory.

Background: Patient-reported outcomes (PROs) are increasingly used to demonstrate the value of interventions and support health technology assessment (HTA)., Objective: The objective of this work was to analyze trends regarding PROs in Latin America (LatAm), highlight challenges in the application of PROs in this region, and suggest solutions., Methods: A team of researchers with expertise in PROs conducted a nonsystematic PubMed literature search pertaining to the use of PROs in LatAm. The experts also drew on their experience working with PROs to assess the application of PROs in LatAm., Results: The literature search yielded more than 4000 publications, with an increasing publication rate in recent years. PROs are being used in LatAm in various study types: instrument validation, phase III international clinical trials, health service research. A large Inter-American Development Bank study demonstrates the growing importance of PROs in the region. The growth in local value sets for the EuroQol five-dimensional questionnaire in LatAm reflects the regional emergence of HTA systems. Operational challenges relate to ensuring the use of good-quality questionnaires that, at a minimum, have undergone appropriate cultural adaptation and ideally have established psychometric properties., Conclusions: PROs are increasingly important in LatAm. Future efforts should aim to strengthen the operational and research infrastructure around PROs in the region. Innovation should be encouraged, including studying alternative methods of eliciting health utilities for economic evaluation. A wider scope around PRO uses for decision making by HTA bodies is an international trend with potential positive prospects in LatAm., (Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)