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Nowadays, many construction companies use maturity-based approaches to support decisions that have strong impact on costs and sustainability of the construction process, such as: age of pre-stressing operations, decision of propping/formwork removal; instant of subjection to load, etc. Current approaches to quality control through maturity consist in evaluating the compressive strength evolution of the concrete mix at a reference curing temperature (usually 20°C), together with the determination of the apparent activation energy (Ea) of the mix. The value of Ea is usually obtained from one of these three sources: (i) reference recommendations based on the type of cement; (ii) calorimetric testing; (iii) testing of compressive strength evolution at several distinct temperatures. The only technique of determining Ea that really addresses a mechanical property is the latter one, demanding however the deployment of many specimens and tests. Furthermore, the destructive character of this technique limits the possibility of maintaining the same specimen for the entire Ea testing, thus increasing the variability/scattering of results. The present study intended to evaluate the possibility of assessing mechanical-based activation energy for concrete through continuous or quasicontinuous assessments of E-modulus since very early ages. E-modulus is a mechanical property depending on the advancement of the hydration reaction and the temperature stories during the curing, with the interesting characteristic of allowing non-destructive testing to be carried out. This paper presents an inter-laboratory and inter-technique comparative study of E-modulus evolution at several temperatures. Three laboratories were involved, contributing with specific testing techniques applied to a single mix of normal strength concrete: 1) BTJASPE (BéTon au Jeune Age, Suivi de la Prise et du module d'Elasticité), available at IFSTTAR in France; 2) EMM-ARM (Elasticity Modulus Measurement through Ambient Response Method) available at the University of Minho in Portugal; 3) TSTM (Temperature Stress Testing Machine), available at Université Libre de Bruxelles in Belgium. Fundação para a Ciência e a Tecnologia (FCT)

Dielectric elastomers are highly promising as functional materials for the rapidly developing field of flexible actuator and generator technology. They offer a unique combination of low densities and large reversible deformations of up to more than 100% in area, and consequently have great potential for many new types of application. However, implementation has been impeded by the lack of specialized materials. The elastomers that have so far been investigated suffer from a number of disadvantages, including the need for very high activation voltages and limited service lifetimes. This thesis describes an investigation of the use of elastomeric composites as dielectric elastomers with the aim of optimizing and improving their performance in actuators. The influence of materials properties on actuation was first analyzed on the basis of a simple physical model and materials properties derived from standard test methods. The implications for the actuation performance of three conventional dielectric elastomers were then considered in detail. A preliminary conclusion was that the actuation performance could be improved if the permittivity of the elastomers were to be increased by modification with ceramic or conductive fillers. However, actuation performance was shown to depend not only on the permittivity, but also on the elastic modulus, the electrical breakdown strength, and strain hardening. Thus, although significant increases in permittivity were achieved by this approach, actuation performance was compromised by an increase in modulus in the case of the ceramic fillers, and a dramatic drop in electrical breakdown strength, in the case of the conducting fillers. A more promising approach was therefore suggested to be the use of an organic conducting filler encapsulated in an insulating matrix. It was demonstrated that it is indeed possible to increase the permittivity of a given elastomer while maintaining a high electrical breakdown strength. Different processing routes were investigated in order to control the dispersion of the filler and tailor performance. The optimum filler concentration, i.e. that providing the best compromise between permittivity and stiffness, was determined to be approximately 16 vol%, resulting in an improvement by a factor of 2 in actuation strain for a given applied voltage over that obtained with the unmodified matrix. Higher filler concentrations were also argued to have considerable potential for use in generators, given that the observed increased permittivity was also associated with high electrical breakdown strengths and increased strains at break. A threefold increase in converted energy per working cycle was predicted for a composite containing 25.5 vol% fillers based on a simplified model for a dielectric elastomer generator. Whilst these results are extremely encouraging, it is concluded that the composite approach has, in general, only limited potential as a means of obtaining further increases in actuation performance. The major difficulty remains that the use of a relatively rigid second phase to increase dielectric performance will inevitably also increase the elastic modulus beyond a certain filler concentration. As argued in the final part of the thesis, the way forward may therefore ultimately depend on the development of new types of synthetic elastomeric matrix materials that combine intrinsic improvements in electrical response with reduced moduli.

Le Meillour & Sinet-Mathiot et al. 2024 Increasing sustainability in palaeoproteomics by optimizing digestion times for large-scale archaeological bone analyses DOI: 10.1016/j.isci.2024.109432 MALDI-ToF MS data (raw data: mzML files, merged spectra: msd files) used for the ZooMS analysis of the bone material from Baishiya Karst Cave (China) and La Draga (Spain), along with the R codes for merging triplicates into one msd file. 

Sustainability assessment and rating systems are intended to foster more sustainable design, construction, operation, maintenance and disassembly/deconstruction promoting and making possible a better integration of environment, societal, and cost concerns with other traditional decision criteria. The use of improved and building technologies can contribute considerably to better environmental cycle and then to the sustainability of the constructions. It is widely recognised in the of Building Sustainability Assessment that Life Cycle Assessment (LCA) is a much preferable method for evaluating the environmental pressure caused by materials, Building assemblies and the whole life-cycle of a building. Nevertheless, LCA tools are not extensively used in building design and most of building sustainability assessment and systems are not comprehensive or consistently LCA-based. Reasons for this failure above all related to the huge variety and amount of material flows and processes of building’s Lifecycle and to the complexity of the stages of a LCA. This paper will present the difficulties and possible solutions to integrate more accurate environmental methods in rating systems. In this context, the paper will also present the work that is being carried out in the development of the Portuguese Building Sustainability Assessment system (SBTool PT)

Obesity is a growing health problem concerning much of the human civilization. Fundamental research into the underlying mechanisms of body weight regulation can open new paths that will lead to a larger array of treatment options. Leptin is a hormone that plays a crucial role in body weight regulation. It is known for reducing food intake and increasing energy expenditure via leptin receptor (LepR) signalling in the brain. Although leptin is known for reducing food intake, this thesis describes the variable effects of leptin on feeding in mice: after leptin injections, some mice decreased feeding, while others increased feeding. Even more, the feeding effect of leptin predicted how much weight a mouse gained on a high caloric diet: mice that increased feeding with leptin, gained more weight and vice versa. This thesis further addresses how LepR-neurons (neurons that are responsive to leptin) of different brain areas influence aspects of body weight regulation: food consumption, motivation to work for food reward, locomotor activity and body temperature. To do so, we used chemogenetics, which is a technique with which we can temporarily activate LepR-neurons of a certain brain area and examine the effect of this activation on behavioural tasks. We found that the four studied LepR-containing brain areas differently affect aspects of body weight regulation. This thesis sheds more light on how leptin and LepR-neurons influence body weight. With this we hope to contribute to exciting new discoveries that will aid in the reduction of the obesity pandemic.

We report on the properties of Eu-doped ZnO nanorods prepared by chemical bath deposition from aqueous solutions in an autoclave. The autoclave enables to grow the nanorods above the boiling point of water. The nanorods were characterized by scanning electron microscopy, secondary ion mass spectroscopy, and low temperature photoluminescence spectroscopy. Under the UV light excitation, the nanorods show a strong blue emission at 450 nm, which is associated with the 4f(6)5d - 4f(4) transitions of Eu2+ ions. We discuss the mechanisms responsible for the blue luminescence. We further clarify how the growth parameters affect the morphology and the optical properties of the nanorods. Growth temperatures above the boiling point of water significantly influence the intensity ratio of the near band edge emission to the deep level emission and greatly enhance optical quality of the nanorods.

Abundance and taxonomic assignments from 3 Pyrosequencing runs, and 1 MiSeq run for chapters 2-5 of PhD Thesis. Data provided in tab- separated text format.

The Coast to Karoo Transect investigates the abundance and diversity of ants and beetles along an altitudinal gradient in the Cederberg mountains of the Western Cape, South Africa. It is a long term project, initiated in 2002 by Prof. S.L. Chown, Stellenbosch University. Data collection is carried out on a biannual (spring and autumn) basis. To monitor changes in invertebrate assemblages, focusing on ants and beetles.