TY - JOUR A1 - Pieres, A. A1 - Almeida, Ângela A1 - Correia, J. A1 - Calisto, V. A1 - Schneider, Rudolf A1 - Esteves, V. I. A1 - Soares, A. M. V. M. A1 - Figueira, E. A1 - Freitas, R. T1 - Long-term exposure to caffeine and carbamazepine: Impacts on the regenerative capacity of the polychaete Diopatra neapolitana N2 - The toxicity induced in non-target organisms by pharmaceutical drugs has been the focus of several studies. In the aquatic environment, most of the studies have been devoted to fish and bivalves, while little is known on the impacts induced in polychaetes. The present study evaluated the impacts of carbamazepine and caffeine on the regenerative capacity of Diopatra neapolitana, a polychaete species with high ecological and economic relevance. Under laboratory controlled conditions polychaetes were exposed, during 28 days, to carbamazepine (Ctl-0.0; 0.3; 3.0; 6.0; 9.0 mg/L) and caffeine (Ctl-0.0; 0.5; 3.0; 18.0 mg/L). During the experiment, at days 11, 18, 25, 32, 39 and 46 after amputation, for each specimen, the percentage of the body width regenerated was determined and the number of new segments was counted. The regenerative capacity was assessed considering the number of days needed to achieve full regeneration and the total number of new segments. The obtained results revealed that with the increase of drugs concentrations organisms regenerated less new segments and took longer to completely regenerate. KW - Diopatra neapolitana KW - Pollution KW - Pharmaceutical drugs KW - Regenerative capacity PY - 2016 DO - https://doi.org/10.1016/j.chemosphere.2015.12.035 SN - 0045-6535 VL - 146 SP - 565 EP - 573 PB - Elsevier AN - OPUS4-38497 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brás, A. R. A1 - Noronha, J. P. A1 - Antunes, A. M. M. A1 - Cardoso, M. M. A1 - Schönhals, Andreas A1 - Affouard, F. A1 - Dionísio, M. A1 - Correia, N.T. T1 - Molecular motions in amorphous Ibuprofen as studied by broadband dielectric spectroscopy N2 - The molecular mobility of amorphous ibuprofen has been investigated by broadband dielectric relaxation spectroscopy (DRS) covering a temperature range of more than 200 K. Four different relaxation processes, labeled as α, β, γ, and D, were detected and characterized, and a complete relaxation map was given for the first time. The γ-process has activation energy Ea = 31 kJ·mol-1, typical for local mobility. The weak β-relaxation, observed in the glassy state as well as in the supercooled state was identified as the genuine Johari-Goldstein process. The temperature dependence of the relaxation time of the α-process (dynamic glass transition) does not obey a single VFTH law. Instead two VFTH regimes are observed separated by a crossover temperature, TB = 265 K. From the low temperature VFTH regime, a Tgdiel(t =100 s) = 226 K was estimated, and a fragility or steepness index m = 93, was calculated showing that ibuprofen is a fragile glass former. The D-process has a Debye-like relaxation function but the temperature dependence of relaxation time also follows the VFTH behavior, with a Vogel temperature and a pre-exponential factor which seem to indicate that its dynamics is governed by the α-process. It has similar features as the Debye-type process observed in a variety of associating liquids, related to hydrogen bonding dynamics. The strong tendency of ibuprofen to form hydrogen bonded aggregates such as dimers and trimers either cyclic or linear which seems to control in particular the molecular mobility of ibuprofen was confirmed by IR spectroscopy, electrospray ionization mass spectrometry, and MD simulations. PY - 2008 DO - https://doi.org/10.1021/jp8040428 SN - 1520-6106 SN - 1520-5207 SN - 1089-5647 VL - 112 IS - 35 SP - 11087 EP - 11099 PB - Soc. CY - Washington, DC AN - OPUS4-17866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fernádez-Canteli, A. A1 - Castillo, E. A1 - Blasón Gonzalez, Sergio A1 - Correia, J. A. F. O. A1 - de Jesus, A. M. P. T1 - Generalization of the Weibull probabilistic compatible model to assess fatigue data into three domains: LCF, HCF and VHCF N2 - n this work, three classes of fatigue models are reviewed according to the fatigue regimes commonly considered in the current components design. Particular attention is devoted to the so-called Class III fatigue models, covering the three fatigue regimes, namely, LCF, HCF and VHCF. The applicability and limitations of the pro-posed analytical sigmoidal solutions are discussed from the viewpoint of practical design. The compatible Weibull S-N model by Castillo and Canteli is revisited and improved by considering a new reference parameter GP = E⋅σM ⋅(dε/dσ)|M as the driving force alternative to the conventional stress range. In this way, the requirement, σM ≤ σu, according to the real experimental conditions, is fulfilled and the parametric limit number of cycles, N0, recovers its meaning. The probabilistic definition of the model on the HCF and VHCF regimes is maintained and extended to the LCF regime. The strain gradients may be calculated from the monotonic or cyclic stress–strain curve of the material although a direct derivation from the hysteresis loop is recommended. Some Class III fatigue models from the literature and another one improved by the authors are applied to the assessment of one experimental campaign under different stress ratios conditions and the results compared accordingly. Finally, the new probabilistic GP-N field is evaluated. The results confirm the practical confluence of the stress- and the strain-based approaches into a single and advantageous unified methodology. KW - LCF region KW - S-N probabilistic field KW - Energetic reference parameter PY - 2022 DO - https://doi.org/10.1016/j.ijfatigue.2022.106771 SN - 0142-1123 VL - 159 SP - 1 EP - 18 PB - Elsevier Ltd. AN - OPUS4-55235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -