RESUMEN
In vivo models are used in biomedical research to reproduce human disease and develop new drugs. However, they do not mimic the disease as it occurs in humans, and their use has failed to identify novel therapies effective for many highly prevalent non-communicable diseases, such as Alzheimer's disease. Indeed, the clinical failure rate in drug development remains very high, with an overall likelihood of approval from Phase I of about 9.6%. On the other hand, human-based models, advanced imaging techniques and human epidemiological studies may increase our understanding of disease aetiology and pathogenesis and enable the advance of safe and effective therapies. Particularly when human tissues are used, they may produce faster, cheaper results, more predictive for humans, whilst yielding greater comprehensions of human biochemical processes. A first effort to collect existing knowledge about non-animal models of highly prevalent human diseases was made by the Joint Research Centre of the European Commission. The final aim was to identify and share information on the capabilities and limits of human-based models at different levels: scientific communities, universities and secondary schools, national committees for animal welfare and the public at large.
RESUMEN
Two stainless steel anodes, AISI 420 and AISI 310, and pure iron were compared in an electrocoagulation study for the simultaneous removal of phosphates, Orange II and Zinc ions from a synthetic wastewater at a current density of 11.7 mA cm-2 and a surface area to volume ratio of 19.4 m-1. High removal efficiencies were observed with AISI 420 and pure iron, reaching values between 88% and 99%, while significantly lower values, approximately 30%, were obtained with AISI 310. The AISI 310 performed well in the removal of Zn2+ due to its removal as Zn(OH)2. The variations in the performance of the steel anodes were attributed to the lower chromium content of the AISI 420, which gives less passive behaviour. This was supported using polarisation data, where a 10-fold increase in the corrosion current was obtained for AISI 420 compared to AISI 310. Furthermore, Cr(VI) was observed in the solution phase when AISI 310 was employed as the anode, illustrating the importance of the alloying concentrations. While rust particles were seen during the non-continuous use of the iron anode, they were not observed with the AISI 420 anode.
RESUMEN
The simultaneous removal of phosphates, Zn2+ and Orange II, in two synthetic wastewaters was achieved using Al-Mg and Al-Zn-In alloys as anodes at 11.7 mA cm-2 and a surface area to volume ratio of 19.0 m-1. Higher removal efficiencies were obtained with Al-Zn-In, attaining values of 95-96% for phosphate, 99% for Zn2+ and 88-96% for Orange II, while somewhat lower values were seen with Al-Mg, with 89-93% for phosphate, 96% for Zn2+ and 50-60% for Orange II, depending on the solution. The higher efficiency with Al-Zn-In was attributed to its less passive behaviour, which was evident from polarisation plots. Numerous shallow pits, resembling general-like dissolution, were seen with Al-Zn-In, while fewer and larger pits were observed with Al-Mg. The energy demand for the removal of the pollutants was computed as 1.30 and 2.55â¯kWh m-3 for the Al-Zn-In and Al-Mg anodes, respectively. The removal of phosphates and Orange II was explained in terms of the generation of cationic polynuclear aluminium species that provide electrostatic interactions with the anionic phosphates and Orange II. The removal of Zn2+ was attributed to the formation of insoluble Zn(OH)2.