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Abstract: This work investigates the formation of oxidation by-products during the electrochemical removal of ammonium using BDD electrodes from wastewaters containing chlorides. The influence of the initial chloride concentration has been experimentally analyzed first, working with model solutions with variable ammonium concentration and second, with municipal landfill leachates. Two different levels of chloride concentration were studied, i) low chloride concentrations ranging between 0 and 2000 mg/L and, ii) high chloride concentrations ranging between 5000 and 20,000 mg/L. Ammonium removal took place mainly via indirect oxidation leading to the formation of nitrogen gas and nitrate as the main oxidation products; at high chloride concentration the formation of nitrogen gas and the rate of ammonium removal were both favored. However, chloride was also oxidized during the electrochemical treatment leading to the formation of free chlorine responsible of the ammonium oxidation, together with undesirable products such as chloramines, chlorate and perchlorate. Chloramines appeared during the treatment but they reached a maximum and then started decreasing, being totally removed when high chloride concentrations were used. With regard to the formation of chlorate and perchlorate once again the concentration of chloride exerted a strong influence on the formation kinetics of the oxidation by-products and whereas at low chloride concentrations, chlorate appeared like an intermediate compound leading to the formation of perchlorate, at high chloride concentrations chlorate formation was delayed significantly and perchlorate was not detected during the experimental time. Thus this work contributes first to the knowledge of the potential hazards of applying the electro-oxidation technology as an environmental technology to deal with ammonium oxidation under the presence of chloride and second it reports efficient conditions that minimize or even avoid the formation of undesirable by-products. [Copyright &y& Elsevier]

Abstract: To develop reliable integrated power electronics, it is paramount to consider the coupling between electrical, thermal and mechanical effects. Though essential for final validation, experimental analysis is time-consuming, especially when trying out new designs. Simulative approaches at multi-domain physical analysis need to be improved. In this work, a platform is proposed, in which all physics are treated with dedicated simulation programmes, co-ordinated by a custom-developed core section. A case study, based on a novel integrated power switch developed for railway traction applications, demonstrates the validity of the envisaged solution for virtual reliability assessment. [Copyright &y& Elsevier]

Background: Ventricular fibrillation (VF) has been proposed to be maintained by localized high-frequency sources. We tested the hypothesis that combined spectral and nonlinear analyses of the standard ECG enables accurate localization of VF sources. Methods: Six precordial ECG leads were used to record from 10 ischemic cardiomyopathy (IC) and 15 Brugada syndrome (BrS; type 1 ECG) patients during VF. Fourier and Hilbert transforms of ECG waveforms were used for frequency and phase analyses, respectively. Results: Despite temporal variability, induced VF episodes recorded for 19.9 ± 8.6 seconds displayed long-lasting periods (7.8 ± 2.1 seconds [range 4.9–12.8 seconds]) of spectral power at a common frequency (shared frequency [SF]) in all leads (5.9 ± 0.8 Hz). In BrS patients, phase analysis of the SF showed a V1–V6 activation sequence as would be expected from waves originating at the base of the ventricles in patients displaying a type 1 ECG pattern (Friedman P <.001). Hilbert-based phase comparison confirmed that the V1–V6 sequence was the most stable over the whole VF duration. However, phase analysis of the SF in IC patients with anteroseptal (n = 4), apex (2), and lateral (4) myocardial infarction displayed activation at V1–V2, V3–V4, and V5–V6 as the earliest, respectively, consistent with an activation originating from the scar location (P <.01). The observed patterns correlated with the more stable sequence observed during Hilbert-based phase analysis (P <.05). Paired comparison showed that phase sequences were similar during monomorphic ventricular tachycardia and VF (Pearson coefficient 0.58, P <.001). Also, a dominant frequency gradient was observed between precordial leads corresponding to the scar region and the contralateral leads (5.86 ± 0.9 Hz vs 5.44 ± 1.1 Hz; paired t-test P = .011). Conclusions: Early VF in BrS and IC patients is characterized by a steady sequence in the phase-frequency domain consistent with anatomic location of the arrhythmogenic substrate. These results are consistent with the prediction that VF is maintained by a small number of high-frequency sources that interact with the surrounding myocardium to generate fibrillatory conduction. [Copyright &y& Elsevier]

Abstract: Based on the on-state voltage drop monitoring at high current, an alternative method for thermo-sensitive parameters calibration is reported. The main goal is that it allows the simultaneous calibration of the series resistance and power devices voltage drop on temperature. Thereby, the average temperature over all power devices and the temperature difference in average inside the pack can be measured in real applications. [Copyright &y& Elsevier]

The European Space Agency (ESA) Planetary Science Archive (PSA) is undergoing a significant refactoring of all its components to improve the services provided to the scientific community and the public. The PSA supports ESA's missions exploring the Solar System by archiving scientific peer-reviewed observations as well as engineering data sets. This includes the Giotto, SMART-1, Huygens, Venus Express, Mars Express, Rosetta, Exomars 2016, Exomars RSP, BepiColombo, and JUICE missions. The PSA is offering a newly designed graphical user interface which is simultaneously meant to maximize the interaction with scientific observations and also minimise the efforts needed to download these scientific observations. The PSA still offers the same services as before (i.e., FTP, documentation, helpdesk, etc.). In addition, it will support the two formats of the Planetary Data System (i.e., PDS3 and PDS4), as well as providing new ways for searching the data products with specific metadata and geometrical parameters. As well as enhanced services, the PSA will also provide new services to improve the visualisation of data products and scientific content (e.g., spectra, etc.). Together with improved access to the spacecraft engineering data sets, the PSA will provide easier access to scientific data products that will help to maximize the science return of ESA's space missions. [ABSTRACT FROM AUTHOR]

The objective is to conduct a longitudinal analysis of the effects of the pandemic and alarm situation on the mental health of the general population at three points in time: two weeks after beginning the confinement, after a month, and after two months, when the lockdown was lifted and the country returned to the new normality. The evaluations were carried out by means of an online survey, with a sample of 3480 persons in the first data collection and 1041 and 569 persons in the successive evaluation periods. The presence of depressive symptoms, anxiety and posttraumatic stress disorder (PTSD) was evaluated by means of screening tests. Sociodemographic data, Covid-19 variables, loneliness, psychological well-being, social support, discrimination and a sense of belonging, were collected. Depressive symptoms increased significantly throughout the confinement, decreasing at the last assessment but not dropping to previous levels. In anxiety, there are no significant changes between the three evaluations, but a downward trend can be seen over time. Regarding the symptomatology of PTSD, a downward trend is observed throughout the three evaluations, with significantly lower scores between the first and third assessments. The different regression models developed reveal the importance of perceived loneliness and spiritual well-being as the main predictors of mental health, as well as the importance of the lower age for depression and the female gender for anxiety and PSTD. This research shows that the pandemic has had a negative impact on our mental health, which still does not seem to be at pre-crisis levels, although it has improved as the emergency situation subsides. These results underline the importance of paying greater attention to mental health, and reveal key variables such as spiritual well-being and perceived loneliness in which to intervene from different care services, as well as younger people and women as vulnerable groups on which to focus more attention. • Covid-19 had a strong impact on the mental health throughout the confinement. • Depression decreased over time, although it did not reach previous levels. • Anxiety remains but a downward trend is observed, and PSTD decreases significantly. • Women and youth have been most affected by the pandemic. • Loneliness and well-being are key variables in predicting mental health impact. [ABSTRACT FROM AUTHOR]