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We investigated the corrosion properties and transpassive behavior of CrMnFeCoNi and CrCoNi multi‐principal element alloys (MPEAs) in a 0.1 M NaCl electrolyte at pH 12. By using SECM‐based tip substrate voltammetry (TSV) in combination with the chemical analysis of the electrolyte, we were able to differentiate between anodic metal dissolution and oxygen evolution in the transpassive range. Our investigations have shown that CrCoNi has a significantly higher corrosion resistance compared to CrMnFeCoNi. In the studied alkaline environment, a transpassive oxide film is formed on the surface of CrCoNi during secondary passivation. This transpassive oxide film appears to play a significant role in oxygen evolution, as the increase in TSV currents at the microelectrode coincides with the corresponding current density plateau of the voltametric current trace. The formation of the transpassive oxide film was not observed in previous studies conducted in acidic environments. Moreover, the alkaline electrolyte induced a positive hysteresis and mild pitting corrosion, in addition to intergranular corrosion, which was the sole corrosion process observed at acidic pH levels. These findings enhance the understanding of the processes governing the transpassivity of CrMnFeCoNi and CrCoNi MPEAs in alkaline environments and have potential implications for the development of application‐tailored corrosion‐resistant MPEAs. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic, a global health crisis, was acutely felt in the labour market for many young workers. Importantly, precarious employment, identified as an emergent social determinant of health, may negatively affect the mental health and well-being of young workers. To this end, we engaged with young workers to understand their workplace needs and challenges in the COVID-19 era and hear their recommendations for action. Semi-structured interviews and a graphic recording focus group were conducted with 33 young workers aged 18–26 years old in Manitoba, Canada, who had worked a minimum of 30 hours per week prior to COVID-19 onset and were living independent of their parents. Analysis involved delineating units of meaning from the data, clustering these to form thematic statements and extracting themes. Second-level analysis involved applying themes and sub-themes to a social determinants of health framework. The multifaceted, compounding realities of young workers' pre-COVID-19 employment situations were amplified by the COVID-19 pandemic, adversely impacting young worker's mental health. Unique findings from this study highlight the generational differences in this cohort, who are opposed to participating in fragmented systemic structures (neoliberalism) and inequitable employment conditions, and who yearn for social inclusion and work-life balance. Their recommendations for government and employers call for permanent and stable employment opportunities, economic and mental health supports, and space to be heard and valued, as they navigate the many life course challenges as emerging adults. Societies are dependent on young workers to develop and support the Canadian economy for future generations. Thus, it is a critical that recommendations proposed by young workers in this study be acted upon and implemented to provide an equitable, stable, and supportive future for young workers in Canada and beyond. [ABSTRACT FROM AUTHOR]

We describe and demonstrate a novel experimental approach to measure broadband, amplitude- and phase-resolved scattering spectra of single nanoparticles with 10-nm spatial resolution. Nanofocusing of surface plasmon polaritons (SPPs) propagating along the shaft of a conical gold taper is used to create a spatially isolated, spectrally broad nanoscale light source at its very apex. The interference between these incident SPPs and SPPs that are backpropagating from the apex leads to the formation of an inherently phase-stable interferogram, which we detect in the far field by partially scattering SPPs off a small protrusion on the taper shaft. We show that these interferograms allow the reconstruction of both the amplitude and phase of the local optical near fields around individual nanoparticles optically coupled to the taper apex. We extract local light scattering spectra of particles and quantify line broadenings and spectral shifts induced by tip-sample coupling. Our experimental findings are supported by corresponding finite-difference time-domain and coupled dipole simulations and show that, in the limit of weak tip-sample coupling, the measurements directly probe the projected local density of optical states of the plasmonic system. The combination of a highly stable inline interferometer with the inherent optical background suppression through nanofocusing makes it a promising tool for the locally resolved study of the spectral and temporal optical response of coupled hybrid nanosystems.

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Multi‐principal element alloys (MPEAs) are gaining interest in corrosion and electrocatalysis research due to their electrochemical stability across a broad pH range and the design flexibility they offer. Using the equimolar CrCoNi alloy, we observe significant metal dissolution in a corrosive electrolyte (0.1 M NaCl, pH 2) concurrently with the oxygen evolution reaction (OER) in the transpassive region, despite the absence of hysteresis in polarization curves or other obvious corrosion indicators. We present a characterization scheme to delineate the contribution of OER and alloy dissolution, using scanning electrochemical microscopy (SECM) for OER‐onset detection, and quantitative chemical analysis with inductively coupled‐mass spectrometry (ICP‐MS) and ultraviolet visible light (UV/Vis) spectrometry to elucidate metal dissolution processes. In situ electrochemical atomic force microscopy (EC‐AFM) revealed that the transpassive metal dissolution on CrCoNi is dominated by intergranular corrosion. These results have significant implications for the stability of MPEAs in corrosion systems, emphasizing the necessity of analytically determining metal ions released from MPEA electrodes into the electrolyte when evaluating Faradaic efficiencies of OER catalysts. The release of transition metal ions not only reduces the Faradaic efficiency of electrolyzers but may also cause poisoning and degradation of membranes in electrochemical reactors. [ABSTRACT FROM AUTHOR]

Sensing the scattered fields of single metallic nanostructures is a crucial step towards the applications of isolated plasmonic antennas, such as for the sensing of single molecules or nanoparticles. In the past, both near- and far-field spectroscopy methods have been applied to monitor single plasmonic resonances. So far, however, these spectral-domain techniques do not yet provide the femtosecond time resolution that is needed to probe the dynamics of plasmonic fields in the time domain. Here, we introduce a time-domain technique that combines broadband Fourier-transform spectroscopy and spatial modulation spectroscopy (FT-SMS) to quantitatively measure the extinction spectra of the isolated gold nanorods with a nominal footprint of 41×10 nm2. Using a phase-stable pulse pair for excitation, the technique is capable of rejecting off-resonant stray fields and providing absolute measurements of the extinction cross section. Our results indicate that the method is well suited for measuring the optical response of strongly coupled hybrid systems with high signal-to-noise ratio. It may form the basis for new approaches towards time-domain spectroscopy of single nanoantennas with few-cycle time resolution.

Introduction: Rural recruitment and retention continues to present challenges to health workforce planners. This paper reports and analyzes the results of a survey sent to physicians in Manitoba, eliciting their opinions regarding rural jobs. Methods: A survey was sent to all physicians in Manitoba. Part 1 of the survey included questions about background and demographic information; part 2 was a set of job satisfaction questions regarding respondents' current job; and part 3 included 2 sets of stated-choice questions eliciting preferences for a set of attributes relevant to rural recruitment and retention. Results: Of the 2487 physicians who received surveys, 561 (22.6%) responded. Respondents indicated that income, hours worked and on-call frequency are very important: overall job satisfaction increased with income and decreased with hours worked. Income, hours and on-call frequency were ranked 'very important' by the largest proportions of physicians. The estimated compensation for on-call more frequent than 1-in-4 was very high (82% of average income), and additional hours worked were worth $183 per hour. Other attributes that were important included professional interaction, housing availability and community incentives during the first year, which were valued at 11%--31% of annual income. Conclusion: Work-life balance is a key consideration for rural jobs, and there are incentives that can compensate for less desirable attributes. Introduction: Le recrutement et le maintien en poste continuent d'etre une source de defies pour les planificateurs des ressources humaines en sante. Cet article presente et analyse les resultats d'un sondage sur le travail en milieu rural mene aupres de medecins au Manitoba. Methodes: Un questionnaire a ete envoye a tous les medecins au Manitoba. La partie 1 du questionnaire recueillait des renseignements demographiques et generaux; la partie 2 presentait un ensemble de questions sur la satisfaction professionnelle des repondants a l'egard de l'emploi actuel; la partie 3 contenait 2 series de questions a choix fixes pour determiner les preferences en regard d'aspects pertinents au recrutement et au maintien en poste en milieu rural. Resultats: Sur les 2487 medecins ayant recu le questionnaire, 561 (22,6 %) ont repondu. Les repondants ont indique que le revenu, les heures de travail et la frequence du service de garde sont tres importants : le taux de satisfaction generale augmentait en fonction du revenu et diminuait selon le nombre d'heures de travail. Le revenu, les heures de travail et la frequence du service de garde etaient consideres comme etant << tres importants >> par le nombre le plus eleve de medecins. La remuneration estimee pour un service de garde de frequence superieure a un rapport d'un sur quatre etait tres elevee (82 % du revenu moyen), et la valeur accordee a chaque heure supplementaire etait de 183 $ l'heure. Parmi les autres aspects juges importants, mentionnons l'interaction professionnelle, la disponibilite de logements et des mesures incitatives communautaires la premiere annee, le tout evalue a 11 %-31 % du revenu annuel. Conclusion: L'equilibre entre le travail et la vie personnelle est un facteur cle pour les emplois en milieu rural et il existe des mesures incitatives pour compenser les caracteristiques moins desirables., INTRODUCTION The physician-to-population ratio in Canada has been well below the Organisation for Economic Co-operation and Development average for many years. (1) A recent report by the Canadian Institute for [...]