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An inter-comparison of Arctic synoptic scale storms between four global reanalysis datasets
The Arctic is becoming more accessible as sea ice extent continues to decline, resulting in higher human exposure to Arctic storms. This study compares Arctic storm characteristics between the ECMWF-Interim Reanalysis, 55-year Japanese Reanalysis, NASA-Modern Era Retrospective Analysis for Research and Applications Version 2 and National Centre for Environmental Prediction-Climate Forecast System Reanalysis datasets between 1980 and 2017, in winter (DJF) and summer (JJA). It is shown that Arctic storm characteristics are sensitive to the variable used for storm tracking. Arctic storm frequency is found to be similar in summer and winter when using sea level pressure minima to track Arctic storms, whereas, the storm frequency is found to be higher in winter than summer when using 850 hPa relative vorticity to track storms, based on using the same storm tracking algorithm. It is also found that there are no significant trends in Arctic storm characteristics between 1980 and 2017. Given the sparsity of observations in the Arctic, it might be expected that there are large differences in Arctic storm characteristics between the reanalysis datasets. Though, some similar Arctic storm characteristics are found between the reanalysis datasets, it is found that the differences in Arctic storm characteristics between the reanalysis datasets are generally higher in winter than in summer. Overall, the results show that there are differences in Arctic storm characteristics between reanalysis datasets, but even larger differences can arise between using 850 hPa relative vorticity or mean sea level pressure as the storm tracking variable, which adds to the uncertainty associated with current Arctic storm characteristics
Language ideological debates about linguistic landscapes: the case of Chinese signage in Richmond, Canada
In 2013, Richmond city council was presented with a petition calling for the regulation of all language signs, drawing national attention to the amount of Chinese-only signage. The signage debate has become well-known in Canada as a result of the
media, which has provided a platform for debate through online reader commentary. By applying concepts from linguistic landscapes, language ideologies and nationalism in addition to analytical tools from SFL, we employ critical discourse studies to examine how representations of and responses to language signage in online news commentary contribute to the construction of in-groups and out-groups in the Canadian context. Findings show that stereotypical representations of ethnicity and culture are represented as a threat to the Canadian status quo. Also, contradictory ideologies of Canadian official bilingualism are employed to justify discrimination against Chinese language speakers. Findings suggest that language ideologies remain deeply tied to understandings of Canadian nationhood and belonging
Identifying the "Right Stuff": An Exploration-Focused Astronaut Job Analysis
Industrial and organizational (I/O) psychologists play a key role in NASA astronaut candidate selection through the identification of the competencies necessary to successfully engage in the astronaut job. A set of psychosocial competencies, developed by I/O psychologists during a prior job analysis conducted in 1996 and updated in 2003, were identified as necessary for individuals working and living in the space shuttle and on the International Space Station (ISS). This set of competencies applied to the space shuttle and applies to current ISS missions, but may not apply to longer-duration or long-distance exploration missions. With the 2015 launch of the first 12- month ISS mission and the shift in the 2020s to missions beyond low earth orbit, the type of missions that astronauts will conduct and the environment in which they do their work will change dramatically, leading to new challenges for these crews. To support future astronaut selection, training, and research, I/O psychologists in NASA's Behavioral Health and Performance (BHP) Operations and Research groups engaged in a joint effort to conduct an updated analysis of the astronaut job for current and future operations. This project will result in the identification of behavioral competencies critical to performing the astronaut job, along with relative weights for each of the identified competencies, through the application of job analysis techniques. While this job analysis is being conducted according to job analysis best practices, the project poses a number of novel challenges. These challenges include the need to identify competencies for multiple mission types simultaneously, to evaluate jobs that have no incumbents as they have never before been conducted, and working with a very limited population of subject matter experts. Given these challenges, under the guidance of job analysis experts, we used the following methods to conduct the job analysis and identify the key competencies for current and potential future missions
Aqueous vanadate removal by iron(II)-bearing phases under anoxic conditions
Copyright © 2020 American Chemical SocietyFunding was provided by the Natural Sciences and Engineering Council of Canada (NSERC) through the Discovery Grants program (Grant No. RGPIN-2014-06589). Additional support awarded to CJV through NSERC – Canada Graduate Scholarship – Masters (NSERC CGS-M) Program. A portion of the research described was performed at the Canadian Light Source, which is supported by the Canada Foundation for Innovation, NSERC, the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council, and the Canadian Institutes of Health Research.Peer ReviewedVanadium contamination is a growing environmental hazard worldwide. Aqueous vanadate (HxVVO4(3−x)− (aq)) concentrations are often controlled by surface complexation with metal (oxyhydr)oxides in oxic environments. However, the geochemical behaviour of this toxic redox sensitive oxyanion in anoxic environments is poorly constrained. Here we describe results of batch experiments to determine kinetics and mechanisms of aqueous H2VVO4− (100 μM) removal under anoxic conditions in suspensions (2.0 g L−1) of magnetite, siderite, pyrite, and mackinawite. We present results of parallel experiments using ferrihydrite (2.0 g L−1) and Fe2+(aq) (200 μM) for comparison. Siderite and mackinawite reached near complete removal (46 µmol g−1) of aqueous vanadate after 3 h and kinetic rates were generally consistent with ferrihydrite. Whereas magnetite removed 18 µmol g−1 of aqueous vanadate after 48 h and uptake by pyrite was limited. Uptake by Fe2+(aq) was observed after 8 h, concomitant with precipitation of secondary Fe phases. X ray absorption spectroscopy revealed V(V) reduction to V(IV) and formation of bidentate corner-sharing surface complexes on magnetite and siderite, and with Fe2+(aq) reaction products. These data also suggest that V(IV) is incorporated into the mackinawite structure. Overall, we demonstrate that Fe(II)-bearing phases can promote aqueous vanadate attenuation and, therefore, limit dissolved V concentrations in anoxic environments
Validation of the Human Ozone Challenge Model as a Tool for Assessing Anti-Inflammatory Drugs in Early Development
This study aimed to test the utility of the ozone challenge model for profiling novel compounds designed to reduce airway inflammation. The authors used a randomized, doubledummy, double-blind, placebo-controlled 3-period crossover design alternating single orally inhaled doses of fluticasone propionate (inhaled corticosteroids, 2mg), oral prednisolone (oral corticosteroids, 50mg), ormatched placebo. At a 2-week interval, 18 healthy ozone responders (>10% increase in sputum neutrophils) underwent a 3-hour ozone (250 ppb)/intermittent exercise challenge starting 1 hour after drug treatment. Airway inflammation was assessed at 2 hours (breath condensate) and 3 hours (induced sputum) after ozone challenge. Compared to placebo, pretreatment with inhaled corticosteroids or oral corticosteroids resulted in a significant reduction (mean [95% confidence interval]) of sputum neutrophils by 62% (35%, 77%) and 64% (39%, 79%) and of sputum supernatant myeloperoxidase by 55% (41%, 66%) and 42% (25%, 56%), respectively. The authors conclude that an optimized ozone challenge model (including ozone responders and ensuring adequate drug levels during exposure) may be useful for testing novel anti-inflammatory compounds in early development
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