Cycloadditions in mixed aqueous solvents: the role of the water concentration

We examined the kinetics of a series of cycloaddition reactions in mixtures of water with methanol, acetonitrile and poly(ethylene glycol) (MW 1000). The reactions include the Diels–Alder (DA) reaction between cyclopentadiene and N-n-butylmaleimide or acridizinium bromide, the retro-Diels-Alder (RDA) reaction of 1,4,4a,9a-tetrahydro-4a-methyl-(1α,4α,4aα,9aα)-1,4-methaneanthracene-9,10-dione and the 1,3-dipolar cycloaddition of benzonitrile oxide with N-n-butylmaleimide. Plots of logk vs the molar concentration or volume fraction of water are approximately linear, but with a characteristic break around 40 M water. This break, absent for the RDA reaction, is ascribed to hydrophobic effects. Comparison with aqueous mixtures of the more hydrophobic 1-propanol shows that these mixtures induce qualitatively similar effects on the rate, but that preferential solvation effects cause the mixtures of 1-propanol to exhibit a more complex behavior of logk on composition. The results are analyzed using the Abraham–Kamlett–Taft model. The solvent effects in aqueous mixtures are not satisfactorily described by this model. For some cycloadditions, small maxima in rate are observed in highly aqueous mixtures of alcohols. The origin of these maxima and the aforementioned breaks is most likely the same.

Transport and Retrieval on ECMO: Setup and Activities of an Immersive Transport and Retrieval on ECMO Workshop

© 2020 The Author(s). This an open access work distributed under the terms of the Creative Commons Attribution Licence (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Extracorporeal Life Support (ECLS) and Extracorporeal Membrane Oxygenation (ECMO) are widely used for acute severe refractory cardiac and/or respiratory failure. An increasing number of patients are treated with ECMO worldwide. This can be attributed to technical and technological advancements, eased access to modern equipment, more regular and accessible training opportunities for practitioners to maintain current skills and develop new ones. Typically, ECMO is provided at tertiary or regional centers which are often university affiliated. In a significant number of patients, ECMO may be initiated at a peripheral hospital before they are transported to a tertiary facility by a specialized multiprofessional ECMO team. The transport phase is however fraught with challenges and untoward events are not uncommon during ECMO transportation, so a robust education and training program is critical to ensure patient safety and optimum outcome. This article describes our experience of developing and running a simulation-based ECMO Transport and Retrieval workshop with multiple immersive scenarios and opportunities for participants to familiarize themselves with the process and the ambulance equipment and environment. Preparation is a key element to successfully run scenarios that are technically challenging to facilitate due to the environment and equipment involved. To date, 136 multidisciplinary ECMO providers have attended the workshop and no incidents have been reported by our teams during actual transfers and retrieval missions with patients on ECMO.Peer reviewe

Ranking Web of Universities: Is Webometrics a Reliable Academic Ranking?

Global university rankings continue to gain growing interest and have high visibility from all stakeholders. Of these, Webometrics Ranking (WR) faces many criticisms about its function. Some people believe WR evaluates only the websites of universities but not their global performance and impact as mentioned by WR authors. This stimulates us to examine the idea of using WR as a reliable academic ranking for the world universities. To test this hypothesis, we apply the WR results with two widely accepted indexes, i.e., the global university rankings and the bibliometrics. Therefore, the WR ranking of the Top 100 institutions are correlated with the corresponding values of six world ranking systems’ 2015 edition (ARWU, USNWR, QS, THE, NTU and URAP) that commonly accepted to evaluate the academic performance of the university, as well as with the objectively bibliometric indicators gathered from the Web of Science (WOS) InCitesTM - Thomson Reuters. The findings revealed that the WR results provide a good correlation with both ranking systems’ results and with 12 bibliometric variables namely: WOS Documents, Times Cited, Citation Impact (CI), Citation Impact: Category Normalized (CNCI), Citation Impact: Journal Normalized (JNCI), Impact Relative to World, % of Top 1% Documents, % of Top 10% Documents, Highly Cited Papers, h-index, International Collaborations, and % Industry Collaborations. The consistency between WR and the studied six rankings increases with increasing the weight percent of the research or bibliometric indicators in these six global rankings. Moreover, the consistency between WR and survey-based rankings (USNWR, THE and QS) increases with decreasing the weight of the subjective reputation survey indicators. The North American, especially USA universities are characterized by the extremely high visibility in WR as well as in the studied seven global rankings. Thus, web-based indicators ranking (WR) offers results of comparable and similar quality to those of the six major global university rankings. Accordingly, they have the capability to rank institutional academic performance. Moreover, the reliability could be enhanced if each university has only one web-domain that accurately reflects its actual performance and activity. We recommend all institutions to apply all ranking systems together since their criteria and indicators complement each other and can form a comprehensive index for covering various HEIs activities/functions worldwide