3 resultados para origin of the Second World War
em Universidad de Alicante
Resumo:
The synthesis of a GSK 2nd generation inhibitor of the hepatitis C virus, by enantioselective 1,3-dipolar cycloaddition between a leucine derived iminoester and tert-butyl acrylate, was studied. The comparison between silver(I) and gold(I) catalysts in this reaction was established by working with chiral phosphoramidites or with chiral BINAP. The best reaction conditions were used for the total synthesis of the hepatitis C virus inhibitor by a four step procedure affording this product in 99% ee and in 63% overall yield. The origin of the enantioselectivity of the chiral gold(I) catalyst was justified according to DFT calculations, the stabilizing coulombic interaction between the nitrogen atom of the thiazole moiety and one of the gold atoms being crucial.
Resumo:
The synthesis of nitrogenated carbon nanotubes (N-CNTs) with up to 6.1 wt% N, via the use of pyridine as the nitrogen containing carbon precursor, can provide a facile route to significantly enhance the low intrinsic specific capacitance of carbon nanotubes. The nitrogen functionalities determine this, at least, five-fold increase of the specific capacitance.
Resumo:
This historical study uses qualitative methods to analyze and describe the components of the material world of nursing care in Spain between 1855 and 1955 based on the analysis of eight nurse training manuals. A total of 360 objects and 45 procedures were recorded. Manual analysis was carried out concurrently with data collection based on the Grounded Theory approach. Findings show that the material world of health care was composed of objects that were handed down by the medical profession to health care professionals and adapted objects, improvised mainly out of everyday household items. While the handing down of medical tools and instruments could be said to be a theoretical and technical achievement, it is not clear whether it was also a scientific accomplishment. The improvisation of objects out of everyday household items promoted by the manuals highlights the artisan-like and ingenious nature of nursing practice, which should be explored further in future studies to provide a greater understanding and promote the recognition of these objects as a health care technology.