The objectives of the US Exploring Expedition's circumnavigation (1838-1842): longitude, nautical charting and the establishment of modern geographic coordinates

This article analyzes the main objectives of the scientific voyage to circumnavigate the earth, undertaken by the United States from 1838 to 1842. Charting was one of the most important of the scientific and strategic goals of the exploratory voyage. The initiative for the undertaking was the search for exact positioning on the high seas after the establishment of the longitude system, when nautical charts and maps from various countries were compared, and other, new ones were drawn. The United States participated in this international effort, leading to the creation of its own cartographic system.

SENSITIVE METHOD FOR DETERMINATION OF PIPLARTINE, AN ALKALOID AMIDE FROM Piper SPECIES, IN RAT PLASMA SAMPLES BY LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY

Piplartine (PPTN) is an alkaloid amide found in Piper species that presents different activities. PPTN determination in rat plasma is necessary to better understand its biological effects. The aim of this study was to develop a sensitive LC-MS/MS method for the determination of PPTN in rat plasma. The performance criteria for linearity, sensitivity, precision, accuracy, recovery, and stability have been assessed and were within the recommended guidelines. The validated method proved to be suitable in a pilot study of PPTN kinetic disposition in rat plasma after a single intraperitoneal dose, and represents an appropriate tool to further pharmacokinetic studies.

Sensitive method for determination of piplartine, an alkaloid amide from Piper species, in rat plasma samples by liquid chromatography-tandem mass spectrometry

Piplartine (PPTN) is an alkaloid amide found in Piper species that presents different activities. PPTN determination in rat plasma is necessary to better understand its biological effects. The aim of this study was to develop a sensitive LC-MS/MS method for the determination of PPTN in rat plasma. The performance criteria for linearity, sensitivity, precision, accuracy, recovery, and stability have been assessed and were within the recommended guidelines. The validated method proved to be suitable in a pilot study of PPTN kinetic disposition in rat plasma after a single intraperitoneal dose, and represents an appropriate tool to further pharmacokinetic studies.

Os objetivos da circunavegação da U.S. Exploring Expedition (1838-1842): longitude, mapeamento náutico e instituição das coordenadas geográficas modernas

Analisa o principal objetivo da viagem científica de circunavegação realizada pelos EUA entre 1838 e 1842. A tarefa de mapeamento destaca-se entre outras metas científico-estratégicas da viagem exploratória. A iniciativa da empreitada foi movida pela busca da exata localização em alto-mar após a instituição do sistema de longitudes, quando cartas náuticas e mapas de vários países foram conferidos, e outros, novos, desenhados. Os EUA participaram desse esforço internacional, dando início à constituição de um sistema cartográfico próprio.