65 research outputs found
Eclipses of the inner satellites of Jupiter observed in 2015
During the 2014-2015 campaign of mutual events, we recorded ground-based
photometric observations of eclipses of Amalthea (JV) and, for the first time,
Thebe (JXIV) by the Galilean moons. We focused on estimating whether the
positioning accuracy of the inner satellites determined with photometry is
sufficient for dynamical studies. We observed two eclipses of Amalthea and one
of Thebe with the 1 m telescope at Pic du Midi Observatory using an IR filter
and a mask placed over the planetary image to avoid blooming features. A third
observation of Amalthea was taken at Saint-Sulpice Observatory with a 60 cm
telescope using a methane filter (890 nm) and a deep absorption band to
decrease the contrast between the planet and the satellites. After background
removal, we computed a differential aperture photometry to obtain the light
flux, and followed with an astrometric reduction. We provide astrometric
results with an external precision of 53 mas for the eclipse of Thebe, and 20
mas for that of Amalthea. These observation accuracies largely override
standard astrometric measurements. The (O-C)s for the eclipse of Thebe are 75
mas on the X-axis and 120 mas on the Y-axis. The (O-C)s for the total eclipses
of Amalthea are 95 mas and 22 mas, along the orbit, for two of the three
events. Taking into account the ratio of (O-C) to precision of the astrometric
results, we show a significant discrepancy with the theory established by
Avdyushev and Ban'shikova in 2008, and the JPL JUP 310 ephemeris.Comment: 7 pages, 10 figures, 4 table
Digital Scrapbook – can we enable interlinked and recursive knowledge equilibrium?
We investigate possible tools and approaches to develop a Digital Scrapbook, a virtual research environment inspired by the recursive nature of research for scholars where they can combine web and own resources into a new scholarly edition readily enabled for Open Access. Web resources are interlinked in the digital scrapbook by content capture and detail selection, rather than sole bookmark or link to resource URL, along with necessary accompanying metadata. We analyse several open source and commercial tools, with special focus on a Scrapbook-X Firefox Add-On, in order to match to desired Digital Scrapbook features. We further address the wider requirement context for development of such Digital Scrapbook environment, discussing both technical and user experience dimensions. We conclude with a recommendation on how to approach the development and operation of a Digital Scrapbook environment
Digitale Bildarchive für Kultur und Wissenschaft
Die Forderung der Deutschen Forschungsgemeinschaft und der Allianz der deutschen Wissenschaftsorganisationen nach öffentlichem und nachhaltigem Zugang zu wissenschaftlichen Daten in Verbindung mit nicht-kommerzieller Technologie zeigt auf, dass die Präsentation von digitalen Inhalten und die Langzeitarchivierung eine immer wichtigere Rolle einnimmt. Fasst man den Blick weiter und betrachtet Wissenschaft und Kultur allgemein, so droht, durch die hohe Flüchtigkeit der digital gespeicherten Informationen, dass bedeutsame Daten auf Dauer verloren gehen. Daher ist die Sicherstellung der zukünftigen Lesbarkeit und Interpretierbarkeit der digitalen Daten von entscheidender Bedeutung. Zur digitalen Langzeitarchivierung bzw. Langzeitverfügbarmachung werden Strategien benötigt, die die Erhaltung der dauerhaften Verfügbarkeit und damit eine Nachnutzung und Interpretierbarkeit der digital gespeicherten Informationen ermöglichen. Dies kann nur durch Auswahl eines geeigneten Archivsystems, bestimmter Dateiformate und Einsetzung weit verbreiteter Metadaten-Standards erreicht werden. Ein solches System, das kollaboratives Arbeiten und Langzeitarchivierung gleichermaßen ermöglicht, ist das Bildverwaltungssystem “Imeji”. Der folgende Text führt einzelne Merkmale von Imeji aus und stellt zwei Fallbeispiele der Anwendung vor
Antikinetoplastid SAR study in 3-nitroimidazopyridine series: identification of a novel non-genotoxic and potent anti-T. b. brucei hit-compound with improved pharmacokinetic properties
To study the antikinetoplastid 3-nitroimidazo[1,2-a]pyridine pharmacophore, a structure-activity relationship study was conducted through the synthesis of 26 original derivatives and their in vitro evaluation on both Leishmania spp and Trypanosoma brucei brucei. This SAR study showed that the antitrypanosomal pharmacophore was less restrictive than the antileishmanial one and highlighted positions 2, 6 and 8 of the imidazopyridine ring as key modulation points. None of the synthesized compounds allowed improvement in antileishmanial activity, compared to previous hit molecules in the series. Nevertheless, compound 8, the best antitrypanosomal molecule in this series (EC50 = 17 nM, SI = 2650 & E° = -0.6 V), was not only more active than all reference drugs and previous hit molecules in the series but also displayed improved aqueous solubility and better in vitro pharmacokinetic characteristics: good microsomal stability (T1/2 > 40 min), moderate albumin binding (77%) and moderate permeability across the blood brain barrier according to a PAMPA assay. Moreover, both micronucleus and comet assays showed that nitroaromatic molecule 8 was not genotoxic in vitro. It was evidenced that bioactivation of molecule 8 was operated by T. b. brucei type 1 nitroreductase, in the same manner as fexinidazole. Finally, a mouse pharmacokinetic study showed that 8 displayed good systemic exposure after both single and repeated oral administrations at 100 mg/kg (NOAEL) and satisfying plasmatic half-life (T1/2 = 7.7 h). Thus, molecule 8 appears as a good candidate for initiating a hit to lead drug discovery program
ETHANOL AND NITRIC OXIDE IN QUALITY MAINTENANCE OF ‘GALAXY’ APPLES STORED UNDER CONTROLLED ATMOSPHERE
Território e territorialidade no contexto hospitalar: uma abordagem interdisciplinar
Este artigo trata o hospital como território de organização complexa, atravessado por múltiplos interesses, que ocupa lugar crítico na prestação de serviços de saúde, lugar de construção de identidades profissionais, com grande reconhecimento social. O objetivo diz respeito a compreender o hospital na perspectiva interdisciplinar. Para tanto, buscou-se o referencial teórico referente às concepções de território e territorialidade, oriundas da geografia e de outros campos do conhecimento, como a ciência da saúde e a filosofia. A partir da interação entre estas disciplinas aborda-se o hospital como território de produção de atos de saúde formado por segmentos e superfícies, agenciamentos entre profissionais e usuários que se entrecortam em um emaranhado de linhas de segmentaridade; nós, redes e malhas que revelam a produção territorial; poder e disciplinamento e o saber-poder que revelam as relações sociais, efetivadas entre os sujeitos e o objeto, ou seja, as relações que se concretizam no território e significam territorialidade. Concluiu-se, então, que o território hospitalar, como os demais territórios, é a expressão concreta e abstrata do espaço apropriado, produzido, formado em sua multidimensionalidade, pelos atores sociais que o (re)definem constantemente em suas cotidianidades, num campo de forças relacionalmente emaranhado por poderes nas mais variadas intensidades
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