723 research outputs found
A statistical survey of dayside pulsed ionospheric flows as seen by the CUTLASS Finland HF radar
International audienceNearly two years of 2-min resolution data and 7- to 21-s resolution data from the CUTLASS Finland HF radar have undergone Fourier analysis in order to study statistically the occurrence rates and repetition frequencies of pulsed ionospheric flows in the noon-sector high-latitude ionosphere. Pulsed ionospheric flow bursts are believed to be the ionospheric footprint of newly reconnected geomagnetic field lines, which occur during episodes of magnetic flux transfer to the terrestrial magnetosphere - flux transfer events or FTEs. The distribution of pulsed ionospheric flows were found to be well grouped in the radar field of view, and to be in the vicinity of the radar signature of the cusp footprint. Two thirds of the pulsed ionospheric flow intervals included in the statistical study occurred when the interplanetary magnetic field had a southward component, supporting the hypothesis that pulsed ionospheric flows are a reconnection-related phenomenon. The occurrence rate of the pulsed ionospheric flow fluctuation period was independent of the radar scan mode. The statistical results obtained from the radar data are compared to occurrence rates and repetition frequencies of FTEs derived from spacecraft data near the magnetopause reconnection region, and to ground-based optical measurements of poleward moving auroral forms. The distributions obtained by the various instruments in different regions of the magnetosphere were remarkably similar. The radar, therefore, appears to give an unbiased sample of magnetopause activity in its routine observations of the cusp footprint
A statistical survey of dayside pulsed ionospheric flows as seen by the CUTLASS Finland HF radar
Statistical observations of the MLT, latitude and size of pulsed ionospheric flows with the CUTLASS Finland radar
A comparison of field-line resonances observed at the Goose Bay and Wick radars
Le socialisme européen est secoué, dans les années 1890-1893, par l’éclosion d’une aile gauche de sensibilité antiparlementaire – SDB aux Pays-Bas, Jungen en Allemagne, POSR en France. Une fraction du mouvement anarchiste va s’y intéresser et tenter une alliance voire une recomposition avec ce courant socialiste, qui permettrait de contester l’hégémonie de la social-démocratie. Du congrès de Zurich (1893) à celui de Paris (1900), un groupe de militants – Pouget, Pelloutier, Lazare, Hamon – va être au cœur de ce processus. La tentative va échouer, mais est révélatrice d’une volonté de l’anarchisme français de « retour au socialisme » à cette époque, et constitue un prélude méconnu à sa période syndicaliste
Drawbacks and benefits associated with inter-organizational collaboration along the discovery-development-delivery continuum: a cancer research network case study
BACKGROUND: The scientific process around cancer research begins with scientific discovery, followed by development of interventions, and finally delivery of needed interventions to people with cancer. Numerous studies have identified substantial gaps between discovery and delivery in health research. Team science has been identified as a possible solution for closing the discovery to delivery gap; however, little is known about effective ways of collaborating within teams and across organizations. The purpose of this study was to determine benefits and drawbacks associated with organizational collaboration across the discovery-development-delivery research continuum. METHODS: Representatives of organizations working on cancer research across a state answered a survey about how they collaborated with other cancer research organizations in the state and what benefits and drawbacks they experienced while collaborating. We used exponential random graph modeling to determine the association between these benefits and drawbacks and the presence of a collaboration tie between any two network members. RESULTS: Different drawbacks and benefits were associated with discovery, development, and delivery collaborations. The only consistent association across all three was with the drawback of difficulty due to geographic differences, which was negatively associated with collaboration, indicating that those organizations that had collaborated were less likely to perceive a barrier related to geography. The benefit, enhanced access to other knowledge, was positive and significant in the development and delivery networks, indicating that collaborating organizations viewed improved knowledge exchange as a benefit of collaboration. ‘Acquisition of additional funding or other resources’ and ‘development of new tools and methods’ were negatively significantly related to collaboration in these networks. So, although improved knowledge access was an outcome of collaboration, more tangible outcomes were not being realized. In the development network, those who collaborated were less likely to see ‘enhanced influence on treatment and policy’ and ‘greater quality or frequency of publications’ as benefits of collaboration. CONCLUSION: With the exception of the positive association between knowledge transfer and collaboration and the negative association between geography and collaboration, the significant relationships identified in this study all reflected challenges associated with inter-organizational collaboration. Understanding network structures and the perceived drawbacks and benefits associated with collaboration will allow researchers to build and funders to support successful collaborative teams and perhaps aid in closing the discovery to delivery gap
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