Le FORUM, Vol. 37 No. 4

https://digitalcommons.library.umaine.edu/francoamericain_forum/1039/thumbnail.jp

Operationalization of community-based participatory research principles: assessment of the national cancer institute\u27s community network programs

ObjectivesWe examined how National Cancer Institute-funded Community Network Programs (CNPs) operationalized principles of community-based participatory research (CBPR).MethodsWe reviewed the literature and extant CBPR measurement tools. On the basis of that review, we developed a 27-item questionnaire for CNPs to self-assess their operationalization of 9 CBPR principles. Our team comprised representatives of 9 of the National Cancer Institute's 25 CNPs.ResultsOf the 25 CNPs, 22 (88%) completed the questionnaire. Most scored well on CBPR principles of recognizing community as a unit of identity, building on community strengths, facilitating colearning, embracing iterative processes in developing community capacity, and achieving a balance between data generation and intervention. CNPs varied in the extent to which they employed CBPR principles of addressing determinants of health, sharing power among partners, engaging the community in research dissemination, and striving for sustainability.ConclusionsAlthough the development of assessment tools in this field is in its infancy, our findings suggest that fidelity to CBPR processes can be assessed in a variety of settings

Seismic velocity structure of the rifted margin of the eastern Grand Banks of Newfoundland, Canada

We present a compressional seismic velocity profile of the crust of the eastern margin of the Grand Banks of Newfoundland, Canada. This velocity model was obtained by a tomographic inversion of wide-angle data recorded on a linear array of 24 ocean bottom seismometers (OBSs). At the landward side, we imaged a crustal thickness of 27 km in Flemish Pass and beneath Beothuk Knoll, which is thinner than the 35-km-thick crust of the central Grand Banks. We therefore assume that the eastern rim of the Grand Banks stretched uniformly by 25%. Farther seaward, the continental crust tapers rapidly beneath the continental slope to ?6 km thickness. In the distal margin we find a 60-km-wide zone with seismic velocities between 5.0 and 6.5 km s?1 that thins to the southeast from 6 to 2 km, which we interpret as highly extended continental crust. Contrary to other seismic studies of the margins of the Grand Banks, we find seismic velocities of 8 km s?1 and higher beneath this thin crustal layer in the continent-ocean transition. We conclude that mantle was locally emplaced at shallow levels without significant hydration from seawater or serpentinized mantle was removed along a décollement in the final stages of continental rifting. The outer edge of highly extended continental crust borders a 25-km-wide zone where seismic velocities increase gradually from 6.3 km s?1 just below the top of acoustic basement to 7.7 km s?1 at 5 km below basement. We interpret this area as a relatively narrow zone of exhumed and serpentinized continental mantle. Seaward, we imaged a thin and laterally heterogeneous layer with a seismic velocity that increases sharply from 5.0 km s?1 in basement ridges to 7.0 km s?1 at its base, overlying mantle velocities between 7.8 and 8.2 km s?1. We interpret this area as unroofed mantle and very thin oceanic crust that formed at an incipient, magma-starved, ultraslow spreading ridge. A comparison of the conjugate rifted margins of the eastern Grand Banks and the Iberia Abyssal Plain show that they exhibit a similar seaward progression from continental crust to mantle to oceanic crust. This indicates that before continental breakup, rifting exhumed progressively deeper sections of the continental lithosphere on both conjugate margins. A comparison between the continent-ocean transition of the Grand Banks and Flemish Cap shows that the final phase of continental rifting and the formation of the first oceanic crust required more time at the Grand Banks margin than at the southeastern margin of Flemish Cap