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    Extending tensors on polar manifolds

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    Let MM be a Riemannian manifold with a polar action by the Lie group GG, with section Σ⊂M\Sigma\subset M and generalized Weyl group WW. We show that restriction to Σ\Sigma is a surjective map from the set of smooth GG-invariant tensors on MM onto the set of smooth WW-invariant tensors on Σ\Sigma. Moreover, we show that every smooth WW-invariant Riemannian metric on Σ\Sigma can be extended to a smooth GG-invariant Riemannian metric on MM with respect to which the GG-action remains polar with the same section Σ\Sigma.Comment: arXiv admin note: text overlap with arXiv:1205.476

    Pairing correlations with single Cooper pair transfer to individual quantal states

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    With the help of the static and dynamic mean field spectroscopic amplitudes, taking into account successive and simultaneous transfer channels properly corrected because of non-orthogonality effects, as well as describing the associated elastic channels in terms of experimentally determined optical potentials, one obtains absolute, two-particle transfer differential cross sections which provide an overall account of the data within experimental errors. One of the first results connected with such quantitative studies of pairing correlations in nuclei is the observation of phonon mediated pairing in the exotic halo nucleus 11^{11}Li, and the associated discovery of a new mechanism to break nuclear gauge symmetry: bootstrap, pigmy-resonance-mediated Cooper pair binding.Comment: Contributed chapter in "50 Years of Nuclear BCS", edited by R. A. Broglia and V. Zelevinsk

    Are small Sub-Sahara African farmers willing to pay for vegetative propagated orange fleshed sweetpotato planting material? Evidence from Central Mozambique

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    This paper evaluates farmers’ willingness to pay (WTP) for the vegetative propagated orange fleshed sweetpotato (OFSP) planting material that is many times considered as a public good. Famers’ WTP for OFSP vines was elicited by conducting a real choice experiment (RCE) among 121 small sweetpotato growers in central Mozambique with prior experience growing OFSP but with no participation in OFSP vine distributions in the previous 3 years of the experiment. Results reveals a higher farmers’ willingness to pay for OFSP varieties (US0.07−0.12)comparedtothenon−orangeplantingmaterial(US0.07-0.12) compared to the non-orange planting material (US 0.03) and compared to the traditional subsidized price of clean sweetpotato vines (US$ 0.06) used in Mozambique. These results may encourage formation of a network of private vine multipliers that would supply permanently OFSP planting material in wider areas.Agricultural and Food Policy, Community/Rural/Urban Development, Consumer/Household Economics, Farm Management, Food Security and Poverty, Health Economics and Policy, International Development, Production Economics, Q16,
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