381 research outputs found

    Soft supersymmetry breaking in the nonlinear sigma model

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    In this work we discuss the dynamical generation of mass in a deformed N=1{\cal N}=1 supersymmetric nonlinear sigma model in a two-dimensional (D=1+1D=1+1) space-time. We introduce the deformation by imposing a constraint that softly breaks supersymmetry. Through the tadpole method, we compute the effective potential at leading order in 1/N1/N expansion showing that the model exhibit a dynamical generation of mass to the matter fields. Supersymmetry is recovered in the limit of the deformation parameter going to zero.Comment: 9 pages, 2 figures. Revised version. arXiv admin note: text overlap with arXiv:1308.471

    Place-based innovation ecosystems : Boston-Cambridge innovation districts

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    This report focuses on the case study of the Boston area and identifies the key success factors in the Boston regional innovation ecosystem. It discusses how the macro-innovation eco-ecosystem is composed by a variety of interconnected micro-innovation ecosystems, mutually reinforcing each other and making the entire “territorial” system successful. The spatial configuration of these micro-innovation ecosystems at the urban scale has been specifically investigated, thus leading the authors to theorize that the Innovation District may act as an enabler for place-based innovation. Evidence from the Boston case study shows that there is not a single magic recipe for the successful implementation of place-based and social innovation-driven strategies. On the contrary, the variety of place-grounded combinations of micro and macro initiatives, embedded in the social and spatial fine grain of places and encompassing a diversity of actors, can create the conditions that enable places to thrive and local economic activities to grow in a sustainable way

    Rendimento de grãos de trigo e tricale com utilização de torta de mamona.

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    bitstream/item/36425/1/boletim-128.pd

    Curva de embebição de sementes de repolho submetidas a envelhecimento artificial.

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    bitstream/item/141964/1/Boletim-215.pd
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