384 research outputs found

    Soft supersymmetry breaking in the nonlinear sigma model

    Full text link
    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

    Get PDF
    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.

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

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

    Get PDF
    bitstream/item/141964/1/Boletim-215.pd
    corecore