Special Issue: landscape urbanism and green infrastructure

With the notion of landscape urbanism long neglected, interlinkages between ecology and architecture in the built environment are becoming visible. Yet, the diversity in understandings of the interconnections between cities and nature is the starting point for our research interest. This volume contains nine thoroughly refereed contributions concerning a wide range of topics in landscape architecture and urban green infrastructure. While some papers attempt to conceptualize the relation further, others clearly have an empirical focus. Thereby, this special issue provides a rich body of work, and will act as a starting point for further studies on biophilic urbanism and integrative policies, such as the sustainable development goals of the United Nations.Agência financiadora FCT-Foundation for Science and Technology PTDC/GES-URB/31928/2017info:eu-repo/semantics/publishedVersio

When Does Patent Protection Stimulate Innovation?

Patents act as an incentive to innovate. However, as this paper argues, patents can lead the patent holder to rest on his laurels and at the same time discourage some innovators from innovating, reducing knowledge spillovers. The combined result of the above suggests an inverse U relationship between patent protection and output growth.Intellectual property, patent races, growth.

Two-loop renormalization of vector, axial-vector and tensor fermion bilinears on the lattice

We compute the two-loop renormalization functions, in the RI' scheme, of local bilinear quark operators $\bar{\psi}\Gamma\psi$, where $\Gamma$ corresponds to the Vector, Axial-Vector and Tensor Dirac operators, in the lattice formulation of QCD. We consider both the flavor nonsinglet and singlet operators. We use the clover action for fermions and the Wilson action for gluons. Our results are given as a polynomial in $c_{SW}$, in terms of both the renormalized and bare coupling constant, in the renormalized Feynman gauge. Finally, we present our results in the MSbar scheme, for easier comparison with calculations in the continuum. The corresponding results, for fermions in an arbitrary representation, together with some special features of superficially divergent integrals, are included in the Appendices.Comment: 42 pages, 10 figures. Version accepted in PRD. Added comments and references, provided per diagram numerical values; final results and conclusions left unchanged. This paper is a sequel to arXiv:0707.2906 (Phys. Rev. D76 (2007) 094514), which regards the scalar and pseudoscalar cases

Resummation of Cactus Diagrams in Lattice QCD, to all Orders

We show how to perform a resummation, to all orders in perturbation theory, of a certain class of gauge invariant tadpole-like diagrams in Lattice QCD. These diagrams are often largely responsible for lattice artifacts. Our resummation leads to an improved perturbative expansion. Applied to a number of cases of interest, e.g. the lattice renormalization of some two-fermion operators, this expansion yields results remarkably close to corresponding nonperturbative estimates. We consider in our study both the Wilson and the clover action for fermions.Comment: LATTICE99(Improvement and Renormalization), 3 pages, LATeX with eps figures, uses espcrc2.sty. Corrected a statement regarding comparison with other methods. (We thank A. Kronfeld for bringing this point to our attention.