Vincent Ostrom’s Revolutionary Science of Association [post-print]

Vincent Ostrom challenged epistemic choices at the foundation of modern political science and proposed an alternative conceptualization of democracy based on a theory of federalism he derived from The Federalist and Tocqueville\u27s Democracy in America. This essay examines Vincent Ostrom\u27s critique of contemporary mainstream political theorizing, relates his original theoretical work to the empirical research Elinor Ostrom, other colleagues, and he conducted, advised, or sponsored at The Workshop in Political Theory and Policy Analysis Indiana University, and concludes that Ostrom\u27s democratic alternative constitutes an alternative scientific paradigm as defined by Thomas Kuhn. The paper concludes with a comment on the continuing relevance of Ostrom\u27s critique in the post-9/11 era

Specification and implementation of metadata for secure image provenance information

The booming of AI tools capable of modifying images has equipped fake media producers with strong tools in their arsenal. Complementary to the efforts of implementing fake media detectors, research organizations are designing a standardized way of describing the modification history of digital media in a cryptographically secure way, ensuring that this information cannot be tampered with. This thesis proposes a specification which focuses on JPEG images and specifies a data model based on the JPEG Universal Metadata Box Format (JUMBF) standard. Furthermore, it proposes the encryption of a subset of provenance metadata that could pose privacy-related risks to the users. Along with the specification, a library has been developed to manage provenance information of JPEG images. To that extent, a set of libraries that handle JUMBF information is required to be implemented. These libraries have been submitted as a proposed reference software contributing to the JUMBF standard

O(a^2) corrections to 1-loop matrix elements of 4-fermion operators with improved fermion/gluon actions

We calculate the corrections to the amputated Green's functions of 4-fermion operators, in 1-loop Lattice Perturbation theory. The novel aspect of our calculations is that they are carried out to second order in the lattice spacing, O(a^2). We employ the Wilson/clover action for massless fermions (also applicable for the twisted mass action in the chiral limit) and the Symanzik improved action for gluons. Our calculations have been carried out in a general covariant gauge. Results have been obtained for several popular choices of values for the Symanzik coefficients (Plaquette, Tree-level Symanzik, Iwasaki, TILW and DBW2 action). We pay particular attention to $\Delta F=2$ operators, both Parity Conserving and Parity Violating ($F$ stands for flavour: S, C, B). We study the mixing pattern of these operators, to O(a^2), using the appropriate projectors. Our results for the corresponding renormalization matrices are given as a function of a large number of parameters: coupling constant, clover parameter, number of colors, lattice spacing, external momentum and gauge parameter. The O(a^2) correction terms (along with our previous O(a^2) calculation of $Z_\Psi$) are essential ingredients for minimizing the lattice artifacts which are present in non-perturbative evaluations of renormalization constants with the RI'-MOM method. A longer write-up of this work, including non-perturbative results, is in preparation together with members of the ETM Collaboration.Comment: 8 pages, 1 figure. Presented at the "XXVII International Symposium on Lattice Field Theory", July 26-31 2009, Peking University, Beijing, Chin

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Perturbative renormalization factors and O(a^2) corrections for lattice 4-fermion operators with improved fermion/gluon actions

In this work we calculate the corrections to the amputated Green's functions of 4-fermion operators, in 1-loop Lattice Perturbation theory. One of the novel aspects of our calculations is that they are carried out to O(a^2) (a: lattice spacing). We employ the Wilson/clover action for massless fermions (also applicable for the twisted mass action in the chiral limit) and a family of Symanzik improved actions for gluons. Our calculations have been carried out in a general covariant gauge. Results have been obtained for several popular choices of values for the Symanzik coefficients. While our Green's function calculations regard any pointlike 4-fermion operators which do not mix with lower dimension ones, we pay particular attention to DF=2 operators, both Parity Conserving and Parity Violating (F: flavour). We compute the perturbative renormalization constants for a complete basis of 4-fermion operators and we study their mixing pattern. For some of the actions considered here, even O(a^0) results did not exist in the literature to date. The correction terms which we calculate are essential ingredients for minimizing the lattice artifacts which are present in non-perturbative evaluations of renormalization constants with the RI'-MOM method. Our perturbative results, for the matrix elements of DF=2 operators and for the corresponding renormalization matrices, depend on a large number of parameters: coupling constant, number of colors, lattice spacing, external momentum, clover parameter, Symanzik coefficients, gauge parameter. To make these results most easily accessible, we have included them in the distribution package of this paper, as an ASCII file named: 4-fermi.m; the file is best perused as Mathematica input. The main results of this work have been applied to improve non-perturbative estimates of the B_K-parameter in N_F=2 twisted mass lattice QCD.Comment: 30 pages, 1 figure, 8 table

Mural Folliculitis and Alopecia with Cutaneous Candidiasis in a Beagle Dog

A one-year-old male Beagle dog showed dermatitis, alopecia and scales. Examination of the affected dog revealed generalized alopecia, patchy erythema, and superficial erosions with histological evidence of mural folliculitis. External tests for parasites in scraped skin samples were negative. However, fungal culture tests and polymerase chain reaction revealed the existence of Candida in the lesion. These results suggest that cutaneous candidiasis may induce mural folliculitis and alopecia in dogs