QCA as an approach to make sense of micro-level data-centric practices for policy innovation: a walk-through

The paper explores the potentialities and challenges of using a comparative research method — Qualitative Comparative Analysis (QCA) — as a methodological approach for researching policy innovation. The paper argues for QCA to constitute a rigorous and systematic way to explore policy innovation using micro-level experimental and innovative practices in the public sector as the empirical base. Conceptually, we propose considering the importance of policy workers in policy innovation processes. This proposal addresses a gap in policy innovation research that appears to have mostly focused on entrepreneurship while under-appreciating other individual agency explanations of change (e.g., policy workers). Policy innovation researchers should therefore reframe the concept of policy innovation from an out-based view to a process-based view, while avoiding the development of ideographic knowledge. To address this issue, we provide a walk-through of using QCA as a methodological approach to investigate data-centric practices in the public sector. In the walk-through, we simulate the execution of the first three steps of approaching different cases of data-centric practices through QCA, identifying variables and calibrating them. Other researchers might find this approach useful to investigate similar innovative practices in the public sector in the perspective of policy innovation

Spontaneous imbibition in a slit pore: a lattice-gas dynamic mean field study

We present a theoretical study of spontaneous imbibition in a slit pore using a lattice-gas model and a dynamic mean-field theory. Emphasis is put on the influence of the precursor films on the speed of the imbibition front due to liquid mass conservation. This work is dedicated to Bob Evans for his 65th birthday in recognition of his seminal contributions to the theory of fluids in confining geometries.Comment: 17 pages, 13 figure

A novel bacterial l-arginine sensor controlling c-di-GMP levels in Pseudomonas aeruginosa

Nutrients such as amino acids play key roles in shaping the metabolism of microorganisms in natural environments and in host–pathogen interactions. Beyond taking part to cellular metabolism and to protein synthesis, amino acids are also signaling molecules able to influence group behavior in microorganisms, such as biofilm formation. This lifestyle switch involves complex metabolic reprogramming controlled by local variation of the second messenger 3′, 5′-cyclic diguanylic acid (c-di-GMP). The intracellular levels of this dinucleotide are finely tuned by the opposite activity of dedicated diguanylate cyclases (GGDEF signature) and phosphodiesterases (EAL and HD-GYP signatures), which are usually allosterically controlled by a plethora of environmental and metabolic clues. Among the genes putatively involved in controlling c-di-GMP levels in P. aeruginosa, we found that the multidomain transmembrane protein PA0575, bearing the tandem signature GGDEF-EAL, is an l-arginine sensor able to hydrolyse c-di-GMP. Here, we investigate the basis of arginine recognition by integrating bioinformatics, molecular biophysics and microbiology. Although the role of nutrients such as l-arginine in controlling the cellular fate in P. aeruginosa (including biofilm, pathogenicity and virulence) is already well established, we identified the first l-arginine sensor able to link environment sensing, c-di-GMP signaling and biofilm formation in this bacterium

Liouville-type results in exterior domains for radial solutions of fully nonlinear equations

We give necessary and sufficient conditions for the existence of positive radial solutions for a class of fully nonlinear uniformly elliptic equations posed in the complement of a ball in RN, and equipped with homogeneous Dirichlet boundary conditions

Low field magnetotransport in strained Si/SiGe cavities

Low field magnetotransport revealing signatures of ballistic transport effects in strained Si/SiGe cavities is investigated. We fabricated strained Si/SiGe cavities by confining a high mobility Si/SiGe 2DEG in a bended nanowire geometry defined by electron-beam lithography and reactive ion etching. The main features observed in the low temperature magnetoresistance curves are the presence of a zero-field magnetoresistance peak and of an oscillatory structure at low fields. By adopting a simple geometrical model we explain the oscillatory structure in terms of electron magnetic focusing. A detailed examination of the zero-field peak lineshape clearly shows deviations from the predictions of ballistic weak localization theory.Comment: Submitted to Physical Review B, 25 pages, 7 figure

Finite elements for higher order steel–concrete composite beams

none4noThis paper presents finite elements for a higher order steel–concrete composite beam model developed for the analysis of bridge decks. The model accounts for the slab–girder partial interaction, the overall shear deformability, and the shear‐lag phenomenon in steel and concrete components. The theoretical derivation of the solving balance conditions, in both weak and strong form, is firstly addressed. Then, three different finite elements are proposed, which are characterised by (i) linear interpolating functions, (ii) Hermitian polynomial interpolating functions, and (iii) interpolating functions, respectively, derived from the analytical solution expressed by means of exponential matrices. The performance of the finite elements is analysed in terms of the solution con-vergence rate for realistic steel–concrete composite beams with different restraints and loading con-ditions. Finally, the efficiency of the beam model is shown by comparing the results obtained with the proposed finite elements and those achieved with a refined 3D shell finite element model.openGara F.; Carbonari S.; Leoni G.; Dezi L.Gara, F.; Carbonari, S.; Leoni, G.; Dezi, L